 
# Contents

  1.  Preface
  2.  Chapter 1: The Building Site
    1.  1.02 Building in Context
    2.  1.03 Sustainability
    3.  1.04 Green Building
    4.  1.05 Leed® Green Building Rating System
    5.  1.06 The 2030 Challenge
    6.  1.07 Site Analysis
    7.  1.08 Soils
    8.  1.09 Soil Mechanics
    9.  1.10 Topography
    10.  1.11 Topography
    11.  1.12 Plant Materials
    12.  1.13 Trees
    13.  1.14 Solar Radiation
    14.  1.15 Solar Radiation
    15.  1.16 Passive Solar Design
    16.  1.17 Passive Solar Design
    17.  1.18 Solar Shading
    18.  1.19 Daylighting
    19.  1.20 Precipitation
    20.  1.21 Site Drainage
    21.  1.22 Wind
    22.  1.23 Sound & Views
    23.  1.24 Regulatory Factors
    24.  1.25 Zoning Ordinances
    25.  1.26 Site Access & Circulation
    26.  1.27 Pedestrian Circulation
    27.  1.28 Vehicular Circulation
    28.  1.29 Vehicular Parking
    29.  1.30 Slope Protection
    30.  1.31 Retaining Walls
    31.  1.32 Retaining Walls
    32.  1.33 Retaining Walls
    33.  1.34 Paving
    34.  1.35 Paving
    35.  1.36 The Site Plan
    36.  1.37 The Site Plan
    37.  1.38 Site Description
  3.  Chapter 2: The Building
    1.  2.02 The Building
    2.  2.03 Building Systems
    3.  2.04 Building Systems
    4.  2.05 Building Codes
    5.  2.06 Types Of Construction
    6.  2.07 Occupancy Classification
    7.  2.08 Loads on Buildings
    8.  2.09 Wind Loads
    9.  2.10 Earthquake Loads
    10.  2.11 Structural Forces
    11.  2.12 Structural Equilibrium
    12.  2.13 Columns
    13.  2.14 Beams
    14.  2.15 Beam Spans
    15.  2.16 Trusses
    16.  2.17 Frames & Walls
    17.  2.18 Plate Structures
    18.  2.19 Structural Units
    19.  2.20 Structural Spans
    20.  2.21 Structural Patterns
    21.  2.22 Lateral Stability
    22.  2.23 Lateral Stability
    23.  2.24 High-Rise Structures
    24.  2.25 Arches & Vaults
    25.  2.26 Domes
    26.  2.27 Shell Structures
    27.  2.28 Cable Structures
    28.  2.29 Membrane Structures
    29.  2.30 Joints & Connections
  4.  Chapter 3: Foundation Systems
    1.  3.02 Foundation Systems
    2.  3.03 Foundation Systems
    3.  3.04 Types of Foundation Systems
    4.  3.05 Types of Foundation Systems
    5.  3.06 Underpinning
    6.  3.07 Excavation Support Systems
    7.  3.08 Shallow Foundations
    8.  3.09 Spread Footings
    9.  3.10 Foundation Walls
    10.  3.11 Foundation Walls
    11.  3.12 Foundation Walls
    12.  3.13 Foundation Walls
    13.  3.14 Foundation Walls
    14.  3.15 Foundation Walls
    15.  3.16 Column Footings
    16.  3.17 Foundations on Sloping Ground
    17.  3.18 Concrete Slabs on Grade
    18.  3.19 Concrete Slabs on Grade
    19.  3.20 Concrete Slabs on Grade
    20.  3.21 Concrete Slabs on Grade
    21.  3.22 Pole Foundations
    22.  3.23 Pole Foundations
    23.  3.24 Deep Foundations
    24.  3.25 Pile Foundations
    25.  3.26 Caisson Foundations
  5.  Chapter 4: Floor Systems
    1.  4.02 Floor Systems
    2.  4.03 Floor Systems
    3.  4.04 Concrete Beams
    4.  4.05 Concrete Slabs
    5.  4.06 Concrete Slabs
    6.  4.07 Concrete Slabs
    7.  4.08 Prestressed Concrete
    8.  4.09 Prestressed Concrete
    9.  4.10 Concrete Formwork & Shoring
    10.  4.11 Precast Concrete Floor Systems
    11.  4.12 Precast Concrete Units
    12.  4.13 Precast Concrete Connections
    13.  4.14 Structural Steel Framing
    14.  4.15 Structural Steel Framing
    15.  4.16 Steel Beams
    16.  4.17 Steel Beam Connections
    17.  4.18 Steel Beam Connections
    18.  4.19 Open-Web Steel Joists
    19.  4.20 Open-Web Joist Framing
    20.  4.21 Open-Web Joist Framing
    21.  4.22 Metal Decking
    22.  4.23 Light-Gauge Steel Joists
    23.  4.24 Light-Gauge Joist Framing
    24.  4.25 Light-Gauge Joist Framing
    25.  4.26 Wood Joists
    26.  4.27 Wood Joists
    27.  4.28 Wood Joist Framing
    28.  4.29 Wood Joist Framing
    29.  4.30 Wood Joist Framing
    30.  4.31 Wood Joist Framing
    31.  4.32 Wood Subflooring
    32.  4.33 Prefabricated Joists & Trusses
    33.  4.34 Prefabricated Joists & Trusses
    34.  4.35 Wood Beams
    35.  4.36 Wood Beam Supports
    36.  4.37 Wood Post-Beam Connections
    37.  4.38 Wood Plank-and-Beam Framing
    38.  4.39 Wood Plank-and-Beam Framing
    39.  4.40 Wood Decking
  6.  Chapter 5: Wall Systems
    1.  5.02 Wall Systems
    2.  5.03 Wall Systems
    3.  5.04 Concrete Columns
    4.  5.05 Concrete Columns
    5.  5.06 Concrete Walls
    6.  5.07 Concrete Formwork
    7.  5.08 Concrete Formwork
    8.  5.09 Concrete Surfacing
    9.  5.10 Precast Concrete Walls
    10.  5.11 Precast Concrete Wall Panels & Columns
    11.  5.12 Precast Concrete Connections
    12.  5.13 Tilt-Up Construction
    13.  5.14 Masonry Walls
    14.  5.15 Masonry Walls
    15.  5.16 Unreinforced Masonry Walls
    16.  5.17 Unreinforced Masonry Walls
    17.  5.18 Reinforced Masonry Walls
    18.  5.19 Masonry Columns & Pilasters
    19.  5.20 Masonry Arches
    20.  5.21 Masonry Lintels
    21.  5.22 Expansion & Control Joints
    22.  5.23 Masonry Wall Sections
    23.  5.24 Masonry Wall Sections
    24.  5.25 Masonry Wall Sections
    25.  5.26 Masonry Bonding
    26.  5.27 Masonry Bonding
    27.  5.28 Structural Clay Tile
    28.  5.29 Glass Block
    29.  5.30 Glass Block
    30.  5.31 Adobe Construction
    31.  5.32 Rammed-Earth Construction
    32.  5.33 Stone Masonry
    33.  5.34 Stone Masonry
    34.  5.35 Structural Steel Framing
    35.  5.36 Structural Steel Framing
    36.  5.37 Steel Columns
    37.  5.38 Steel Columns
    38.  5.39 Light-Gauge Steel Studs
    39.  5.40 Light-Gauge Stud Framing
    40.  5.41 Balloon Framing
    41.  5.42 Platform Framing
    42.  5.43 Wood Stud Framing
    43.  5.44 Wood Stud Framing
    44.  5.45 Wood Stud Framing
    45.  5.46 Stud Wall Sheathing
    46.  5.47 Wood Columns
    47.  5.48 Wood Post-and-Beam Framing
    48.  5.49 Wood Post-Beam Connections
    49.  5.50 Wood Post-Beam Connections
  7.  Chapter 6: Roof Systems
    1.  6.02 Roof Systems
    2.  6.03 Roof Slopes
    3.  6.04 Reinforced Concrete Roof Slabs
    4.  6.05 Precast Concrete Roof Systems
    5.  6.06 Structural Steel Roof Framing
    6.  6.07 Steel Rigid Frames
    7.  6.08 Steel Trusses
    8.  6.09 Truss Types
    9.  6.10 Space Frames
    10.  6.11 Space Frames
    11.  6.12 Open-Web Steel Joists
    12.  6.13 Open-Web Joist Framing
    13.  6.14 Metal Roof Decking
    14.  6.15 Cementitious Roof Planks
    15.  6.16 Rafter Framing
    16.  6.17 Rafter Framing
    17.  6.18 Light-Gauge Roof Framing
    18.  6.19 Wood Rafters
    19.  6.20 Wood Rafter Framing
    20.  6.21 Wood Rafter Framing
    21.  6.22 Wood Rafter Framing
    22.  6.23 Roof Sheathing
    23.  6.24 Wood Plank-and-Beam Framing
    24.  6.25 Wood Plank-and-Beam Framing
    25.  6.26 Wood Post-Beam Connections
    26.  6.27 Wood Post-Beam Connections
    27.  6.28 Wood Trusses
    28.  6.29 Wood Trusses
    29.  6.30 Wood Trussed Rafters
  8.  Chapter 7: Moisture & Thermal Protection
    1.  7.02 Moisture & Thermal Protection
    2.  7.03 Underlayment for Shingle Roofing
    3.  7.04 Wood Shingles
    4.  7.05 Wood Shakes
    5.  7.06 Composition Shingles
    6.  7.07 Slate Shingles
    7.  7.08 Tile Roofing
    8.  7.09 Vegetated Roofing
    9.  7.10 Corrugated Metal Roofing
    10.  7.11 Sheet Metal Roofing
    11.  7.12 Flat Roof Assemblies
    12.  7.13 Flat Roof Assemblies
    13.  7.14 Built-Up Roofing Systems
    14.  7.15 Single-Ply Roofing Systems
    15.  7.16 Single-Ply Roofing Systems
    16.  7.17 Roof Drainage
    17.  7.18 Flashing
    18.  7.19 Roof Flashing
    19.  7.20 Roof Flashing
    20.  7.21 Flashing Roof Penetrations
    21.  7.22 Wall Flashing
    22.  7.23 Rainscreen Wall Systems
    23.  7.24 Curtain Walls
    24.  7.25 Curtain Walls
    25.  7.26 Curtain Walls
    26.  7.27 Precast Concrete Panels
    27.  7.28 Masonry Veneer
    28.  7.29 Masonry Veneer
    29.  7.30 Stone Veneer
    30.  7.31 Metal Cladding
    31.  7.32 Plywood Siding
    32.  7.33 Wood Shingle Siding
    33.  7.34 Horizontal Board Siding
    34.  7.35 Vertical Board Siding
    35.  7.36 Stucco
    36.  7.37 Stucco Details
    37.  7.38 Exterior Insulation & Finish Systems
    38.  7.39 Thermal Insulation
    39.  7.40 Thermal Resistance of Building Materials
    40.  7.41 Insulating Materials
    41.  7.42 Insulating Materials
    42.  7.43 Insulating Roofs & Floors
    43.  7.44 Insulating Walls
    44.  7.45 Moisture Control
    45.  7.46 Vapor Retarders
    46.  7.47 Ventilation
    47.  7.48 Movement Joints
    48.  7.49 Movement Joints
    49.  7.50 Joint Sealants
  9.  Chapter 8: Doors & Windows
    1.  8.02 Doors & Windows
    2.  8.03 Doors & Doorways
    3.  8.04 Door Operation
    4.  8.05 Hollow Metal Doors
    5.  8.06 Hollow Metal Doorframes
    6.  8.07 Hollow Metal Doorframes
    7.  8.08 Wood Flush Doors
    8.  8.09 Wood Rail & Stile Doors
    9.  8.10 Wood Doorframes
    10.  8.11 Sliding Glass Doors
    11.  8.12 Folding & Pocket Sliding Doors
    12.  8.13 Overhead & Coiling Doors
    13.  8.14 Glass Entrance Doors
    14.  8.15 Storefronts
    15.  8.16 Revolving Doors
    16.  8.17 Door Hardware
    17.  8.18 Door Hinges
    18.  8.19 Door Locksets
    19.  8.20 Panic Hardware & Closers
    20.  8.21 Weatherstripping & Thresholds
    21.  8.22 Window Elements
    22.  8.23 Window Operation
    23.  8.24 Metal Windows
    24.  8.25 Metal Windows
    25.  8.26 Wood Windows
    26.  8.27 Wood Windows
    27.  8.28 Glazing Systems
    28.  8.29 Glazing Systems
    29.  8.30 Insulating Glass
    30.  8.31 Glazed Curtain Walls
    31.  8.32 Glazed Curtain Walls
    32.  8.33 Glazed Curtain Walls
    33.  8.34 Glazed Curtain Walls
    34.  8.35 Double-Skin Facades
    35.  8.36 Skylights
    36.  8.37 Skylight Details
    37.  8.38 Sunspaces
  10.  Chapter 9: Special Construction
    1.  9.02 Special Construction
    2.  9.03 Stair Design
    3.  9.04 Stair Requirements
    4.  9.05 Stair Requirements
    5.  9.06 Stair Plans
    6.  9.07 Stair Plans
    7.  9.08 Wood Stairs
    8.  9.09 Wood Stairs
    9.  9.10 Concrete Stairs
    10.  9.11 Steel Stairs
    11.  9.12 Spiral Stairs
    12.  9.13 Ladders
    13.  9.14 Elevators
    14.  9.15 Elevators
    15.  9.16 Elevators
    16.  9.17 Escalators
    17.  9.18 Fireplaces
    18.  9.19 Fireplace Requirements
    19.  9.20 Masonry Chimneys
    20.  9.21 Prefabricated Fireplaces & Stoves
    21.  9.22 Kitchen Layouts
    22.  9.23 Kitchen Dimensions
    23.  9.24 Kitchen Cabinets
    24.  9.25 The Kitchen Space
    25.  9.26 Bathroom Layouts
    26.  9.27 Plumbing Fixtures
    27.  9.28 Accessible Fixtures
    28.  9.29 Accessible Fixtures
    29.  9.30 The Bathroom Space
  11.  Chapter 10: Finish Work
    1.  10.02 Finish Work
    2.  10.03 Plaster
    3.  10.04 Plaster Lath & Accessories
    4.  10.05 Plaster Partition Systems
    5.  10.06 Plaster Details
    6.  10.07 Plaster Over Masonry
    7.  10.08 Plaster Ceilings
    8.  10.09 Gypsum Board
    9.  10.10 Gypsum Board Application
    10.  10.11 Gypsum Board Details
    11.  10.12 Ceramic Tile
    12.  10.13 Ceramic Tile Applications
    13.  10.14 Ceramic Tile Details
    14.  10.15 Terrazzo Flooring
    15.  10.16 Wood Flooring
    16.  10.17 Wood Flooring Installation
    17.  10.18 Stone Flooring
    18.  10.19 Resilient Flooring
    19.  10.20 Carpeting
    20.  10.21 Carpeting
    21.  10.22 Acoustical Ceiling Tiles
    22.  10.23 Suspended Acoustical Ceilings
    23.  10.24 Wood Joints
    24.  10.25 Wood Joints
    25.  10.26 Wood Moldings & Trim
    26.  10.27 Wood Moldings & Trim
    27.  10.28 Wood Paneling
    28.  10.29 Plywood Veneer
    29.  10.30 Plastic Laminate
  12.  Chapter 11: Mechanical & Electrical Systems
    1.  11.02 Mechanical & Electrical Systems
    2.  11.03 Thermal Comfort
    3.  11.04 Comfort Zone
    4.  11.05 Psychrometric Charts
    5.  11.06 Heating & Cooling Systems
    6.  11.07 Alternative Energy Sources
    7.  11.08 Alternative Energy Sources
    8.  11.09 Heating & Cooling Loads
    9.  11.10 Forced-Air Heating
    10.  11.11 Hot-Water Heating
    11.  11.12 Electric Heating
    12.  11.13 Radiant Heating
    13.  11.14 Radiant Heating
    14.  11.15 Active Solar Energy Systems
    15.  11.16 Cooling Systems
    16.  11.17 Hvac Systems
    17.  11.18 Hvac Systems
    18.  11.19 Hvac Systems
    19.  11.20 Hvac Systems
    20.  11.21 Air Distribution Outlets
    21.  11.22 Water Supply
    22.  11.23 Water Supply Systems
    23.  11.24 Water Supply Systems
    24.  11.25 Fire Protection Systems
    25.  11.26 Plumbing Fixtures
    26.  11.27 Sanitary Drainage Systems
    27.  11.28 Sanitary Drainage Systems
    28.  11.29 Sewage Disposal Systems
    29.  11.30 Electric Power
    30.  11.31 Electrical Service
    31.  11.32 Electrical Service
    32.  11.33 Electrical Circuits
    33.  11.34 Electrical Wiring
    34.  11.35 Access Flooring Systems
    35.  11.36 Electrical Outlets
    36.  11.37 Light
    37.  11.38 Light & Vision
    38.  11.39 Light Sources
    39.  11.40 Light Sources
    40.  11.41 Light Sources
    41.  11.42 Light Sources
    42.  11.43 Luminaires
    43.  11.44 Lighting
    44.  11.45 Lighting
    45.  11.46 Lighting
  13.  Chapter 12: Notes on Materials
    1.  12.02 Building Materials
    2.  12.03 Life-Cycle Assessment
    3.  12.04 Concrete
    4.  12.05 Concrete
    5.  12.06 Masonry
    6.  12.07 Masonry
    7.  12.08 Steel
    8.  12.09 Nonferrous Metals
    9.  12.10 Stone
    10.  12.11 Wood
    11.  12.12 Wood
    12.  12.13 Lumber
    13.  12.14 Wood Panel Products
    14.  12.15 Plastics
    15.  12.16 Glass
    16.  12.17 Glass Products
    17.  12.18 Nails
    18.  12.19 Screws & Bolts
    19.  12.20 Miscellaneous Fastenings
    20.  12.21 Paints & Coatings
    21.  12.22 Paints & Coatings
  14.  A: Appendix
    1.  A.02 Human Dimensions
    2.  A.03 ADA Accessibility Guidelines
    3.  A.04 Furniture Dimensions
    4.  A.05 Furniture Dimensions
    5.  A.06 Building Live Loads
    6.  A.07 Weights of Materials
    7.  A.08 Metric Conversion Factors
    8.  A.09 Metric Conversion Factors
    9.  A.10 Means of Egress
    10.  A.11 Means of Egress
    11.  A.12 Fire-Rated Construction
    12.  A.13 Fire-Rated Construction
    13.  A.14 Acoustics
    14.  A.15 Acoustics
    15.  A.16 Sound Control
    16.  A.17 Sound Control
    17.  A.18 Graphic Material Symbols
    18.  A.19 CSI Masterformat
    19.  A.20 CSI Masterformat
    20.  A.21 CSI Masterformat
    21.  A.22 CSI Masterformat
    22.  A.23 Uniformat II
    23.  A.24 Uniformat II
    24.  A.25 Uniformat II
    25.  A.26 Leed Green Building Rating System
    26.  A.27 Professional & Trade Associations
    27.  A.28 Professional & Trade Associations
    28.  A.29 Professional & Trade Associations
    29.  A.30 Professional & Trade Associations
  15.  Bibliography
  16.  Index
  17.  End User License Agreement

## Guide

  1.  Cover
  2.  Table of Contents
  3.  Preface

# Building Construction  
Illustrated

**Fifth Edition**

**Francis D. K. Ching**

Copyright © 2013 by John Wiley & Sons.  All rights reserved

Published by John Wiley & Sons, Inc., Hoboken, New Jersey  
Published simultaneously in Canada

No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600, or on the web at www.copyright.com.  Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at www.wiley.com/go/permissions. 

Limit of Liability/Disclaimer of Warranty: While the publisher and author have used their best efforts in preparing this book, they make no representations or warranties with the respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose.  No warranty may be created or extended by sales representatives or written sales materials.  The advice and strategies contained herein may not be suitable for your situation.  You should consult with a professional where appropriate.  Neither the publisher nor the author shall be liable for damages arising herefrom. 

For general information about our other products and services, please contact our Customer Care Department within the United States at (800) 762-2974, outside the United States at (317) 572-3993 or fax (317) 572-4002. 

Wiley publishes in a variety of print and electronic formats and by print-on-demand.  Some material included with standard print versions of this book may not be included in e-books or in print-on-demand.  If this book refers to media such as a CD or DVD that is not included in the version you purchased, you may download this material at <http://booksupport.wiley.com>.  For more information about Wiley products, visit www.wiley.com. 

Library of Congress Cataloging-in-Publication Data:

Ching, Frank, 1943-  
Building construction illustrated / Francis D. K. Ching. --  Fifth edition.   
pages cm  
Includes index.   
ISBN 978-1-118-45834-1 (pbk.)   
1.  Building.  2.  House construction.  I. Title.   
TH146.C52 2014  
690--dc23  
2013016213

# Preface

The first edition of this illustrated guide to building construction appeared in 1975, introducing students and builders of architecture to the fundamental principles that govern how buildings are erected.  It marked the emergence of a visual approach to understanding the relationship between design and construction. 

In 1991, the second edition provided a more expansive survey of building construction by adding coverage of structural steel, reinforced concrete, and curtain wall systems.  The third edition in 2001 remained a comprehensive introduction to the principles underlying building construction while refining the graphic format and organization of the first two editions, incorporating an expanded discussion of structural principles, elements, and systems and referencing the Americans with Disabilities Act Accessibility Guidelines and the MasterFormat™ system established by the Constructions Specifications Institute (CSI) for organizing construction information. 

The fourth edition in 2008 introduced the LEED® Green Building Rating System™ in Chapter One and referenced specific LEED criteria wherever appropriate; updated section numbers to correspond to the 2004 edition of the CSI MasterFormat™ system; and complied with the requirements of the 2006 edition of the International Building Code®. 

A common thread that wove itself through the first four editions and continues in this fifth edition is the attitude that buildings and sites should be planned and developed in an environmentally sensitive manner, responding to context and climate to reduce their reliance on active environmental control systems and the energy they consume.  This edition therefore continues to reference the latest edition of the LEED® Green Building Rating System™ criteria and the section numbers of the 2012 CSI MasterFormat™ system wherever appropriate.  Many of the changes and additions in this fifth edition, such as updating information in lighting technologies and ways in which to reduce energy usage in buildings, are incremental and often subtle, but together they comprise a continuing commitment to build wisely and sustainably. 

It would be nearly impossible to cover all building materials and construction techniques, but the information presented herein should be applicable to most residential and commercial construction situations encountered today.  Construction techniques continue to adjust to the development of new building materials, products, and standards.  What does not change are the fundamental principles that underlie building elements and the ways in which systems are constructed.  This illustrated guide focuses on these principles, which can serve as guideposts when evaluating and applying new information encountered in the planning, design, and construction of a building. 

Each building element, component, or system is described in terms of its end use.  The specific form, quality, capability, and availability of an element or component will vary with manufacturer and locale.  It is therefore important to always follow the manufacturer's recommendation in the use of a material or product and to pay careful attention to the building code requirements in effect for the use and location of a planned building.  It is the user's responsibility to ascertain the appropriateness of the information contained in this handbook and to judge its fitness for any particular purpose.  Seek the expert advice of a professional when needed. 

### **Metric Equivalents**

The International System of Units is an internationally accepted system of coherent physical units, using the meter, kilogram, second, ampere, kelvin, and candela as the base units of length, mass, time, electric current, temperature, and luminous intensity.  To acquaint the reader with the International System of Units, metric equivalents are provided throughout this book according to the following conventions:

  * All whole numbers in parentheses indicate millimeters unless otherwise noted. 
  * Dimensions 3 inches and greater are rounded to the nearest multiple of 5 millimeters. 
  * Nominal dimensions are directly converted; for example, a nominal 2 × 4 is converted to 51 × 100 even though its actual 1-½" × 3-½" dimensions would be converted to 38 × 90. 
  * Note that 3487 mm = 3.487 m.
  * In all other cases, the metric unit of measurement is specified. 
  * Refer to the Appendix for metric conversion factors. 

# **Chapter 1**  
 **THE BUILDING SITE**

1.02 Building in Context

1.03 Sustainability

1.04 Green Building

1.05 LEED® Green Building Rating System

1.06 The 2030 Challenge

1.07 Site Analysis

1.08 Soils

1.09 Soil Mechanics

1.10 Topography

1.12 Plant Materials

1.13 Trees

1.14 Solar Radiation

1.16 Passive Solar Design

1.18 Solar Shading

1.19 Daylighting

1.20 Precipitation

1.21 Site Drainage

1.22 Wind

1.23 Sound & Views

1.24 Regulatory Factors

1.25 Zoning Ordinances

1.26 Site Access & Circulation

1.27 Pedestrian Circulation

1.28 Vehicular Circulation

1.29 Vehicular Parking

1.30 Slope Protection

1.31 Retaining Walls

1.34 Paving

1.36 The Site Plan

1.38 Site Description

## **1.02 BUILDING IN CONTEXT**

Buildings do not exist in isolation.  They are conceived to house, support, and inspire a range of human activities in response to sociocultural, economic, and political needs, and are erected in natural and built environments that constrain as well as offer opportunities for development.  We should therefore carefully consider the contextual forces that a site presents in planning the design and construction of buildings. 

The microclimate, topography, and natural habitat of a site all influence design decisions at a very early stage in the design process.  To enhance human comfort as well as conserve energy and material resources, responsive and sustainable design respects the indigenous qualities of a place, adapts the form and layout of a building to the landscape, and takes into account the path of the sun, the rush of the wind, and the flow of water on a site. 

In addition to environmental forces, there exist the regulatory forces of zoning ordinances.  These regulations take into account existing land-use patterns and prescribe the acceptable uses and activities for a site as well as limit the size and shape of the building mass and where it may be located on the site. 

Just as environmental and regulatory factors influence where and how development occurs, the construction, use, and maintenance of buildings inevitably place a demand on transportation systems, utilities, and other services.  A fundamental question we face is how much development a site can sustain without exceeding the capacity of these service systems, consuming too much energy, or causing environmental damage. 

Consideration of these contextual forces on site and building design cannot proceed without a brief discussion of sustainability. 

## **1.03 SUSTAINABILITY**

In 1987, the United Nations World Commission on Environment and Development, chaired by Gro Harlem Brundtland, former Prime Minister of Norway, issued a report, Our Common Future.  Among its findings, the report defined sustainable development as "a form of development that meets the needs of the present without compromising the ability of future generations to meet their own needs." 

Increasing awareness of the environmental challenges presented by climate change and resource depletion has pushed sustainability into becoming a significant issue shaping how the building design industry operates.  Sustainability is necessarily broad in scope, affecting how we manage resources as well as build communities, and the issue calls for a holistic approach that considers the social, economic, and environmental impacts of development and requires the full participation of planners, architects, developers, building owners, contractors, manufacturers, as well as governmental and non-governmental agencies. 

In seeking to minimize the negative environmental impact of development, sustainability emphasizes efficiency and moderation in the use of materials, energy, and spatial resources.  Building in a sustainable manner requires paying attention to the predictable and comprehensive outcomes of decisions, actions, and events throughout the life cycle of a building, from conception to the siting, design, construction, use, and maintenance of new buildings as well as the renovation process for existing buildings and the reshaping of communities and cities. 

## **1.04 GREEN BUILDING**

The terms "green building" and "sustainable design" are often used interchangeably to describe any building designed in an environmentally sensitive manner.  However, sustainability calls for a whole-systems approach to development that encompasses the notion of green building but also addresses broader social, ethical, and economic issues, as well as the community context of buildings.  As an essential component of sustainability, green building seeks to provide healthy environments in a resource-efficient manner using ecologically based principles. 

Green building is increasingly governed by standards, such as the Leadership in Energy and Environmental Design (LEED®) Green Building Rating System™, which provides a set of measurable criteria that promote environmentally sustainable construction.  The rating system was developed by the U.S. Green Building Council (USGBC) as a consensus among its members—federal/state/local agencies, suppliers, architects, engineers, contractors, and building owners—and is continually being evaluated and refined in response to new information and feedback.  In July 2003 Canada obtained a license from the USGBC to adapt the LEED rating system to Canadian circumstances. 

### **LEED ®**

To aid designers, builders, and owners achieve LEED certification for specific building types and phase of a building life cycle, the USGBC has developed a number of versions of the LEED rating system:

  * LEED for New Construction and Major Renovations
  * LEED for Existing Buildings: Operations & Maintenance
  * LEED for Commercial Interiors
  * LEED for Core & Shell
  * LEED for Schools
  * LEED for Retail
  * LEED for Healthcare
  * LEED for Homes
  * LEED for Neighborhood Development

The LEED rating system for new construction addresses seven major areas of development. 

**1.  Sustainable Sites**

deals with reducing the pollution associated with construction activity, selecting sites appropriate for development, protecting environmentally sensitive areas and restoring damaged habitats, encouraging alternative modes of transportation to reduce the impact of automobile use, respecting the natural water hydrology of a site, and reducing the effects of heat islands. 

**2.  Water Efficiency**

promotes reducing the demand for potable water and the generation of wastewater by using water-conserving fixtures, capturing rainwater or recycled graywater for conveying sewage, and treating wastewater with on-site systems. 

## 1.05 LEED® GREEN BUILDING RATING SYSTEM

**3.  Energy and Atmosphere**

encourages increasing the efficiency with which buildings and their sites acquire and use energy, increasing renewable, nonpolluting energy sources to reduce the environmental and economic impacts associated with fossil fuel energy use, and minimizing the emissions that contribute to ozone depletion and global warming. 

**4.  Materials and Resources**

seeks to maximize the use of locally available, rapidly renewable and recycled materials, reduce waste and the demand for virgin materials, retain cultural resources, and minimize the environmental impacts of new buildings. 

**5.  Indoor Environmental Quality**

promotes the enhanced comfort, productivity, and well-being of building occupants by improving indoor air quality, maximizing daylighting of interior spaces, enabling user control of lighting and thermal comfort systems to suit task needs and preferences, and minimizing the exposure of building occupants to potentially hazardous particulates and chemical pollutants, such as the volatile organic compounds (VOC) contained in adhesives and coatings and the urea-formaldehyde resins in composite wood products. 

**6.  Innovation in Design**

rewards exceeding the requirements set by the LEED Green Building Rating System and/or demonstrating innovative performance in Green Building categories not specifically addressed by the LEED Green Building Rating System. 

**7.  Regional Priority**

provides incentives for practices that address geographically-specific environmental priorities. 

## **1.06 THE 2030 CHALLENGE**

Architecture 2030 is an environmental advocacy group whose mission is "to provide information and innovative solutions in the fields of architecture and planning, in an effort to address global climate change."  Its founder, New Mexico architect Edward Mazria, points to data from the U.S. Energy Information Administration that indicates buildings are responsible for almost half the total U.S. energy consumption and greenhouse gas (GHG) emissions annually; globally, Mazria believes the percentage is even greater. 

What is relevant to any discussion of sustainable design is that most of the building sector's energy consumption is not attributable to the production of materials or the process of construction, but rather to operational processes—the heating, cooling, and lighting of buildings.  This means that to reduce the energy consumption and GHG emissions generated by the use and maintenance of buildings over their life span, it is necessary to properly design, site, and shape buildings and incorporate natural heating, cooling, ventilation, and daylighting strategies. 

The 2030 Challenge issued by Architecture 2030 calls for all new buildings and developments to be designed to use half the fossil fuel energy they would typically consume, and that an equal amount of existing building area be renovated annually to meet a similar standard.  Architecture 2030 is further advocating that the fossil fuel reduction standard be increased from 70% in 2015 to 80% in 2020 and 90% in 2025, and that by 2030, all new buildings be carbon-neutral (using no fossil-fuel GHG-emitting energy to build and operate). 

There are two approaches to reducing a building's consumption of GHG-emitting fossil fuels.  The passive approach is to work with the climate in designing, siting, and orienting a building and employ passive cooling and heating techniques to reduce its overall energy requirements.  The active approach is to increase the ability of a building to capture or generate its own energy from renewable sources (solar, wind, geothermal, low-impact hydro, biomass, and bio-gas) that are available locally and in abundance.  While striking an appropriate, cost-effective balance between energy conservation and generating renewable energy is the goal, minimizing energy use is a necessary first step, irrespective of the fact that the energy may come from renewable resources. 

#### **Climate Change & Global Warming**

Greenhouse gases, such as carbon dioxide, methane, and nitrous oxide, are emissions that rise into the atmosphere.  CO2 accounts for the largest share of U.S. greenhouse gas emissions.  Fossil fuel combustion is the main source of CO2 emissions. 

## **1.07 SITE ANALYSIS**

Site analysis is the process of studying the contextual forces that influence how we might situate a building, lay out and orient its spaces, shape and articulate its enclosure, and establish its relationship to the landscape.  Any site survey begins with the gathering of physical site data. 

  * Draw the area and shape of the site as defined by its legal boundaries. 
  * Indicate required setbacks, existing easements, and rights-of-way. 
  * Estimate the area and volume required for the building program, site amenities, and future expansion, if desired. 

  * Analyze the ground slopes and subsoil conditions to locate the areas suitable for construction and outdoor activities. 
  * Identify steep and moderate slopes that may be unsuitable for development. 
  * Locate soil areas suitable for use as a drainage field, if applicable. 
  * Map existing drainage patterns. ( LEED SS Credits 6.1, 6.2: Stormwater Design)
  * Determine the elevation of the water table. 
  * Identify areas subject to excessive runoff of surface water, flooding, or erosion. 

  * Locate existing trees and native plant materials that should be preserved. 
  * Chart existing water features, such as wetlands, streams, watersheds, flood plains, or shorelines that should be protected. ( LEED SS Credit 5.1: Site Development—Protect or Restore Habitat)

  * Map climatic conditions: the path of the sun, the direction of prevailing winds, and the expected amount of rainfall. 
  * Consider the impact of landforms and adjacent structures on solar access, prevailing winds, and the potential for glare. 
  * Evaluate solar radiation as a potential energy source. 

  * Determine possible points of access from public roadways and public transit stops. ( LEED SS Credit 4.1: Alternative Transportation—Public Transportation Access)
  * Study possible circulation paths for pedestrians and vehicles from these access points to building entrances. 
  * Ascertain the availability of utilities: water mains, sanitary and storm sewers, gas lines, electrical power lines, telephone and cable lines, and fire hydrants. 
  * Determine access to other municipal services, such as police and fire protection. 

  * Identify the scope of desirable views as well as objectionable views. 
  * Cite potential sources of congestion and noise. 
  * Evaluate the compatibility of adjacent and proposed land uses. 
  * Map cultural and historical resources that should be preserved. 
  * Consider how the existing scale and character of the neighborhood or area might affect the building design. 
  * Map the proximity to public, commercial, medical, and recreational facilities. ( LEED SS Credit 2: Development Density and Community Connectivity)

## **1.08 SOILS**

There are two broad classes of soils—coarse-grained soils and fine-grained soils.  Coarse-grained soils include gravel and sand, which consist of relatively large particles visible to the naked eye; fine-grained soils, such as silt and clay, consist of much smaller particles.  The American Society for Testing and Materials (ASTM) Unified Soil Classification System further divides gravels, sands, silts, and clays into soil types based on physical composition and characteristics.  See table that follows. 

The soil underlying a building site may actually consist of superimposed layers, each of which contains a mix of soil types, developed by weathering or deposition.  To depict this succession of layers or strata called horizons, geotechnical engineers draw a soil profile, a diagram of a vertical section of soil from the ground surface to the underlying material, using information collected from a test pit or boring. 

The integrity of a building structure depends ultimately on the stability and strength under loading of the soil or rock underlying the foundation.  The stratification, composition, and density of the soil bed, variations in particle size, and the presence or absence of groundwater are all critical factors in determining the suitability of a soil as a foundation material.  When designing anything other than a single-family dwelling, it is advisable to have a geotechnical engineer undertake a subsurface investigation. 

A subsurface investigation (CSI MasterFormat™ 02 32 00) involves the analysis and testing of soil disclosed by excavation of a test pit up to 10′ (3 m) deep or by deeper test borings in order to understand the structure of the soil, its shear resistance and compressive strength, its water content and permeability, and the expected extent and rate of consolidation under loading.  From this information, the geotechnical engineer is able to gauge the anticipated total and differential settlement under loading by a proposed foundation system. 

## **1.09 SOIL MECHANICS**

The allowable bearing capacity of a soil is the maximum unit pressure a foundation is permitted to impose vertically or laterally on the soil mass.  In the absence of geotechnical investigation and testing, building codes may permit the use of conservative load-bearing values for various soil classifications.  While high-bearing-capacity soils present few problems, low-bearing-capacity soils may dictate the use of a certain type of foundation and load distribution pattern, and ultimately, the form and layout of a building. 

Density is a critical factor in determining the bearing capacity of granular soils.  The Standard Penetration Test measures the density of granular soils and the consistency of some clays at the bottom of a borehole, recording the number of blows required by a hammer to advance a standard soil sampler.  In some cases, compaction, by means of rolling, tamping, or soaking to achieve optimum moisture content, can increase the density of a soil bed. 

Coarse-grained soils have a relatively low percentage of void spaces and are more stable as a foundation material than silt or clay.  Clay soils, in particular, tend to be unstable because they shrink and swell considerably with changes in moisture content.  Unstable soils may render a site unbuildable unless an elaborately engineered and expensive foundation system is put in place. 

The shearing strength of a soil is a measure of its ability to resist displacement when an external force is applied, due largely to the combined effects of cohesion and internal friction.  On sloping sites, as well as during the excavation of a flat site, unconfined soil has the potential to displace laterally.  Cohesive soils, such as clay, retain their strength when unconfined; granular soils, such as gravel, sand, or some silts, require a confining force for their shear resistance and have a relatively shallow angle of repose. 

The water table is the level beneath which the soil is saturated with groundwater.  Some building sites are subject to seasonal fluctuations in the level of groundwater.  Any groundwater present must be drained away from a foundation system to avoid reducing the bearing capacity of the soil and to minimize the possibility of water leaking into a basement.  Coarse-grained soils are more permeable and drain better than fine-grained soils, and are less susceptible to frost action. 

## **1.10 TOPOGRAPHY**

Topography refers to the configuration of surface features of a plot of land, which influences where and how to build and develop a site.  To study the response of a building design to the topography of a site, we can use a series of site sections or a site plan with contour lines. 

Contour lines are imaginary lines joining points of equal elevation above a datum or bench mark.  The trajectory of each contour line indicates the shape of the land formation at that elevation.  Note that contour lines are always continuous and never cross one another; they coincide in a plan view only when they cut across a vertical surface. 

Contour interval refers to the difference in elevation represented by any two adjacent contour lines on a topographic map or site plan.  The interval used is determined by the scale of a drawing, the size of the site, and the nature of the topography.  The larger the area and the steeper the slopes, the greater the interval between contours.  For large or steeply sloping sites, 20′ or 40′ (5 or 10 m) contour intervals may be used.  For small sites having relatively gradual slopes, 1', 2', or 5′ (0.5 or 1.0 m) contours may be necessary. 

## **1.11 TOPOGRAPHY**

For aesthetic and economic, as well as ecological reasons, the general intent in developing a site should be to minimize the disturbance of existing landforms and features while taking advantage of natural ground slopes and the microclimate of the site. 

## **1.12 PLANT MATERIALS**

Plant materials provide aesthetic as well as functional benefits in conserving energy, framing or screening views, moderating noise, retarding erosion, and visually connecting a building to its site.  Factors to consider in the selection and use of plant materials in landscaping include the:

  * Tree structure and shape
  * Seasonal density, texture, and color of foliage
  * Speed or rate of growth
  * Mature height and spread of foliage
  * Requirements for soil, water, sunlight, and temperature range
  * Depth and extent of the root structure

  * Trees and other plant life adapt their forms to the climate. 

  * Existing healthy trees and native plant materials should be preserved whenever possible.  During construction and when regrading a site, existing trees should be protected for an area equal to the diameter of their crowns.  The root systems of trees planted too close to a building may disturb the foundation system.  Root structures can also interfere with underground utility lines. 
  * To support plant life, a soil must be able to absorb moisture, supply the appropriate nutrients, be capable of aeration, and be free of concentrated salts. 

Grass and other ground covers:

  * Can reduce air temperature by absorbing solar radiation and encouraging cooling by evaporation;
  * Aid in stabilizing soil embankments and preventing erosion;
  * Increase the permeability of soil to air and water. 

  * Vines can reduce the heat transmission through a sunlit wall by providing shade and cooling the immediate environment by evaporation. 

**CSI MasterFormat 32 90 00: Planting**

## **1.13 TREES**

### **Providing Shade**

The amount of solar radiation obstructed or filtered by a tree depends on its:

  * Orientation to the sun
  * Proximity to a building or outdoor space
  * Shape, spread, and height
  * Density of foliage and branch structure

  * Trees shade a building or outdoor space most effectively from the southeast during the morning and the southwest during the late afternoon when the sun has a low altitude and casts long shadows. 
  * South-facing overhangs provide more efficient shading during the midday period when the sun is high and casts short shadows. 
  * Deciduous trees provide shade and glare protection during the summer and allow solar radiation to penetrate through their branch structures during the winter. 
  * Evergreens provide shade throughout the year and help reduce snow glare during the winter. 

### **Serving as Windbreak**

  * Evergreens can form effective windbreaks and reduce heat loss from a building during the winter. 
  * The foliage of plant materials reduces wind-blown dust. 

### **Defining Space**

  * Trees can shape outdoor spaces for activity and movement. 

### **Directing or Screening Views**

  * Trees can frame desirable views. 
  * Trees can screen undesirable views and provide privacy for outdoor spaces. 

### **Attenuating Sound**

  * A combination of deciduous and evergreen trees is most effective in intercepting and attenuating airborne sound, especially when combined with earth mounds. 

### **Improving Air Quality**

  * Trees trap particulate matter on their leaves, which is then washed to the ground during rainfall. 
  * Leaves can also assimilate gaseous and other pollutants. 
  * Photosynthetic process can metabolize fumes and other odors. 

### **Stabilizing Soil**

  * The root structures of trees aid in stabilizing soil, increasing the permeability of the soil to water and air, and preventing erosion. 

## **1.14 SOLAR RADIATION**

The location, form, and orientation of a building and its spaces should take advantage of the thermal, hygienic, and psychological benefits of sunlight.  Solar radiation, however, may not always be beneficial, depending on the latitude and climate of the site.  In planning the design of a building, the objective should be to maintain a balance between underheated periods when solar radiation is beneficial and overheated periods when radiation should be avoided. 

The path of the sun through the sky varies with the seasons and the latitude of a building site.  The range of solar angles for a specific site should be obtained from a weather almanac or service bureau before calculating the potential solar heat gain and shading requirements for a building design. 

## **1.15 SOLAR RADIATION**

The following are recommended forms and orientations for isolated buildings in different climatic regions.  The information presented should be considered along with other contextual and programmatic requirements. 

### **Cool Regions**

Minimizing the surface area of a building reduces exposure to low temperatures. 

  * Maximize absorption of solar radiation. 
  * Reduce radiant, conductive, and evaporative heat loss. 
  * Provide wind protection. 

### **Temperate Regions**

Elongating the form of a building along the east-west axis maximizes south-facing walls. 

  * Minimize east and west exposures, which are generally warmer in summer and cooler in winter than southern exposures. 
  * Balance solar heat gain with shade protection on a seasonal basis. 
  * Encourage air movement in hot weather; protect against wind in cold weather. 

### **Hot-Arid Regions**

Building forms should enclose courtyard spaces. 

  * Reduce solar and conductive heat gain. 
  * Promote cooling by evaporation using water features and plantings. 
  * Provide solar shading for windows and outdoor spaces. 

### **Hot-Humid Regions**

Building form elongated along the east-west axis minimizes east and west exposures. 

  * Reduce solar heat gain. 
  * Utilize wind to promote cooling by evaporation. 
  * Provide solar shading for windows and outdoor spaces. 

LEED EA Credit 1: Optimize Energy Performance

## **1.16 PASSIVE SOLAR DESIGN**

Passive solar heating refers to using solar energy to heat the interior spaces of a building without relying on mechanical devices that require additional energy.  Passive solar systems rely instead on the natural heat transfer processes of conduction, convection, and radiation for the collection, storage, distribution, and control of solar energy. 

  * The solar constant is the average rate at which radiant energy from the sun is received by the earth, equal to 430 Btu per square foot per hour (1353 W/m2/hr), used in calculating the effects of solar radiation on buildings. 

There are two essential elements in every passive solar system:

**CSI MasterFormat 23 56 00: Solar Energy Heating Equipment**

## **1.17 PASSIVE SOLAR DESIGN**

### **Direct Gain**

Direct gain systems collect heat directly within an interior space.  The surface area of the storage mass, which is incorporated into the space, should be 50% to 66% of the total surface area of the space.  During the cooling season, operable windows and walls are used for natural or induced ventilation. 

### **Indirect Gain**

Indirect gain systems control heat gain at the exterior skin of a building.  The solar radiation first strikes the thermal mass, either a concrete or masonry Trombe wall, or a drumwall of water-filled barrels or tubes, which is located between the sun and the living space.  The absorbed solar energy moves through the wall by conduction and then to the space by radiation and convection. 

### **Sunspace**

A sunroom or solarium is another medium for indirect heat gain.  The sunspace, having a floor of high thermal mass, is separated from the main living space by a thermal storage wall from which heat is drawn as needed.  For cooling, the sunspace can be vented to the exterior. 

### **Roof Pond**

Another form of indirect gain is a roof pond that serves as a liquid mass for absorbing and storing solar energy.  An insulating panel is moved over the roof pond at night, allowing the stored heat to radiate downward into the space.  In summer, the process is reversed to allow internal heat absorbed during the day to radiate to the sky at night. 

### **Isolated Gain**

Isolated gain systems collect and store solar radiation away from the space to be heated.  As air or water in a collector is warmed by the sun, it rises to the served space or is stored in the thermal mass until needed.  Simultaneously, cooler air or water is pulled from the bottom of the thermal storage, creating a natural convection loop. 

## **1.18 SOLAR SHADING**

Shading devices shield windows and other glazed areas from direct sunlight in order to reduce glare and excessive solar heat gain in warm weather.  Their effectiveness depends on their form and orientation relative to the solar altitude and azimuth for the time of day and season of the year.  Exterior devices are more efficient than those located within interior spaces because they intercept solar rays before they can reach an exterior wall or window. 

Illustrated are basic types of solar shading devices.  Their form, orientation, materials, and construction may vary to suit specific situations.  Their visual qualities of pattern, texture, and rhythm, and the shadows they cast, should be considered when designing the facades of a building. 

  * Horizontal overhangs are most effective when they have southern orientations. 

  * Horizontal louvers parallel to a wall permit air circulation near the wall and reduce conductive heat gain. 
  * Louvers may be operated manually or controlled automatically with time or photoelectric controls to adapt to the solar angle. 

  * Slanted louvers provide more protection than those parallel to a wall. 
  * Angle varies according to the range of solar angles. 

  * Louvers hung from a solid overhang protect against low sun angles. 
  * Louvers may interfere with view. 

  * Vertical louvers are most effective for eastern or western exposures. 
  * Louvers may be operated manually or controlled automatically with time or photoelectric controls to adapt to solar angle. 
  * Separation from wall reduces conductive heat gain. 

  * Eggcrates combine the shading characteristics of horizontal and vertical louvers and have a high shading ratio. 
  * Eggcrates, sometimes referred to as brise-soleil, are very efficient in hot climates. 

  * Solar blinds and screens can provide up to a 50% reduction in solar radiation, depending on their reflectivity. 
  * Heat-absorbing glass can absorb up to 40% of the radiation reaching its surface. 

  * Trees and adjacent structures may provide shade depending on their proximity, height, and orientation. 

**CSI MasterFormat 10 71 13: Exterior Sun Control Devices**

## **1.19 DAYLIGHTING**

Solar radiation provides not only heat but also light for the interior spaces of a building.  This daylight has psychological benefits as well as practical utility in reducing the amount of energy required for artificial lighting.  While intense, direct sunlight varies with the time of day, from season to season, and from place to place, it can be diffused by cloud cover, haze, and precipitation, and reflected from the ground and other surrounding surfaces. 

The level of illumination provided by daylight diminishes as it penetrates an interior space.  Generally, the larger and higher a window is, the more daylight will enter a room. 

Excessive brightness ratios can lead to glare and impairment of visual performance.  Glare can be controlled by the use of shading devices, the proper orientation of task surfaces, and allowing daylight to enter a space from at least two directions. 

## **1.20 PRECIPITATION**

The amount of annual and seasonal precipitation expected for a building site should influence the design and construction of the roof structure of a building, the choice of building materials, and the detailing of its exterior wall assemblies.  Furthermore, the runoff of rain and melting snow from constructed roof areas and paved surfaces increases the amount of storm water that must be drained from the site. 

  * See Chapter 6 for constructing roof systems. 
  * See Chapter 7 for roofing assemblies. 

## **1.21 SITE DRAINAGE**

Development of a site can disrupt the existing drainage pattern and create additional water flow from constructed roof areas and paved surfaces.  Limiting disruption of a site's natural water hydrology and promoting infiltration by such means as pervious paving and vegetated roofs is advisable.  Site drainage is necessary to prevent erosion and the collection of excess surface water or groundwater resulting from new construction. 

There are two basic types of site drainage: subsurface and surface drainage systems.  Subsurface drainage consists of an underground network of piping for conveying groundwater to a point of disposal, as a storm sewer system or a natural outfall at a lower elevation on the site.  Excess groundwater can reduce the load-carrying capacity of a foundation soil and increase the hydrostatic pressure on a building foundation.  Waterproofing is required for basement structures situated close to or below the water table of a site. 

Surface drainage refers to the grading and surfacing of a site in order to divert rain and other surface water into natural drainage patterns or a municipal storm sewer system.  A holding pond may be necessary when the amount of surface runoff exceeds the capacity of the storm sewer system. 

## **1.22 WIND**

The direction and velocity of prevailing winds are important site considerations in all climatic regions.  The seasonal and daily variations in wind should be carefully considered in evaluating its potential for ventilating interior spaces and outdoor courtyards in warm weather, causing heat loss in cold weather, and imposing lateral loads on a building structure. 

Wind-induced ventilation of interior spaces aids in the air exchange necessary for health and odor removal.  In hot weather, and especially in humid climates, ventilation is beneficial for convective or evaporative cooling.  Natural ventilation also reduces the energy required by mechanical fans and equipment. ( LEED IEQ Credit 2: Increased Ventilation)

The movement of air through a building is generated by differences in air pressure as well as temperature.  The resulting patterns of air flow are affected more by building geometry and orientation than by air speed. 

The ventilation of concealed roof and crawl spaces is required to remove moisture and control condensation.  In hot weather, attic ventilation can also reduce overhead radiant heat gain. 

In cold climates, a building should be buffered against chilling winds to reduce infiltration into interior spaces and lower heat loss.  A windbreak may be in the form of an earth berm, a garden wall, or a dense stand of trees.  Windbreaks reduce wind velocity and produce an area of relative calm on their leeward side.  The extent of this wind shadow depends on the height, depth, and density of the windbreak, its orientation to the wind, and the wind velocity. 

  * A partially penetrable windscreen creates less pressure differential, resulting in a large wind shadow on the leeward side of the screen. 

The structure, components, and cladding of a building must be anchored to resist wind-induced overturning, uplift, and sliding.  Wind exerts positive pressure on the windward surfaces of a building and on windward roof surfaces having a slope greater than 30°.  Wind exerts negative pressure or suction on the sides and leeward surfaces and normal to windward roof surfaces having a slope less than 30°.  See 2.09 for more information on wind forces. 

## **1.23 SOUND & VIEWS**

Sound requires a source and a path.  Undesirable exterior sounds or noise may be caused by vehicular traffic, aircraft, and other machinery.  The sound energy they generate travels through the air outward from the source in all directions in a continuously expanding wave.  This sound energy, however, lessens in intensity as it disperses over a wide area.  To reduce the impact of exterior noise, therefore, the first consideration should be distance—locating a building as far from the noise source as possible.  When the location or dimensions of a site do not make this possible, then the interior spaces of a building may be screened from the noise source in the following ways. 

  * Use building zones where noise can be tolerated, for example, mechanical, service, and utility areas, as a buffer. 
  * Employ building materials and construction assemblies designed to reduce the transmission of airborne and structure-borne sound. 
  * Orient door and window openings away from the sources of undesirable noise. 
  * Place physical mass, such as earth berms, between the noise source and the building. 
  * Utilize dense plantings of trees and shrubs, which can be effective in diffusing or scattering sound. 
  * Plant grass or other ground cover, which is more absorptive than the hard, reflective surfaces of pavements. 

An important aspect of site planning is orienting the interior spaces of a building to the amenities and features of a site.  Given the appropriate orientation, window openings in these spaces should be positioned not only to satisfy the requirements for natural light and ventilation, but also to reveal and frame desirable views.  Depending on the location of the site, these views may be close or distant in nature.  Even when desirable views are nonexistent, a pleasant outlook can often be created within a building site through landscaping. 

A window may be created within a wall in a number of ways, depending on the nature of the view and the way it is framed in the wall construction.  It is important to note that the size and location of windows also affect the spatial quality and daylighting of a room, and the potential for heat loss or gain. 

  * South-facing windows can be effectively shaded while admitting daylight. 
  * North-facing windows are exposed to winter winds in cool climates. 
  * East- and west-facing windows are sources of overheating and are difficult to shade effectively. 

## **1.24 REGULATORY FACTORS**

Zoning ordinances are enacted within a municipality or land-use district to manage growth, regulate land-use patterns, control building density, direct development to areas with adequate services and amenities, protect environmentally sensitive areas, and conserve open space. 

For any single building site, a zoning ordinance will regulate both the types of activity that may occur on it and the location and bulk of the building or buildings constructed to house such activities.  A special type of zoning ordinance is the Planned Unit Development, which allows a fairly large tract of land to be developed as a single entity for added flexibility in the placement, grouping, size, and use of structures. 

It is important to understand how a zoning ordinance might constrain the allowable size and shape of a building.  The bulk of a building is regulated directly by specifying various aspects of its size. 

  * Percentage of allowable lot coverage = (C × D) / ( A × B)
  * Percentage of allowable total floor area = [(C × D) + (E × F) + (G × H)] / (A × B)

  * How much of the land can be covered by a building structure and the total floor area that may be constructed are expressed as percentages of the lot area. 

  * Percentage of allowable width or depth = C/A or D/B

## **1.25 ZONING ORDINANCES**

Exclusions to the general requirements of a zoning ordinance may exist in the form of exceptions or allowances.  Exceptions to the normal setback requirements may be made for:

  * Projections of architectural features such as roof overhangs, cornices, bay windows, and balconies
  * Accessory structures such as low-level decks, fences, and detached carports or garages
  * Precedents set by existing, neighboring structures

Exceptions are often made for sloping sites, or for sites adjacent to public open spaces. 

  * Sloping roofs, chimneys, and other roof projections may be allowed to extend beyond the normal height limitation. 
  * The height limit may be directly related to the slope of a site. 
  * A reduction in the setback requirements may be made for sloping sites or for sites fronting on open space. 

In order to provide for adequate light, air, and space, and to enhance the streetscape and pedestrian environment, requirements may exist for:

  * Open spaces accessible to the public  
(LEED SS Credit 5.2: Site Development—Maximize Open Space)
  * Additional setbacks if a structure rises above a certain height
  * Modulation of the facade of a building fronting a public space
  * Vehicular access and off-street parking

Zoning ordinances may also contain requirements that apply only to specific use categories as well as procedures for requesting a variance from the regulations. 

  * Restrictive covenants are provisions in a deed that restrict the action of any party to it, as an agreement among property owners specifying the use to which a property can be put.  Racial and religious restrictions are legally unenforceable. 

Other regulatory instruments exist that affect the way buildings are sited and constructed.  These statutes—commonly referred to as the building code—establish the relationship between:

  * The type of occupancy a building houses
  * The fire-resistance rating of its structure and construction
  * The allowable height and floor areas of the building, and its separation from neighboring structures

  * See 2.05 for more information on building codes. 

## **1.26 SITE ACCESS & CIRCULATION**

Providing for access and circulation for pedestrians, automobiles, and service vehicles is an important aspect of site planning, which influences both the location of a building on its site and the orientation of its entrances.  Outlined here and on the following pages are fundamental criteria for estimating and laying out the space required for walkways, roadways, and surface parking. 

**1.**  Provide for safe and convenient pedestrian access and movement to building entrances from parking areas or public transit stops with minimal crossing of roadways. 

**2.**  Determine the number of parking spaces required by the zoning ordinance for the type of occupancy and total number of units or floor area of the building. 

**3.**  Determine the number of accessible parking spaces as well as curb cuts, ramps, and paths to accessible building entrances required by local, state, or federal law. 

**4.**  Provide loading zones for buses and other public transportation vehicles where applicable. 

**5.**  Separate service and truck loading areas from pedestrian and automobile traffic. 

**6.**  Furnish access for emergency vehicles such as fire trucks and ambulances. 

**7.**  Establish the required width and location of curb cuts and their proper distance from public street intersections. 

**8.**  Ensure clear sight lines for vehicles entering public roadways. 

**9.**  Plan for control of access to parking areas where required. 

**10.**  Provide space for landscaping; screening of parking areas may be required by zoning ordinance. 

**11.**  Slope paved walkways and parking areas for drainage. 

**12.**  Provide space for snow removal equipment in cold climates. 

  * Illustration adapted from the site plan for the Carré House, designed by Alvar Aalto. 

## **1.27 PEDESTRIAN CIRCULATION**

### **Pedestrian Walks**

  * Minimize conflicts with roadways and parking areas. 
  * Provide traction in areas subject to icy conditions. 
  * 0.5% minimum slope for drainage; 1.5% preferred

### **Exterior Stairs**

  * Minimum of three risers per run of stairs
  * Handrails are required for stairs having four or more risers, or where icy conditions exist. 

### **Bike Paths**

  * Provide amenities, such as benches, trash containers, and lighting. 

### **ADA Accessibility Guidelines**

  * Avoid surface irregularities that can impede wheelchair traffic. 
  * Provide tactile warning strips for the visually impaired at grade changes and hazardous vehicular areas. 
  * See A.03 for general ADA Accessibility Guidelines. 

### **Curb Ramps**

  * Curb ramps are required wherever an accessible route crosses a curb. 
  * Surface of ramp should be stable, firm, and slip-resistant. 

## **1.28 VEHICULAR CIRCULATION**

### **Private Roadways**

### **Residential Drives and Garages**

## **1.29 VEHICULAR PARKING**

### **Parking Lots**

### **Garage Ramps**

### **ADA Accessibility Guidelines**

  * Local, state, and federal laws regulate the number of accessible spaces required. 
  * Locate accessible parking spaces as close as possible to building or facility entrance. 
  * 1:50 maximum slope for spaces and access aisles
  * Accessible parking spaces for vans used by persons with disabilities should have a clear height of 9'-2" (2490) and an access aisle at least 8′ (2440) wide. 

  * Identify accessible parking spaces with a sign showing the international symbol of accessibility. 

## **1.30 SLOPE PROTECTION**

The principal mechanical means of protecting an embankment against erosion is a revetment of riprap or gabions. 

Cribbing or bin walls may also be used to hold back and protect steep embankments. 

Natural means of stabilization include soil binders—plant materials that inhibit or prevent erosion by providing a ground cover and forming a dense network of roots that bind the soil. 

## **1.31 RETAINING WALLS**

When a desired change in ground elevation exceeds the angle of repose of the soil, a retaining wall becomes necessary to hold back the mass of earth on the uphill side of the grade change. 

A retaining wall must be designed and constructed to resist the lateral pressure of the soil being retained.  This active pressure increases proportionally from zero at the upper grade level to a maximum value at the lowest depth of the wall.  The total pressure or thrust may be assumed to be acting through the centroid of the triangular distribution pattern, one-third above the base of the wall. 

  * T = 0.286 × SH2/ 2

  * T = total pressure or thrust

  * S = weight of retained soil; 100 pcf (1600 kg/m3) typical
  * W = composite weight of wall acting through centroid of the section
  * R = resultant of T and W

  * T = 0.833 × S(H + H')2/ 2 (for a retaining wall with surcharge)

A retaining wall may fail by overturning, horizontal sliding, or excessive settling. 

  * Thrust tends to overturn wall about toe of base. 
  * To prevent a retaining wall from overturning, the resisting moment (Mr) of the composite weight of the wall and any soil bearing on the heel of the base (W × d) must counter the overturning moment (Mo) created by the soil pressure (T × H/3).  Using a safety factor of 2, Mr ≥ 2Mo. 

  * To prevent a retaining wall from sliding, the composite weight of the wall times the coefficient of friction for the soil supporting the wall (W × C.F.) must counter the lateral thrust on the wall (T).  Using a safety factor of 1.5, W × C.F. ≥ 1.5T.

  * Average coefficients of friction: gravel, 0.6; silt/dry clay, 0.5; sand, 0.4; wet clay, 0.3

  * To prevent a retaining wall from settling, the vertical force (W) must not exceed the bearing capacity of the soil (B.C.), where W = weight of the wall and any soil bearing on the base plus the vertical component of the soil thrust for a wall with surcharge.  Using a safety factor of 1.5, B.C. ≥ 1.5 W/A.

## **1.32 RETAINING WALLS**

### **Reinforced Concrete Retaining Walls**

The proportioning guidelines below are for preliminary design only.  Consult a structural engineer for final design, especially when a retaining wall is to be built on poor soil or is subject to surcharge or live loads. 

### **Gravity Wall**

A gravity retaining wall resists overturning and sliding by the sheer weight and volume of its mass.  Gravity walls may be used for retaining structures less than 10′ (3048) high. 

### **T-Type Cantilevered Wall**

Cantilevered walls of reinforced concrete are used for retaining walls up to 20′ (6095) high.  Above this height, counterfort walls are employed. 

### **Counterfort Wall**

A counterfort wall utilizes triangular-shaped cross walls to stiffen the vertical slab and add weight to the base.  The counterforts are spaced at regular intervals equal to one-half the wall height. 

### **L-Type Cantilevered Wall**

This type of retaining wall is used when the wall abuts a property line or other obstruction. 

  * Drainage system may be required to relieve the buildup of water pressure behind the wall. 

  * Provide vertical control joints @ 25′ (7620) o.c.,  and vertical expansion joints every fourth control joint. 

**CSI MasterFormat 32 32 13: Cast-in-Place Concrete Retaining Walls**

## **1.33 RETAINING WALLS**

Timber and concrete, brick, or stone masonry may be used for relatively low retaining walls. 

### **Horizontal Timber Wall**

### **Brick Veneer Wall**

### **Dry Stone Wall**

**CSI MasterFormat 32 32 19: Unit Masonry Retaining Walls  
CSI MasterFormat 32 32 29: Timber Retaining Walls**

## **1.34 PAVING**

Paving provides a wearing surface for pedestrian or vehicular traffic on a site.  It is a composite structure whose thickness and construction are directly related to the type and intensity of traffic and loads to be carried, and the bearing capacity and permeability of the subgrade. 

Flexible pavements, consisting of concrete, brick, or stone unit pavers laid on a sand setting bed, are somewhat resilient and distribute loads to the subgrade in a radiating manner.  They require wood, steel, stone, masonry, or concrete edging to restrain the horizontal movement of the paving material.  Specially designed unit pavers may qualify as permeable or pervious paving that allows rainfall and stormwater to percolate to an underlying reservoir base where the runoff is either infiltrated to underlying soils or removed by a subsurface drain. 

(LEED SS Credits 6.1, 6.2: Stormwater Design)

Rigid pavements, such as reinforced concrete slabs or paving units mortared over a concrete slab, distribute their loads internally and transfer them to the subgrade over a broad area.  They require reinforcement and an extension of the base material along their edges. 

  * 1% minimum slope for drainage; highly textured paving may require a steeper slope. 

  * Brick paver: 4" × 4", 8", 12"; 1"–2" thick (100 × 100, 205, 305; 25–57 thick)

  * Concrete unit paver: 12", 18", 24" square; 1½ "–3" thick (305, 455, 610 square; 38–75 thick)

  * Interlocking pavers: 2½"–31/2" thick (64–90 thick)

  * Grid or turf block: 3 ½" thick (90 thick)

  * Granite cobble: 4" or 6" square; 6" thick (100 or 150 square; 150 thick)

  * Cut stone: width and length varies; 1"–2" thick (25–51 thick)

### **Paving Materials**

  * Consult local supplier for availability of shapes, sizes, colors, textures, absorption properties, compressive strength, and installation recommendations. 

## **1.35 PAVING**

### **Paving Patterns**

  * Unit running bond

  * Stack bond

  * Unit basketweave

  * Interlocking basketweave

  * Octagon and dot

  * Roman cobble

  * Coursed ashlar

  * Unit herringbone

  * Interlocking herringbone

  * Interlocking basketweave

  * Turf block

  * Random stone

### **Edge Conditions**

### **Flexible Base**

### **Rigid Base**

### **Paving Details**

## **1.36 THE SITE PLAN**

The site plan illustrates the existing natural and built features of a site and describes proposed construction in relation to these existing features.  Usually based on an engineer's land survey, the site plan is an essential piece of a set of construction documents.  A completed site plan should include the following items:

**1.**  Name and address of property owner

**2.**  Address of property, if different from owner's address

**3.**  Legal description of property

**4.**  Source and date of land survey

**5.**  Description of the site boundaries: dimensions of property lines, their bearing relative to north, angles of corners, and radii of curves

**6.**  Contract or project limits, if different from site boundaries

**7.**  North arrow and scale of drawing

**8.**  Location and description of bench marks that establish the reference points for the location and elevations of new construction

**9.**  Identification and dimensions of adjacent streets, alleys, and other public rights-of-way

**10.**  Location and dimensions of any easements or rights-of-way that cross the site

**11.**  Dimensions of setbacks required by the zoning ordinance

**12.**  Location and size of existing structures and a description of any demolition required by the new construction

**13.**  Location, shape, and size of structures proposed for construction, including roof overhangs and other projections

**14.**  Location and dimensions of existing and proposed paved walkways, drives, and parking areas

**15.**  Location of existing utilities: water mains, sanitary and storm sewers, gas lines, electrical power lines, telephone and cable lines, fire hydrants, as well as proposed points of connections

**16.**  Existing contour lines, new contour lines and the finish grades of drives, walks, lawns, or other improved surfaces after completion of construction or grading operations

**17.**  Existing plant materials to remain and those to be removed

**18.**  Existing water features, such as drainage swales, creeks, flood plains, watersheds, or shorelines

**19.**  Proposed landscaping features, such as fencing, retaining walls, and plantings; if extensive, landscaping and other site improvements may be shown on a separate site plan. 

**20.**  References to related drawings and details

## **1.37 THE SITE PLAN**

## **1.38 SITE DESCRIPTION**

A legal description of a site consists of the location and boundaries of a specific parcel of land, based on a metes-and-bounds survey or a rectangular system of survey, or made with reference to a recorded plat. 

  * A survey plat is a legal document describing the location, boundaries, and dimensions of a tract or parcel of land, including zoning and planning commission approvals, easements and restrictions, and, for a subdivision, the dividing lines of street, blocks, and lots, and the numbering and dimensions of each lot. 

**CSI MasterFormat 02 21 13: Site Surveys**

# **Chapter 2**  
 **THE BUILDING**

2.02 The Building

2.03 Building Systems

2.05 Building Codes

2.06 Types of Construction

2.07 Occupancy Classification

2.08 Loads on Buildings

2.09 Wind Loads

2.10 Earthquake Loads

2.11 Structural Forces

2.12 Structural Equilibrium

2.13 Columns

2.14 Beams

2.15 Beam Spans

2.16 Trusses

2.17 Frames & Walls

2.18 Plate Structures

2.19 Structural Units

2.20 Structural Spans

2.21 Structural Patterns

2.22 Lateral Stability

2.24 High-Rise Structures

2.25 Arches & Vaults

2.26 Domes

2.27 Shell Structures

2.28 Cable Structures

2.29 Membrane Structures

2.30 Joints & Connections

## **2.02 THE BUILDING**

Architecture and building construction are not necessarily one and the same thing.  An understanding of the methods for assembling various materials, elements, and components is necessary during both the design and the construction of a building.  This understanding, however, while it enables one to build architecture, does not guarantee it.  A working knowledge of building construction is only one of several critical factors in the execution of architecture.  When we speak of architecture as the art of building, we should consider the following conceptual systems of order in addition to the physical ones of construction:

  * The definition, scale, proportion, and organization of the interior spaces of a building
  * The ordering of human activities by their scale and dimension
  * The functional zoning of the spaces of a building according to purpose and use
  * Access to the horizontal and vertical paths of movement through the interior of a building
  * The sensible qualities of a building: form, space, light, color, texture, and pattern
  * The building as an integrated component within the natural and built environment

Of primary interest to us in this book are the physical systems that define, organize, and reinforce the perceptual and conceptual ordering of a building. 

A system can be defined as an assembly of interrelated or interdependent parts forming a more complex and unified whole and serving a common purpose.  A building can be understood to be the physical embodiment of a number of systems and subsystems that must necessarily be related, coordinated, and integrated with each other as well as with the three-dimensional form and spatial organization of the building as a whole. 

## **2.03 BUILDING SYSTEMS**

### **Structural System**

The structural system of a building is designed and constructed to support and transmit applied gravity and lateral loads safely to the ground without exceeding the allowable stresses in its members. 

  * The superstructure is the vertical extension of a building above the foundation. 
  * Columns, beams, and loadbearing walls support floor and roof structures. 
  * The substructure is the underlying structure forming the foundation of a building. 

### **Enclosure System**

The enclosure system is the shell or envelope of a building, consisting of the roof, exterior walls, windows, and doors. 

  * The roof and exterior walls shelter interior spaces from inclement weather and control moisture, heat, and air flow through the layering of construction assemblies. 
  * Exterior walls and roofs also dampen noise and provide security and privacy for the occupants of a building. 
  * Doors provide physical access. 
  * Windows provide access to light, air, and views. 
  * Interior walls and partitions subdivide the interior of a building into spatial units. 

### **Mechanical Systems**

The mechanical systems of a building provide essential services to a building. 

  * The water supply system provides potable water for human consumption and sanitation. 
  * The sewage disposal system removes fluid waste and organic matter from a building. 
  * Heating, ventilating, and air-conditioning systems condition the interior spaces of a building for the environmental comfort of the occupants. 
  * The electrical system controls, meters, and protects the electric power supply to a building, and distributes it in a safe manner for power, lighting, security, and communication systems. 
  * Vertical transportation systems carry people and goods from one level to another in medium- and high-rise buildings. 
  * Fire-fighting systems detect and extinguish fires. 
  * Structures may also require waste disposal and recycling systems. 

## **2.04 BUILDING SYSTEMS**

The manner in which we select, assemble, and integrate the various building systems in construction should take into account the following factors:

### **Performance Requirements**

  * Structural compatibility, integration, and safety
  * Fire resistance, prevention, and safety
  * Allowable or desirable thickness of construction assemblies
  * Control of heat and air flow through building assemblies
  * Control of migration and condensation of water vapor
  * Accommodation of building movement due to settlement, structural deflection, and expansion or contraction with changes in temperature and humidity
  * Noise reduction, sound isolation, and acoustical privacy
  * Resistance to wear, corrosion, and weathering
  * Finish, cleanliness, and maintenance requirements
  * Safety in use

### **Aesthetic Qualities**

  * Desired relationship of building to its site, adjacent properties, and neighborhood
  * Preferred qualities of form, massing, color, pattern, texture, and detail

### **Regulatory Constraints**

  * Compliance with zoning ordinances and building codes

### **Economic Considerations**

  * Initial cost comprising material, transportation, equipment, and labor costs
  * Life-cycle costs, which include not only initial cost, but also maintenance and operating costs, energy consumption, useful lifetime, demolition and replacement costs, and interest on invested money

### **Environmental Impact**

  * Conservation of energy and resources through siting and building design
  * Energy efficiency of mechanical systems
  * Use of resource-efficient and nontoxic materials
  * See 1.03–1.06

### **Construction Practices**

  * The U.S. Occupational Health and Safety Act (OSHA) regulates the design of workplaces and sets safety standards under which a building must be constructed. 

  * Safety requirements
  * Allowable tolerances and appropriate fit
  * Conformance to industry standards and assurance
  * Division of work between the shop and the field
  * Division of labor and coordination of building trades
  * Budget constraints
  * Construction equipment required
  * Erection time required
  * Provisions for inclement weather

## **2.05 BUILDING CODES**

Building codes are adopted and enforced by local government agencies to regulate the design, construction, alteration, and repair of buildings in order to protect the public safety, health, and welfare.  The codes generally establish requirements based on the type of occupancy and construction of a building, minimum standards for materials and methods of construction, and specifications for structural and fire safety.  While codes are primarily prescriptive in nature, they also contain performance criteria, stipulating how a particular component or system must function without necessarily giving the means to be employed to achieve the results.  The codes often reference standards established by the American Society for Testing and Materials (ASTM), the American National Standards Institute (ANSI), and other technical societies and trade associations, to indicate the properties desired in a material or component and the methods of testing required to substantiate the performance of products. 

### **Model Codes**

Model codes are building codes developed by national organizations of code officials, materials and life safety experts, professional societies, and trade associations for adoption by local communities as legally enforceable regulations.  If certain provisions need to be modified or added to address local requirements or concerns, a model code may be enacted by a municipality with amendments. 

### **International Building Code ®**

Since the early part of the last century, three major model codes have been developed for use in various parts of the U.S. by the Building Officials and Code Administrators International, Inc. (BOCA), the International Conference of Building Officials (ICBO), and the Southern Building Code Conference (SBCC).  In 1994, these model-code groups merged to form the International Code Council (ICC) with the goal of developing a comprehensive and coordinated set of national model codes.  In 2000, the ICC published the first edition of the International Building Code® (IBC). 

As with the model codes that preceded it, the IBC begins by defining categories of use or occupancy and setting height and area limitations in relation to the occupancy of a building and the type of construction employed, and then prescribes five types of construction according to degree of fire resistance and combustibility.  The code also contains provisions for interior finishes, fire protection systems, emergency egress, accessibility, interior environment, energy efficiency, exterior walls and roofs, structural design, building materials, elevators and conveying systems, and existing structures. 

### **Companion Codes**

The International Residential Code® (IRC) regulates the construction of detached one- and two-family dwellings and townhouses not more than three stories in height and having a separate means of egress.  The International Existing Building Code®, which regulates the alteration, repair, and renovation of existing facilities, emerged with the increasing importance of historic preservation and sustainable reuse of existing buildings.  Other companion codes include the International Energy Conservation Code®, International Fire Code®, International Mechanical Code®, and International Plumbing Code®. 

### **Other Important Codes**

The National Fire Protection Association (NFPA) has developed a new model building code, NFPA 5000, as an alternative to the International Building Code.  The NFPA also publishes other code documents. 

  * NFPA-70, the National Electric Code, ensures the safety of persons and the safeguarding of buildings and their contents from hazards arising from the use of electricity for light, heat, and power. 
  * NFPA-101, the Life Safety Code, establishes minimum requirements for fire safety, the prevention of danger from fire, smoke and gases, fire detection and alarm systems, fire extinguishing systems, and emergency egress. 
  * NFPA-13 governs the installation of fire sprinklers. 

### **Federal Requirements**

In addition to the locally adopted version of the model codes, there are specific federal requirements that must be considered in the design and construction of facilities. 

  * The Americans with Disabilities Act (ADA) of 1990 is federal civil-rights legislation requiring that buildings be made accessible to persons with physical disabilities and certain defined mental disabilities.  The ADA Accessibility Guidelines (2010 ADA Standards for Accessible Design) are maintained by the U.S. Access Board, an independent governmental agency, and the regulations are administered by the U.S. Department of Justice.  Federal facilities must comply with standards issued under the Architectural Barriers Act (ABA).  In its last update, the Access Board harmonized the ADA guidelines with its guidelines for facilities covered by the ABA and published them jointly as the ADA-ABA Accessibility Guidelines.  In addition, the Board and the International Code Council (ICC) worked cooperatively to coordinate the ADA and ABA guidelines and access provisions in the International Building Code. 
  * The Federal Fair Housing Act (FFHA) of 1988 includes Department of Housing and Urban Development (HUD) regulations requiring all residential complexes of four or more dwelling units constructed after March 13, 1991 to be adaptable for use by persons with disabilities. 

## **2.06 TYPES OF CONSTRUCTION**

The IBC classifies the construction of a building according to the fire resistance of its major elements: structural frame, exterior and interior bearing walls, nonbearing walls and partitions, and floor and roof assemblies. 

  * Type I buildings have their major building elements constructed of noncombustible materials, such as concrete, masonry, or steel.  Some combustible materials may be allowed if they are ancillary to the primary structure of the building.  Type II buildings are similar to Type I buildings except for a reduction in the required fire-resistance ratings of the major building elements. 

  * Type V buildings have structural elements and exterior and interior walls of any material permitted by the code. 
  * Type V-Protected construction requires all major building elements, except for nonbearing interior walls and partitions, to be of one-hour fire-resistive construction. 
  * Type V-Unprotected construction has no requirements for fire-resistance except for when the code requires protection of exterior walls due their proximity to a property line or to adjacent buildings on the same site. 

  * The table below outlines the required fire-resistive ratings of major building elements for the various types of construction.  Consult Table 601 of the International Building Code for more specific requirements. 
  * See Appendix for the fire-resistance ratings of representative construction assemblies. 

## **2.07 OCCUPANCY CLASSIFICATION**

The IBC limits the maximum height and area per floor of a building according to construction type and occupancy group, expressing the intrinsic relationship between degree of fire resistance, size of a building, and nature of an occupancy.  The larger a building, the greater the number of occupants, and the more hazardous the occupancy, the more fire-resistant the facility should be.  The intent is to protect a building from fire and to contain a fire long enough for the safe evacuation of occupants and for a firefighting response to occur.  The limitation on size may be exceeded if the building is equipped with an automatic fire sprinkler system, or if it is divided by fire walls into areas not exceeding the size limitation. 

### **Examples of Occupancy Classifications**

**A Assembly**

Auditoriums, theaters, and stadiums

**B Business**

Offices, laboratories, and higher education facilities

**E Educational**

Child-care facilities and schools through the 12th grade

**F Factories**

Fabricating, assembling, or manufacturing facilities

**H Hazardous uses**

Facilities handling a certain nature and quantity of hazardous materials

**I Institutional**

Facilities for supervised occupants, such as hospitals, nursing homes, and reformatories

**M Mercantile**

Stores for the display and sale of merchandise

**R Residential**

Homes, apartment buildings, and hotels

**S Storage**

Warehousing facilities

## **2.08 LOADS ON BUILDINGS**

In enclosing space for habitation, the structural system of a building must be able to support two types of loads—static and dynamic. 

### **Static Loads**

Static loads are assumed to be applied slowly to a structure until it reaches its peak value without fluctuating rapidly in magnitude or position.  Under a static load, a structure responds slowly and its deformation reaches a peak when the static force is maximum. 

  * Live loads comprise any moving or movable loads on a structure resulting from occupancy, collected snow and water, or moving equipment.  A live load typically acts vertically downward but may act horizontally as well to reflect the dynamic nature of a moving load. 

### **Dynamic Loads**

Dynamic loads are applied suddenly to a structure, often with rapid changes in magnitude and point of application.  Under a dynamic load, a structure develops inertial forces in relation to its mass and its maximum deformation does not necessarily correspond to the maximum magnitude of the applied force.  The two major types of dynamic loads are wind loads and earthquake loads. 

## **2.09 WIND LOADS**

Wind loads are the forces exerted by the kinetic energy of a moving mass of air, assumed to come from any horizontal direction. 

  * The structure, components, and cladding of a building must be designed to resist wind-induced sliding, uplift, or overturning. 

  * Total wind loads are determined by taking the product of the wind load per square foot multiplied by the area of building or structure projected on a vertical plane normal to the wind direction. 
  * Wind is to be assumed to come from any horizontal direction and wind pressures are to be assumed to act normal to the surface considered. 

  * Because wind can create positive pressure as well as suction or negative pressure on a building, the force is to be resisted in either direction normal to the surface. 

  * Design wind pressure is a minimum design value for the equivalent static pressure on the exterior surfaces of a structure resulting from a critical wind velocity, equal to a reference wind pressure measured at a height of 33′ (10 m), modified by a number of coefficients to account for the effects of exposure condition, building height, wind gusts, and the geometry and orientation of the structure to the impinging air flow. 
  * An importance factor may increase the design values for wind or seismic forces on a building because of its large occupancy, its potentially hazardous contents, or its essential nature in the wake of a hurricane or earthquake. 

## **2.10 EARTHQUAKE LOADS**

An earthquake consists of a series of longitudinal and transverse vibrations induced in the earth's crust by the abrupt movement of plates along fault lines.  The shocks of an earthquake propagate along the earth's surface in the form of waves and attenuate logarithmically with distance from its source.  While these ground motions are three-dimensional in nature, their horizontal components are considered to be the more critical in structural design; the vertical load-carrying elements of a structure usually have considerable reserve for resisting additional vertical loads. 

  * A more complex dynamic analysis is required for high-rise structures, structures with irregular shapes or framing systems, or for structures built on soft or plastic soils susceptible to failure or collapse under seismic loading. 

The following is a brief introduction to the way a structural system must resolve all of the forces acting on a building and channel them to the ground.  For more complete information on the structural design and analysis of buildings, see Bibliography. 

## **2.11 STRUCTURAL FORCES**

A force is any influence that produces a change in the shape or movement of a body.  It is considered to be a vector quantity possessing both magnitude and direction, represented by an arrow whose length is proportional to the magnitude and whose orientation in space represents the direction.  A single force acting on a rigid body may be regarded as acting anywhere along its line of action without altering the external effect of the force.  Two or more forces may be related in the following ways:

  * Collinear forces occur along a straight line, the vector sum of which is the algebraic sum of the magnitudes of the forces, acting along the same line of action. 

  * In a similar manner, any single force can be resolved into two or more concurrent forces having a net effect on a rigid body equivalent to that of the initial force.  For convenience in structural analysis, these are usually the rectangular or Cartesian components of the initial force. 

  * Nonconcurrent forces have lines of action that do not intersect at a common point, the vector sum of which is a single force that would cause the same translation and rotation of a body as the set of original forces. 

## **2.12 STRUCTURAL EQUILIBRIUM**

In both structural design and analysis, we are concerned first with the magnitude, direction, and point of application of forces, and their resolution to produce a state of equilibrium.  Equilibrium is a state of balance or rest resulting from the equal action of opposing forces.  In other words, as each structural element is loaded, its supporting elements must react with equal but opposite forces.  For a rigid body to be in equilibrium, two conditions are necessary. 

  * First, the vector sum of all forces acting on it must equal zero, ensuring translational equilibrium: ∑Fx = 0; ∑Fy = 0; ∑Fz = 0. 
  * Second, the algebraic sum of all moments of the forces about any point or line must equal zero, ensuring rotational equilibrium: ∑M = 0. 

  * Newton's third law of motion, the law of action and reaction, states that for every force acting on a body, the body exerts a force having equal magnitude in the opposite direction along the same line of action as the original force. 

## **2.13 COLUMNS**

Columns are rigid, relatively slender structural members designed primarily to support axial compressive loads applied to the ends of the members.  Relatively short, thick columns are subject to failure by crushing rather than by buckling.  Failure occurs when the direct stress from an axial load exceeds the compressive strength of the material available in the cross section.  An eccentric load, however, can produce bending and result in an uneven stress distribution in the section. 

Long, slender columns are subject to failure by buckling rather than by crushing.  Buckling is the sudden lateral or torsional instability of a slender structural member induced by the action of an axial load before the yield stress of the material is reached.  Under a buckling load, a column begins to deflect laterally and cannot generate the internal forces necessary to restore its original linear condition.  Any additional loading would cause the column to deflect further until collapse occurs in bending.  The higher the slenderness ratio of a column, the lower is the critical stress that will cause it to buckle.  A primary objective in the design of a column is to reduce its slenderness ratio by shortening its effective length or maximizing the radius of gyration of its cross section. 

## **2.14 BEAMS**

Beams are rigid structural members designed to carry and transfer transverse loads across space to supporting elements.  The nonconcurrent pattern of forces subjects a beam to bending and deflection, which must be resisted by the internal strength of the material. 

  * Moment of inertia is the sum of the products of each element of an area and the square of its distance from a coplanar axis of rotation.  It is a geometric property that indicates how the cross-sectional area of a structural member is distributed and does not reflect the intrinsic physical properties of a material. 
  * Section modulus is a geometric property of a cross section, defined as the moment of inertia of the section divided by the distance from the neutral axis to the most remote surface. 

## **2.15 BEAM SPANS**

  * A cantilever is a projecting beam or other rigid structural member supported at only one fixed end. 

## **2.16 TRUSSES**

A truss is a structural frame based on the geometric rigidity of the triangle and composed of linear members subject only to axial tension or compression. 

  * Panel point is any of the joints between a principal web member and a chord.  A truss must be loaded only at its panel points if its members are to be subject only to axial tension or compression.  To prevent secondary stresses from developing, the centroidal axes of truss members and the load at a joint should pass through a common point. 

  * See 6.09 for types of trusses and truss configurations. 

  * Vierendeel trusses are framed beam structures having vertical web members rigidly connected to parallel top and bottom chords.  Vierendeel trusses are not true trusses because their members are subject to nonaxial bending forces. 

## **2.17 FRAMES & WALLS**

A beam simply supported by two columns is not capable of resisting lateral forces unless it is braced.  If the joints connecting the columns and beam are capable of resisting both forces and moments, then the assembly becomes a rigid frame.  Applied loads produce axial, bending, and shear forces in all members of the frame because the rigid joints restrain the ends of the members from rotating freely.  In addition, vertical loads cause a rigid frame to develop horizontal thrusts at its base.  A rigid frame is statically indeterminate and rigid only in its plane. 

  * A fixed frame is a rigid frame connected to its supports with fixed joints.  A fixed frame is more resistant to deflection than a hinged frame but also more sensitive to support settlements and thermal expansion and contraction. 

  * A hinged frame is a rigid frame connected to its supports with pin joints.  The pin joints prevent high bending stresses from developing by allowing the frame to rotate as a unit when strained by support settlements, and to flex slightly when stressed by changes in temperature. 

  * A three-hinged frame is a structural assembly of two rigid sections connected to each other and to its supports with pin joints.  While more sensitive to deflection than either the fixed or hinged frame, the three-hinged frame is least affected by support settlements and thermal stresses.  The three pin joints also permit the frame to be analyzed as a statically determinate structure. 

If we fill in the plane defined by two columns and a beam, it becomes a loadbearing wall that acts as a long, thin column in transmitting compressive forces to the ground.  Loadbearing walls are most effective when carrying coplanar, uniformly distributed loads and most vulnerable to forces perpendicular to their planes.  For lateral stability, loadbearing walls must rely on buttressing with pilasters, cross walls, transverse rigid frames, or horizontal slabs. 

Any opening in a loadbearing wall weakens its structural integrity.  A lintel or arch must support the load above a door or window opening and allow the compressive stresses to flow around the opening to adjacent sections of the wall. 

## **2.18 PLATE STRUCTURES**

Plate structures are rigid, planar, usually monolithic structures that disperse applied loads in a multidirectional pattern, with the loads generally following the shortest and stiffest routes to the supports.  A common example of a plate structure is a reinforced concrete slab. 

## **2.19 STRUCTURAL UNITS**

With the principal structural elements of column, beam, slab, and loadbearing wall, it is possible to form an elementary structural unit capable of defining and enclosing a volume of space for habitation.  This structural unit is the basic building block for the structural system and spatial organization of a building. 

  * Horizontal spans may be traversed by reinforced concrete slabs or by a layered, hierarchical arrangement of girders, beams, and joists supporting planks or decking. 
  * The vertical support for a structural unit may be provided by loadbearing walls or by a framework of columns and beams. 

The dimensions and proportions of a structural unit or bay influence the selection of an appropriate spanning system. 

  * One-way systems of joists, planks, or slabs are more efficient when structural bays are rectangular—that is, when the ratio of the long to the short dimensions is greater than 1.5:1—or when the structural grid generates a linear pattern of spaces. 

  * Two-way systems of beams and slabs are more effective for square or nearly square bays. 

  * A two-way slab supported by four columns defines a horizontal layer of space. 

  * The parallel nature of loadbearing walls leads naturally to the use of one-way spanning systems. 
  * Because loadbearing walls are most effective when supporting a uniformly distributed load, they typically support a series of joists, planks, or a one-way slab. 

  * A linear framework of columns and beams defines a three-dimensional module of space capable of being expanded both horizontally and vertically. 

  * Two loadbearing walls naturally define an axial, bidirectional space.  Secondary axes can be developed perpendicular to the primary axis with openings within the loadbearing walls. 

## **2.20 STRUCTURAL SPANS**

The spanning capability of horizontal elements determines the spacing of their vertical supports.  This fundamental relationship between the span and spacing of structural elements influences the dimensions and scale of the spaces defined by the structural system of a building.  The dimensions and proportions of structural bays, in turn, should be related to the programmatic requirements of the spaces. 

## **2.21 STRUCTURAL PATTERNS**

The arrangement of principal vertical supports not only regulates the selection of a spanning system, it also establishes the possibilities for the ordering of spaces and functions in a building. 

The principal points and lines of support for a structural system typically define a grid.  The critical points of the grid are those at which columns and loadbearing walls collect loads from beams and other horizontal spanning elements and channel these loads vertically to the ground foundation. 

The inherent geometric order of a grid can be used in the design process to initiate and reinforce the functional and spatial organization of a building design. 

## **2.22 LATERAL STABILITY**

The structural elements of a building must be sized, configured, and joined to form a stable structure under any possible load conditions.  Therefore, a structural system must be designed to not only carry vertical gravity loads, but also withstand lateral wind and seismic forces from any direction.  The following are the basic mechanisms for ensuring lateral stability. 

  * Knee bracing

  * K-brace

  * Cross bracing

Any of these systems may be used singly or in combination to stabilize a structure.  Of the three vertical systems, a rigid frame tends to be the least efficient.  However, rigid frames can be useful when employing braced frames or shear walls would form undesired barriers between adjacent spaces. 

## **2.23 LATERAL STABILITY**

To avoid destructive torsional effects, structures subject to lateral forces should be arranged and braced symmetrically with centers of mass and resistance as coincident as possible.  The asymmetrical layout of irregular structures generally requires dynamic analysis in order to determine the torsional effects of lateral forces. 

Irregular structures are characterized by any of various plan or vertical irregularities, such as the asymmetrical layout of mass or lateral force–resisting elements, a soft or weak story, or a discontinuous shear wall or diaphragm. 

  * A reentrant corner is a plan configuration of a structure having projections beyond a corner significantly greater than the plan dimension in the given direction.  A re-entrant corner tends to produce differential motions between different portions of the structure, resulting in local stress concentrations at the corner.  Solutions include providing a seismic joint to separate the building into simpler shapes, tying the building together more strongly at the corner, or splaying the corner. 

  * Seismic joints physically separate adjacent building masses so that free vibratory movement in each can occur independently of the other. 

  * A discontinuous diaphragm is a horizontal diaphragm having a large cutout or open area, or a stiffness significantly less than that of the story above or below. 

  * A discontinuous shear wall has a large offset or a significant change in horizontal dimension. 

  * A soft or weak story has lateral stiffness or strength significantly less than that of the stories above. 

**CSI MasterFormat 13 48 00: Sound, Vibration, and Seismic Control**

## **2.24 HIGH-RISE STRUCTURES**

Tall buildings are particularly susceptible to the effects of lateral forces.  A rigid frame is the least efficient way to achieve lateral stability and is appropriate only for low- to medium-rise structures.  As the height of a building increases, it becomes necessary to supplement a rigid frame with additional bracing mechanisms, such as diagonal bracing or a rigid core.  An efficient type of high-rise structure is a tube structure that has perimeter lateral force–resisting systems internally braced by rigid floor diaphragms.  The structure acts essentially as a cantilevered box beam in resisting lateral forces. 

  * A framed tube has closely spaced perimeter columns rigidly connected by deep spandrel beams. 

  * A perforated shell tube has perimeter shear walls with less than 30% of the surface area perforated by openings. 

  * A braced tube is a framed structure tied together by a system of diagonal braces. 

  * A trussed tube has trussed wall frames of widely spaced columns tied together by diagonal or cross bracing. 

  * A latticed truss tube has perimeter frames of closely spaced diagonals with no vertical columns. 

  * Bundled tubes is an assembly of narrow tubes tied directly to each other to form a modular structure that behaves like a multicellular box girder cantilevering out of the ground.  More tubes are sometimes provided in the lower portion of a tall structure where greater lateral force resistance is needed. 

  * A tube-in-tube structure has an inner braced core added to the perimeter tube to improve its shear stiffness in resisting lateral forces. 

Damping mechanisms are viscoelastic devices that are typically installed at structural joints to absorb the energy generated by wind or earthquake forces, progressively diminish or eliminate vibratory or oscillatory motions, and prevent destructive resonances from occurring. 

  * Internal damping is the damping that naturally occurs as a building undergoes elastic or plastic deformation, as from the internal friction of a stressed material (hysteresis damping), from the friction between two moving parts (frictional damping), or from the viscous resistance of a fluid such as silicone oil (viscous damping). 

## **2.25 ARCHES & VAULTS**

Columns, beams, slabs, and bearing walls are the most common structural elements because of the rectilinear building geometry they are capable of generating.  There are, however, other means of spanning and enclosing space.  These are generally form-active elements that, through their shape and geometry, make efficient use of their material for the distances spanned.  While beyond the scope of this book, they are briefly described in the following section. 

Arches are curved structures for spanning an opening, designed to support a vertical load primarily by axial compression.  They transform the vertical forces of a supported load into inclined components and transmit them to abutments on either side of the archway. 

  * Masonry arches are constructed of individual wedge-shaped stone or brick voussoirs; for more information on masonry arches, see 5.20. 
  * Rigid arches consist of curved, rigid structures of timber, steel, or reinforced concrete capable of carrying some bending stresses. 

Vaults are arched structures of stone, brick, or reinforced concrete, forming a ceiling or roof over a hall, room, or other wholly or partially enclosed space.  Because a vault behaves as an arch extended in a third dimension, the longitudinal supporting walls must be buttressed to counteract the outward thrusts of the arching action. 

## **2.26 DOMES**

A dome is a spherical surface structure having a circular plan and constructed of stacked blocks, a continuous rigid material like reinforced concrete, or of short, linear elements, as in the case of a geodesic dome.  A dome is similar to a rotated arch except that circumferential forces are developed that are compressive near the crown and tensile in the lower portion. 

  * Schwedler domes are steel dome structures having members that follow the lines of latitude and longitude, and a third set of diagonals completing the triangulation. 

  * Lattice domes are steel dome structures having members that follow the circles of latitude, and two sets of diagonals forming a series of isosceles triangles. 

  * Geodesic domes are steel dome structures having members that follow three principal sets of great circles intersecting at 60°, subdividing the dome surface into a series of equilateral spherical triangles. 

**CSI MasterFormat 13 33 00: Geodesic Structures**

## **2.27 SHELL STRUCTURES**

Shells are thin, curved plate structures typically constructed of reinforced concrete.  They are shaped to transmit applied forces by membrane stresses—the compressive, tensile, and shear stresses acting in the plane of their surfaces.  A shell can sustain relatively large forces if uniformly applied.  Because of its thinness, however, a shell has little bending resistance and is unsuitable for concentrated loads. 

  * Barrel shells are cylindrical shell structures.  If the length of a barrel shell is three or more times its transverse span, it behaves as a deep beam with a curved section spanning in the longitudinal direction.  If it is relatively short, it exhibits archlike action.  Tie rods or transverse rigid frames are required to counteract the outward thrusts of the arching action. 

  * Rotational surfaces are generated by rotating a plane curve about an axis.  Spherical, elliptical, and parabolic dome surfaces are examples of rotational surfaces. 

## **2.28 CABLE STRUCTURES**

Cable structures utilize the cable as the principal means of support.  Because cables have high tensile strength but offer no resistance to compression or bending, they must be used purely in tension.  When subject to concentrated loads, the shape of a cable consists of straight-line segments.  Under a uniformly distributed load, it will take on the shape of an inverted arch. 

Suspension structures utilize a network of cables suspended and prestressed between compression members to directly support applied loads. 

  * Cable-stayed structures have vertical or inclined masts from which cables extend to support horizontally spanning members arranged in a parallel or radial pattern. 

**CSI MasterFormat 13 31 23: Tensioned Fabric Structures**

## **2.29 MEMBRANE STRUCTURES**

Membranes are thin, flexible surfaces that carry loads primarily through the development of tensile stresses.  They may be suspended or stretched between posts, or be supported by air pressure. 

Tent structures are membrane structures that are prestressed by externally applied forces and held completely taut under all anticipated load conditions.  To avoid extremely high tensile forces, membrane structures should have relatively sharp curvatures in opposite directions. 

Pneumatic structures are membrane structures that are placed in tension and stabilized against wind and snow loads by the pressure of compressed air.  The membrane is usually a woven textile or glass-fiber fabric coated with a synthetic material such as silicone.  Translucent membranes provide natural illumination, gather solar radiation in the winter, and cool the interior space at night.  Reflective membranes reduce solar heat gain.  A fabric liner can capture air space to improve the thermal resistance of the structure. 

There are two kinds of pneumatic structures: air-supported structures and air-inflated structures. 

  * Air-supported structures consist of a single membrane supported by an internal air pressure slightly higher than normal atmospheric pressure, and securely anchored and sealed along the perimeter to prevent leaking.  Air locks are required at entrances to maintain the internal air pressure. 

  * Air-inflated structures are supported by pressurized air within inflated building elements.  These elements are shaped to carry loads in a traditional manner, while the enclosed volume of building air remains at normal atmospheric pressure.  The tendency for a double-membrane structure to bulge in the middle is restrained by a compression ring or by internal ties or diaphragms. 

**CSI MasterFormat 13 31 13: Air-Supported Fabric Structures**

## **2.30 JOINTS & CONNECTIONS**

The manner in which forces are transferred from one structural element to the next and how a structural system performs as a whole depend to a great extent on the types of joints and connections used.  Structural elements can be joined to each other in three ways.  Butt joints allow one of the elements to be continuous and usually require a third mediating element to make the connection.  Overlapping joints allow all of the connected elements to bypass each other and be continuous across the joint.  The joining elements can also be molded or shaped to form a structural connection. 

The connectors used to join the structural elements may be in the form of a point, a line, or a surface.  While linear and surface types of connectors resist rotation, point connectors do not unless a series of them is distributed across a large surface area. 

  * A cable anchorage allows rotation but resists translation only in the direction of the cable. 

# **Chapter 3**  
 **FOUNDATION SYSTEMS**

3.02 Foundation Systems

3.04 Types of Foundation Systems

3.06 Underpinning

3.07 Excavation Support Systems

3.08 Shallow Foundations

3.09 Spread Footings

3.10 Foundation Walls

3.16 Column Footings

3.17 Foundations on Sloping Ground

3.18 Concrete Slabs on Grade

3.22 Pole Foundations

3.24 Deep Foundations

3.25 Pile Foundations

3.26 Caisson Foundations

## **3.02 FOUNDATION SYSTEMS**

The foundation is the lowest division of a building—its substructure—constructed partly or wholly below the surface of the ground.  Its primary function is to support and anchor the superstructure above and transmit its loads safely into the earth.  Because it serves as a critical link in the distribution and resolution of building loads, the foundation system must be designed to both accommodate the form and layout of the superstructure above and respond to the varying conditions of soil, rock, and water below. 

The principal loads on a foundation are the combination of dead and live loads acting vertically on the superstructure.  In addition, a foundation system must anchor the superstructure against wind-induced sliding, overturning, and uplift, withstand the sudden ground movements of an earthquake, and resist the pressure imposed by the surrounding soil mass and groundwater on basement walls.  In some cases, a foundation system may also have to counter the thrust from arched or tensile structures. 

## **3.03 FOUNDATION SYSTEMS**

Settlement is the gradual subsiding of a structure as the soil beneath its foundation consolidates under loading.  As a building is constructed, some settlement is to be expected as the load on the foundation increases and causes a reduction in the volume of soil voids containing air or water.  This consolidation is usually slight and occurs rather quickly as loads are applied on dense, granular soils, such as coarse sand and gravel.  When the foundation soil is a moist, cohesive clay, which has a scale-like structure and a relatively large percentage of voids, consolidation can be quite large and occur slowly over a longer period of time. 

A properly designed and constructed foundation system should distribute its loads so that whatever settlement occurs is minimal or is uniformly distributed under all portions of the structure.  This is accomplished by laying out and proportioning the foundation supports so that they transmit an equal load per unit area to the supporting soil or rock without exceeding its bearing capacity. 

Differential settlement—the relative movement of different parts of a structure caused by uneven consolidation of the foundation soil—can cause a building to shift out of plumb and cracks to occur in its foundation, structure, or finishes.  If extreme, differential settlement can result in the failure of the structural integrity of a building. 

## **3.04 TYPES OF FOUNDATION SYSTEMS**

Foundations utilize a combination of bearing walls, columns, and piers to transmit building loads directly to the earth.  These structural elements can form various types of substructures:

## **3.05 TYPES OF FOUNDATION SYSTEMS**

We can classify foundation systems into two broad categories—shallow foundations and deep foundations. 

Factors to consider in selecting and designing the type of foundation system for a building include:

  * Pattern and magnitude of building loads
  * Subsurface and groundwater conditions
  * Topography of the site
  * Impact on adjacent properties
  * Building code requirements
  * Construction method and risk

The design of a foundation system requires professional analysis and design by a qualified structural engineer.  When designing anything other than a single-family dwelling on stable soil, it is also advisable to have a geotechnical engineer undertake a subsurface investigation in order to determine the type and size of foundation system required for the building design. 

## **3.06 UNDERPINNING**

Underpinning refers to the process of rebuilding or strengthening the foundation of an existing building, or extending it when a new excavation in adjoining property is deeper than the existing foundation. 

  * To provide temporary support while an existing foundation is repaired, strengthened, or deepened, needle beams are passed through the foundation wall and carried by hydraulic jacks and shores. 

  * Another method for providing temporary support is to dig intermittent pits under the existing foundation down to the level of the new footings.  After the new foundation wall and footing sections are placed, additional pits are dug until the entire wall has been deepened. 

  * An alternative to extending a new foundation wall and placing new footings is to construct piles or caissons on either side of the existing foundation, remove a section of foundation wall, and replace the section with a reinforced concrete pile cap. 

**CSI MasterFormat 31 40 00: Shoring and Underpinning**

## **3.07 EXCAVATION SUPPORT SYSTEMS**

When the building site is sufficiently large that the sides of an excavation can be bench terraced or sloped at an angle less than the angle of repose for the soil, no supporting structure is necessary.  When the sides of a deep excavation exceed the angle of repose for the soil, however, the earth must be temporarily braced or shored until the permanent construction is in place. 

  * A slurry wall (CSI: 31 56 00) is a concrete wall cast in a trench to serve as sheeting and often as a permanent foundation wall.  It is constructed by excavating a trench in short lengths, filling it with a slurry of bentonite and water to prevent the sidewalls from collapsing, setting reinforcement, and placing concrete in the trench with a tremie to displace the slurry. 

  * Dewatering (CSI: 31 23 19) refers to the process of lowering a water table or preventing an excavation from filling with groundwater.  It is accomplished by driving perforated tubes called wellpoints into the ground to collect water from the surrounding area so it can be pumped away. 

**CSI MasterFormat 31 50 00: Excavation Support and Protection**

## **3.08 SHALLOW FOUNDATIONS**

The lowest part of a shallow foundation are spread footings.  They are extended laterally to distribute their load over an area of soil wide enough that the allowable bearing capacity of the soil is not exceeded.  The contact area required is equal to the quotient of the magnitude of forces transmitted and the allowable bearing capacity of the supporting soil mass. 

When footings for light frame construction bear on stable, noncohesive soil and transmit a continuous load of less than 2,000 pounds per lineal foot (29 kN/m), they may have the following cross-sectional proportions. 

To minimize the effects of ground heaving when groundwater freezes and expands in cold weather, building codes require that footings be placed below the depth of frost penetration expected at the building site. 

## **3.09 SPREAD FOOTINGS**

The most common forms of spread footings are strip footings and isolated footings. 

  * Strip footings are the continuous spread footings of foundation walls. 

  * Isolated footings are the individual spread footings supporting freestanding columns and piers. 

Other types of spread footings include the following:

  * Stepped footings are strip footings that change levels in stages to accommodate a sloping grade and maintain the required depth at all points around a building. 

  * A continuous footing is a reinforced concrete footing extended to support a row of columns. 

  * A grade beam is a reinforced concrete beam supporting a bearing wall at or near ground level and transferring the load to isolated footings, piers, or piles. 

  * A cantilever or strap footing consists of a column footing connected by a tie beam to another footing in order to balance an asymmetrically imposed load. 

  * A combined footing is a reinforced concrete footing for a perimeter foundation wall or column extended to support an interior column load. 

  * Cantilever and combined footings are often used when a foundation abuts a property line and it is not possible to construct a symmetrically loaded footing.  To prevent the rotation or differential settlement that an asymmetrical loading condition can produce, continuous and cantilever footings are proportioned to generate uniform soil pressure. 

  * A floating foundation, used in yielding soil, has for its footing a mat placed deep enough that the weight of the excavated soil is equal to or greater than the weight of the construction being supported. 

**CSI MasterFormat 03 30 00: Cast-in-Place Concrete**

## **3.10 FOUNDATION WALLS**

Foundation walls provide support for the superstructure above and enclose a basement or crawl space partly or wholly below grade.  In addition to the vertical loads from the superstructure, foundation walls must be designed and constructed to resist active earth pressure and anchor the superstructure against wind and seismic forces. 

## **3.11 FOUNDATION WALLS**

Crawl spaces enclosed by a continuous foundation wall or piers provide space under a first floor for the integration of and access to mechanical, electrical, and plumbing installations. 

## **3.12 FOUNDATION WALLS**

### **Concrete Foundation Walls**

Cast-in-place concrete foundation walls require formwork and access to place the concrete. 

## **3.13 FOUNDATION WALLS**

The top of a foundation wall must be prepared to receive, support, and anchor the wall and floor systems of the superstructure. 

### **Wood Joists**

### **Wood Beams**

### **Open-Web Steel Joists**

## **3.14 FOUNDATION WALLS**

Dampproofing is applied to a foundation wall when subsoil conditions indicate that hydrostatic pressure from the groundwater table will not occur.  When subject to hydrostatic pressure from the groundwater table, foundation walls should be waterproofed.  Some building codes require that all foundation walls enclosing a habitable space below grade be waterproofed. 

A subsoil drainage system is required to collect and divert water away from a foundation to a storm sewer, dry well, or natural outfall at a lower elevation on the site. 

## **3.15 FOUNDATION WALLS**

Treated wood foundation systems can be used for both basement and crawl space construction.  The wall sections may be built on-site or be factory-fabricated to reduce erection time.  All wood and plywood used to fabricate a foundation system must be pressure-treated with a preservative approved for ground contact use; all field cuts should be treated with the same preservative.  All metal fasteners should be of stainless steel or hot-dipped zinc-coated steel. 

**CSI MasterFormat 06 14 00: Treated Wood Foundations**

## **3.16 COLUMN FOOTINGS**

### **Reinforced Concrete Column**

### **Wood Post**

### **Steel Column**

**CSI MasterFormat 03 30 00: Cast-in-Place Concrete  
CSI MasterFormat 03 31 00: Structural Concrete**

## **3.17 FOUNDATIONS ON SLOPING GROUND**

Structures and foundations on or adjacent to ground slopes exceeding 100% should adhere to the following requirements:

Closely spaced footings or adjacent footings located at different levels can cause overlapping soil stresses. 

Stepped footings change levels in stages to accommodate a sloping grade and maintain the required depth at all points around a building. 

## **3.18 CONCRETE SLABS ON GRADE**

A concrete slab may be placed at or near grade level to serve as a combined floor and foundation system.  The suitability of a concrete slab for such use depends on the geographic location, topography, and soil characteristics of the site, and the design of the superstructure. 

Concrete slabs on grade require the support of a level, stable, uniformly dense or properly compacted soil base containing no organic matter.  When placed over soil of low bearing capacity or over highly compressible or expansive soils, a concrete ground slab must be designed as a mat or raft foundation, which requires professional analysis and design by a qualified structural engineer. 

## **3.19 CONCRETE SLABS ON GRADE**

Three types of joints may be created or constructed in order to accommodate movement in the plane of a concrete slab on grade—isolation joints, construction joints, and control joints. 

## **3.20 CONCRETE SLABS ON GRADE**

### **Masonry Wall**

### **Stud Wall**

### **Thickened Edge Slab**

## **3.21 CONCRETE SLABS ON GRADE**

**Heating Ducts**

**Embedded Heating Pipes**

**Pipe Penetrations**

**Slab Steps**

**Slab Openings**

## **3.22 POLE FOUNDATIONS**

Pole foundations elevate timber structures above the ground plane, require minimal excavation, and preserve the natural features and existing drainage patterns of a site.  They are particularly useful when building on steep slopes and in areas subject to periodic flooding. 

The treated poles are usually laid out along a grid defined by the beam-and-joist framing pattern.  Their spacing determines both the beam-and-joist spans and the vertical loads they must support. 

Poles are set in holes dug by hand or by a power auger.  Adequate embedment length, suitable backfilling, and proper connections are required for a pole structure to develop the necessary rigidity and resistance to lateral wind and seismic forces.  The required embedment length varies according to:

  * Slope of the site
  * Subsurface soil conditions
  * Pole spacing
  * Unsupported height of the poles
  * Seismic zone

## **3.23 POLE FOUNDATIONS**

Spaced beams are through-bolted to the sides of the treated poles, which then continue up to form the loadbearing frame for the superstructure. 

Poles may distribute their loads with a concrete footing or necklace or by bearing directly on rock.  Concrete pads and collars increase the contact area of the poles with the soil and distribute their loads over a larger area. 

## **3.24 DEEP FOUNDATIONS**

Deep foundations extend down through unsuitable or unstable soil to transfer building loads to a more appropriate bearing stratum of rock or dense sands and gravels well below the superstructure.  The two principal types of deep foundations are pile foundations and caisson foundations. 

A pile foundation is a system of end-bearing or friction piles, pile caps, and tie beams for transferring building loads down to a suitable bearing stratum. 

## **3.25 PILE FOUNDATIONS**

  * Timber piles are logs driven usually as a friction pile.  They are often fitted with a steel shoe and a drive band to prevent their shafts from splitting or shattering. 

  * Composite piles are constructed of two materials, such as a timber pile having a concrete upper section to prevent the portion of the pile above the water table from deteriorating. 

  * H-piles are steel H-sections, sometimes encased in concrete to a point below the water table to prevent corrosion.  H-sections can be welded together in the driving process to form any length of pile. 

  * Pipe piles are heavy steel pipes driven with the lower end either open or closed by a heavy steel plate or point and filled with concrete.  An open-ended pipe pile requires inspection and excavation before being filled with concrete. 

  * Precast concrete piles have round, square, or polygonal cross sections and sometimes an open core.  Precast piles are often prestressed. 

  * Cast-in-place concrete piles are constructed by placing concrete into a shaft in the ground.  The concrete piles may be cased or uncased. 

**CSI MasterFormat 31 62 00: Driven Piles  
CSI MasterFormat 31 63 00: Bored Piles **

## **3.26 CAISSON FOUNDATIONS**

Caissons are cast-in-place, plain or reinforced concrete piers formed by boring with a large auger or excavating by hand a shaft in the earth to a suitable bearing stratum and filling the shaft with concrete.  For this reason, they are also referred to as drilled piles or piers. 

**CSI MasterFormat 31 64 00: Caissons**

# **Chapter 4**  
 **FLOOR SYSTEMS**

4.02 Floor Systems

4.04 Concrete Beams

4.05 Concrete Slabs

4.08 Prestressed Concrete

4.10 Concrete Formwork & Shoring

4.11 Precast Concrete Floor Systems

4.12 Precast Concrete Units

4.13 Precast Concrete Connections

4.14 Structural Steel Framing

4.16 Steel Beams

4.17 Steel Beam Connections

4.19 Open-Web Steel Joists

4.20 Open-Web Joist Framing

4.22 Metal Decking

4.23 Light-Gauge Steel Joists

4.24 Light-Gauge Joist Framing

4.26 Wood Joists

4.28 Wood Joist Framing

4.32 Wood Subflooring

4.33 Prefabricated Joists & Trusses

4.35 Wood Beams

4.36 Wood Beam Supports

4.37 Wood Post-Beam Connections

4.38 Wood Plank-and-Beam Framing

4.40 Wood Decking

## **4.02 FLOOR SYSTEMS**

Floor systems are the horizontal planes that must support both live loads—people, furnishings, and movable equipment—and dead loads—the weight of the floor construction itself.  Floor systems must transfer their loads horizontally across space to either beams and columns or to loadbearing walls.  Rigid floor planes can also be designed to serve as horizontal diaphragms that act as thin, wide beams in transferring lateral forces to shear walls. 

A floor system may be composed of a series of linear beams and joists overlaid with a plane of sheathing or decking, or consist of a nearly homogeneous slab of reinforced concrete.  The depth of a floor system is directly related to the size and proportion of the structural bays it must span and the strength of the materials used.  The size and placement of any cantilevers and openings within the floor plane should also be considered in the layout of the structural supports for the floor.  The edge conditions of the floor structure and its connection to supporting foundation and wall systems affect both the structural integrity of a building and its physical appearance. 

Because it must safely support moving loads, a floor system should be relatively stiff while maintaining its elasticity.  Due to the detrimental effects that excessive deflection and vibration would have on finish flooring and ceiling materials, as well as concern for human comfort, deflection rather than bending becomes the critical controlling factor. 

The depth of the floor construction and the cavities within it should be considered if it is necessary to accommodate runs of mechanical or electrical lines within the floor system.  For floor systems between habitable spaces stacked one above another, additional factors to consider are the blockage of both airborne and structure-borne sound and the fire-resistance rating of the assembly. 

Except for exterior decks, floor systems are not normally exposed to weather.  Because they all must support traffic, however, durability, resistance to wear, and maintenance requirements are factors to consider in the selection of a floor finish and the system required to support it. 

## **4.03 FLOOR SYSTEMS**

### **Concrete**

  * Cast-in-place concrete floor slabs are classified according to their span and cast form; see 4.05–4.07. 
  * Precast concrete planks may be supported by beams or loadbearing walls. 

### **Steel**

  * Steel beams support steel decking or precast concrete planks. 
  * Beams may be supported by girders, columns, or loadbearing walls. 
  * Beam framing is typically an integral part of a steel skeleton frame system. 

  * Closely spaced light-gauge or open-web joists may be supported by beams or loadbearing walls. 
  * Steel decking or wood planks have relatively short spans. 
  * Joists have limited overhang potential. 

### **Wood**

  * Wood beams support structural planking or decking. 
  * Beams may be supported by girders, posts, or loadbearing walls. 
  * Concentrated loads and floor openings may require additional framing. 
  * Underside of floor structure may be left exposed; an applied ceiling is optional. 

  * Relatively small, closely spaced joists may be supported by beams or loadbearing walls. 
  * Subflooring, underlayment, and applied ceiling finishes have relatively short spans. 
  * Joist framing is flexible in shape and form. 

## **4.04 CONCRETE BEAMS**

Reinforced concrete beams are designed to act together with longitudinal and web reinforcement in resisting applied forces.  Cast-in-place concrete beams are almost always formed and placed along with the slab they support.  Because a portion of the slab acts as an integral part of the beam, the depth of the beam is measured to the top of the slab. 

  * Reinforcing bars extend into and down column support for structural continuity and to develop the required embedment length for anchorage. 
  * Continuity between columns, beams, slabs, and walls is required to minimize bending moments at these junctures.  Because continuity is easily attainable in concrete construction, structures continuous over three or more spans are usually the most efficient. 

  * Diagonal tension results from the principal tensile stresses acting at an angle to the longitudinal axis of a beam. 

  * Hooks are bends given to the end of tension bars to develop an equivalent embedment length for anchorage.  A standard hook is a 90°, 135°, or 180° bend made at the end of a reinforcing bar according to industry standards with a radius based on the bar diameter. 

## **4.05 CONCRETE SLABS**

Concrete slabs are plate structures that are reinforced to span either one or both directions of a structural bay.  Consult a structural engineer and the building code for the required size, spacing, and placement of all reinforcement. 

### **One-Way Slab**

A one-way slab is uniformly thick, reinforced in one direction, and cast integrally with parallel supporting beams. 

### **One-Way Joist Slab**

A joist or ribbed slab is cast integrally with a series of closely spaced joists, which in turn are supported by a parallel set of beams.  Designed as a series of T-beams, joist slabs are more suitable for longer spans and heavier loads than one-way slabs. 

  * See 12.04–12.05 for a discussion of concrete as a construction material. 

**CSI MasterFormat™ 03 20 00: Concrete Reinforcing  
CSI MasterFormat 03 30 00: Cast-in-Place Concrete  
CSI MasterFormat 03 31 00: Structural Concrete**

## **4.06 CONCRETE SLABS**

### **Two-Way Slab and Beam**

A two-way slab of uniform thickness may be reinforced in two directions and cast integrally with supporting beams and columns on all four sides of square or nearly square bays.  Two-way slab and beam construction is effective for medium spans and heavy loads, or when a high resistance to lateral forces is required.  For economy, however, two-way slabs are usually constructed as flat slabs and plates without beams. 

  * A continuous slab, extending as a structural unit over three or more supports in a given direction, is subject to lower bending moments than a series of discrete, simply supported slabs. 

### **Two-Way Waffle Slab**

A waffle slab is a two-way concrete slab reinforced by ribs in two directions.  Waffle slabs are able to carry heavier loads and span longer distances than flat slabs. 

  * Suitable for spans of 24′ to 54′ (7 to 16 m); longer spans may be possible with posttensioning. 
  * For maximum efficiency, bays should be square or nearly square as possible.  Waffle slabs can be efficiently cantilevered in two directions up to ⅓ of the main span.  When no cantilever is present, a perimeter slab band is formed by omitting dome forms. 
  * Coffered underside is usually left exposed. 

## **4.07 CONCRETE SLABS**

### **Two-Way Flat Plate**

A flat plate is a concrete slab of uniform thickness reinforced in two or more directions and supported directly by columns without beams or girders.  Simplicity of forming, lower floor-to-floor heights, and some flexibility in column placement make flat plates practical for apartment and hotel construction. 

  * Suitable for light live to moderate loads over relatively short spans of 12′ to 24′ (3.6 to 7 m)
  * While a regular column grid is most appropriate, some flexibility in column placement is possible. 
  * Shear at column locations governs the thickness of a flat plate. 
  * Punching shear is the potentially high shearing stress developed by the reactive force of a column on a reinforced concrete slab. 

### **Two-Way Flat Slab**

A flat slab is a flat plate thickened at its column supports to increase its shear strength and moment-resisting capacity. 

## **4.08 PRESTRESSED CONCRETE**

Prestressed concrete is reinforced by pretensioning or posttensioning high-strength steel tendons within their elastic limit to actively resist a service load.  The tensile stresses in the tendons are transferred to the concrete, placing the entire cross section of the flexural member in compression.  The resulting compressive stresses counteract the tensile bending stresses from the applied load, enabling the prestressed member to deflect less, carry a greater load, or span a greater distance than a conventionally reinforced member of the same size, proportion, and weight. 

There are two types of prestressing techniques.  Pretensioning is accomplished in a precasting plant, while posttensioning is usually performed at the building site, especially when the structural units are too large to transport from factory to site. 

### **Pretensioning**

Pretensioning prestresses a concrete member by stretching the reinforcing tendons before the concrete is cast. 

  * Steel tendons are first stretched across the casting bed between two abutments until a predetermined tensile force is developed. 

  * Concrete is then cast in formwork around the stretched tendons and fully cured.  The tendons are placed eccentrically in order to reduce the maximum compressive stress to that produced by bending alone. 

  * When the tendons are cut or released, the tensile stresses in the tendons are transferred to the concrete through bond stresses.  The eccentric action of the prestressing produces a slight upward curvature or camber in the member. 

  * The deflection of the member under loading tends to equalize its upward curvature. 

  * A certain amount of initial prestress is lost due to the combined effects of elastic compression or creep of the concrete, relaxation of the steel tendons, frictional losses, and slippage at the anchorages. 

**CSI MasterFormat 03 38 00: Posttensioned Concrete  
CSI MasterFormat 03 40 00: Precast Concrete**

## **4.09 PRESTRESSED CONCRETE**

  * The extremely high-strength steel tendons may be in the form of wire cables, bundled strands, or bars. 

### **Posttensioning**

Posttensioning is the prestressing of a concrete member by tensioning the reinforcing tendons after the concrete has set. 

  * Posttensioned members tend to shorten over time due to elastic compression, shrinkage, and creep.  Adjoining elements that would be affected by this movement should be constructed after the posttensioning process is completed and be isolated from the posttensioned members with expansion joints. 

  * Unstressed steel tendons, draped inside the beam or slab form, are coated or sheathed to prevent bonding while the concrete is cast. 

  * After the concrete has cured, the tendons are clamped on one end and jacked against the concrete on the other end until the required force is developed. 

  * The tendons are then securely anchored on the jacking end and the jack removed.  After the posttensioning process, the steel tendons may be left unbonded, or they may be bonded to the surrounding concrete by injecting grout into the annular spaces around the sheathed strands. 

  * The deflection of the member under loading tends to equalize its upward curvature. 

  * Load balancing is the concept of prestressing a concrete member with draped tendons, theoretically resulting in a state of zero deflection under a given loading condition. 

## **4.10 CONCRETE FORMWORK & SHORING**

Fresh concrete must be shaped and supported by formwork until it cures and can support itself.  This formwork is often designed as a separate structural system by an engineer because of the considerable weight and fluid pressure a concrete mass can exert on it. 

  * Double-post shores may be assembled with cross bracing for relatively heavy loads. 
  * Horizontal shoring consists of adjustable metal members used to support slab forms over comparatively long spans without intervening vertical shores.  Horizontal shoring requires fewer vertical shores, each carrying a comparatively greater load, and leaves open spaces clear for work, but each vertical support carries a greater concentration of load. 
  * After a concrete slab or beam has cured sufficiently to carry its own weight, the original formwork is removed and the slab or beam is reshored until the concrete reaches it full strength. 

  * See 5.07–5.08 for the formwork required for concrete columns and walls. 

  * Flying forms are large sections of formwork, including supporting trusses, beams, or scaffolding, that can be moved by a crane in constructing the concrete floors and roofs of multistory buildings. 

  * Lift-slab construction is a technique of constructing multistory buildings in which all horizontal slabs are cast at ground level and, when cured, are raised into position by hydraulic jacks. 

**CSI MasterFormat 03 10 00: Concrete Forming and Accessories**

## **4.11 PRECAST CONCRETE FLOOR SYSTEMS**

Precast concrete slabs, beams, and structural tees are one-way spanning units that may be supported by sitecast concrete, precast concrete, or masonry bearing walls, or by steel, sitecast concrete, or precast concrete frames.  The precast units are manufactured with normal-density or structural lightweight concrete and prestressed for greater structural efficiency, which results in less depth, reduced weight, and longer spans. 

The units are cast and steam-cured in a plant off-site, transported to the construction site, and set in place as rigid components with cranes.  The size and proportion of the units may be limited by the means of transportation.  Fabrication in a factory environment enables the units to have a consistent quality of strength, durability, and finish, and eliminates the need for on-site formwork.  The modular nature of the standard-sized units, however, may not be suitable for irregular building shapes. 

  * The topping also conceals any surface irregularities, increases the fire-resistance rating of the slab, and accommodates underfloor conduit for wiring. 
  * When the flooring is to be pad and carpet, the topping may be omitted if smooth-surface units are used. 

**CSI MasterFormat 03 40 00: Precast Concrete  
CSI MasterFormat 03 50 00: Cast Decks and Underlayment**

## **4.12 PRECAST CONCRETE UNITS**

  * Use the span ranges indicated for preliminary sizing only.  Consult manufacturer for availability of sizes, exact dimensions, connection details, and span-load tables. 

### **Solid Flat Slabs**

  * 12′ to 24′ (3.6 to 7 m) span range
  * Rule of thumb for depth: span/40

### **Hollow Core Slabs**

  * 12′ to 40′ (3.6 to 12 m) span range
  * Rule of thumb for depth: span/40

### **Single Tees**

  * 30′ to 20′ (9 to 36 m) span range
  * Rule of thumb for depth: span/30

### **Double Tees**

  * 30′ to 100′ (9 to 30 m) span range
  * Rule of thumb for depth: span/20

  * 15′ to 75′ (4.5 to 22 m) span range
  * Rule of thumb for depth: span/15

### **AASHTO Girders**

  * 36′ to 60′ (10 to 18 m) span range

  * AASHTO: American Association of State Highway and Transportation Officials
  * Designed originally for bridge structures but used sometimes in building construction. 

## **4.13 PRECAST CONCRETE CONNECTIONS**

### **Precast Slabs**

### **Precast Slabs**

### **Precast Structural Tees**

### **Precast Beams**

## **4.14 STRUCTURAL STEEL FRAMING**

Structural steel girders, beams, and columns are used to construct a skeleton frame for structures ranging in size from one-story buildings to skyscrapers.  Because structural steel is difficult to work on-site, it is normally cut, shaped, and drilled in a fabrication shop according to design specifications; this can result in relatively fast, precise construction of a structural frame.  Structural steel may be left exposed in unprotected noncombustible construction, but because steel can lose strength rapidly in a fire, fire-rated assemblies or coatings are required to qualify as fire-resistive construction.  In exposed conditions, corrosion resistance is also required.  See 12.08 for a discussion of steel as a construction material; see the Appendix for fire-rated steel assemblies. 

**CSI MasterFormat 05 12 00: Structural Steel Framing**

## **4.15 STRUCTURAL STEEL FRAMING**

### **One-Way Beam System**

### **Two-Way Beam System**

### **Triple Beam System**

  * When a large, column-free space is required, long-spanning plate girders or trusses can be used to carry the primary beam, which in turn support a layer of secondary beams. 

## **4.16 STEEL BEAMS**

  * More structurally efficient wide-flange (W) shapes have largely superseded the classic I-beam (S) shapes.  Beams may also be in the form of channel (C) sections, structural tubing, or composite sections. 

  * The general objective is to use the lightest steel section that will resist bending and shear forces within allowable limits of stress and without excessive deflection for intended use. 
  * In addition to material costs, also consider the labor costs required for erection. 

  * Box girders are built up from shapes and have a hollow, rectangular cross section. 

  * Castellated beams are fabricated by dividing the web of a wide-flange section with a lengthwise zigzag cut, then welding both halves together at the peaks, thus increasing its depth without increasing its weight. 

**CSI MasterFormat 05 12 23: Structural Steel for Buildings**

## **4.17 STEEL BEAM CONNECTIONS**

There are many ways in which steel connections can be made, using different types of connectors and various combinations of bolts and welds.  Refer to the American Institute of Steel Construction's (AISC's) Manual of Steel Construction for steel section properties and dimensions, allowable load tables for beams and columns, and requirements for bolted and welded connections.  In addition to strength and degree of rigidity, connections should be evaluated for economy of fabrication and erection, and for visual appearance if the structure is exposed to view. 

The strength of a connection depends on the sizes of the members and the connecting tees, angles, or plates, as well as the configuration of bolts or welds used.  The AISC defines three types of steel framing that govern the sizes of members and the methods for their connections: moment connections, shear connections, and semi-rigid connections. 

### **Moment Connections**

AISC Type 1—Rigid Frame—connections are able to hold their original angle under loading by developing a specified resisting moment, usually by means of plates welded or bolted to the beam flanges and the supporting column. 

## **4.18 STEEL BEAM CONNECTIONS**

### **Shear Connections**

AISC Type 2—Simple Frame—connections are made to resist only shear and are free to rotate under gravity loads.  Shear walls or diagonal bracing is required for lateral stability of the structure. 

  * A framed connection is a shear-resisting steel connection made by welding or bolting the web of a beam to the supporting column or girder with two angles or a single tab plate. 

  * A seated connection is a shear-resisting steel connection made by welding or bolting the flanges of a beam to the supporting column with a seat angle below and a stabilizing angle above. 

  * A seated connection may be stiffened to resist large beam reactions, usually by means of a vertical plate or pair of angles directly below the horizontal component of the seat angle. 

### **Semi-Rigid Connections**

AISC Type 3—Semi-Rigid Frame—connections assume beam and girder connections possess a limited but known moment-resisting capacity. 

  * All-welded connections are aesthetically pleasing, especially when ground smooth, but they can be very expensive to fabricate. 

## **4.19 OPEN-WEB STEEL JOISTS**

Open-web joists are lightweight, shop-fabricated steel members having a trussed web.  A K series joist has a web consisting of a single bent bar, running in a zigzag pattern between the upper and lower chords.  LH and DLH series joists have heavier web and chord members for increased loads and spans. 

### **Span Ranges for 0pen-web Joists**

  * K series standard joists; 8″ to 30″ (205 to 760) depths

  * LH series longspan joists; 18″ to 48″ (455 to 1220) depths

  * DLH series deep longspan joists are available in 52″ to 72″ (1320 to 1830) depths and can span up to 144′ (44 m). 

**CSI MasterFormat 05 20 00: Metal Joists  
CSI MasterFormat 05 21 00: Steel Joist Framing**

## **4.20 OPEN-WEB JOIST FRAMING**

## **4.21 OPEN-WEB JOIST FRAMING**

  * Limited overhangs are possible by extending the top chords. 
  * Extended ends of steel angles or channel sections are available for short overhangs.  For K series joists, the overhang may extend 5′-6″ (1675), with an allowable load of 300 psf (1 psf = 0.479 kPa). 

  * Small openings may be framed with steel angle headers supported by trimmer joists.  Large openings require structural steel framing. 
  * Header to support tail joist

## **4.22 METAL DECKING**

Metal decking is corrugated to increase its stiffness and spanning capability.  The floor deck serves as a working platform during construction and as formwork for a sitecast concrete slab. 

  * The decking panels are secured with puddle-welds or shear studs welded through the decking to the supporting steel joists or beams. 
  * The panels are fastened to each other along their sides with screws, welds, or button punching standing seams. 
  * If the deck is to serve as a structural diaphragm and transfer lateral loads to shear walls, its entire perimeter must be welded to steel supports.  In addition, more stringent requirements for support and side lap fastening may apply. 

There are three major types of metal decking. 

### **Form Decking**

  * Form decking serves as permanent formwork for a reinforced concrete slab until the slab can support itself and its live load. 

### **Composite Decking**

  * Composite decking serves as tensile reinforcement for the concrete slab to which it is bonded with embossed rib patterns.  Composite action between the concrete slab and the floor beams or joists can be achieved by welding shear studs through the decking to the supporting beam below. 

### **Cellular Decking**

  * Cellular decking is manufactured by welding a corrugated sheet to a flat steel sheet, forming a series of spaces or raceways for electrical and communications wiring; special cutouts are available for floor outlets.  The decking may serve as an acoustic ceiling when the perforated cells are filled with glass fiber. 

  * Rule of thumb for overall depth: span/24
  * Consult the manufacturer for patterns, widths, lengths, gauges, finishes, and allowable spans. 

**CSI MasterFormat 05 30 00: Metal Decking**

## **4.23 LIGHT-GAUGE STEEL JOISTS**

Light-gauge steel joists are manufactured by cold-forming sheet or strip steel.  The resulting steel joists are lighter, more dimensionally stable, and can span longer distances than their wood counterparts but conduct more heat and require more energy to process and manufacture.  The cold-formed steel joists can be easily cut and assembled with simple tools into a floor structure that is lightweight, noncombustible, and dampproof.  As in wood light-frame construction, the framing contains cavities for utilities and thermal insulation and accepts a wide range of finishes. 

### **Types of Light-Gauge Steel Joists**

### **Span Ranges for Light-Gauge Steel Joists**

  * 6″ (150) joists

10′ to 14′ (3050 to 4265)

  * 8″ (205) joists

12′ to 18′ (3660 to 5485)

  * 10″ (255) joists

14′ to 22′ (4265 to 6705)

  * 12″ (305) joists

18′ to 26′ (5485 to 7925)

  * Rule of thumb for estimating joist depth: span/20
  * Consult manufacturer for exact joist dimensions, framing details, and allowable spans and loads. 

**CSI MasterFormat 05 40 00: Cold-Formed Metal Framing  
CSI MasterFormat 05 42 00: Cold-Formed Metal Joist Framing**

## **4.24 LIGHT-GAUGE JOIST FRAMING**

Light-gauge steel joists are laid out in and assembled in a manner similar to wood joist framing. 

## **4.25 LIGHT-GAUGE JOIST FRAMING**

### **Interior Bearing**

### **Exterior Bearing**

### **Interior Bearing**

### **Exterior Bearing**

### **Floor Projections and Openings**

### **Exterior Bearing**

## **4.26 WOOD JOISTS**

Wood joist floors are an essential subsystem of wood light-frame construction.  The dimension lumber used for joists is easily worked and can be quickly assembled on site with simple tools.  Together with wood panel sheathing or subflooring, the wood joists form a level working platform for construction.  If properly engineered, the resulting floor structure can serve as a structural diaphragm to transfer lateral loads to shear walls; consult the building code for specific requirements. 

  * Because wood light-framing is combustible, it must rely on finish flooring and ceiling materials for its fire-resistance rating. 
  * The susceptibility of wood light-framing to decay and insect infestation requires positive site drainage, adequate separation from the ground, appropriate use of pressure-treated lumber, and ventilation to control condensation in enclosed spaces. 
  * See 12.11–12.12 for discussion of wood as a construction material. 

**CSI MasterFormat 06 10 00: Rough Carpentry  
CSI MasterFormat 06 11 00: Wood Framing**

## **4.27 WOOD JOISTS**

### **Span Ranges for Wood Joists**

  * 2x6

up to 10′ (3050)

  * 2x8

8′ to 12′ (2440 to 3660)

  * 2x10

10′ to 14′ (3050 to 4265)

  * 2x12

12′ to 18′ (3660 to 5485)

  * Rule of thumb for estimating joist depth: span/16
  * Joist deflection should not to exceed 1/360 th of span. 
  * The stiffness of the joist framing under stress is more critical than its strength. 
  * If the overall construction depth is acceptable, deeper joists spaced further apart are more desirable for stiffness than shallow joists spaced more closely together. 
  * Consult manufacturer for sizes and spans of laminated veneer lumber joists. 

Bridging consists of wood or metal crossbracing or full-depth blocking between each joist at 8′ (2440) intervals.  Bridging may be required by some building codes if the joist depth is 6 or more times its thickness.  However, it is usually not necessary if the joist ends are supported laterally against rotation and their top compression edges are restrained by sheathing or subflooring. 

## **4.28 WOOD JOIST FRAMING**

### **Platform Framing**

### **Balloon Framing**

### **Beam Pocket**

  * See 5.41–5.42 for discussion of balloon and platform framing. 

## **4.29 WOOD JOIST FRAMING**

Wood joists may be supported by wood or steel beams.  In either case, the elevation of the beam should be coordinated with the perimeter sill condition and how the beam supports the floor joists.  Wood is most susceptible to shrinkage perpendicular to its grain.  For this reason, the total depth of wood construction for both the sill condition and the joist–beam connection should be equalized to avoid subsidence of the floor plane. 

### **Wood Beam w/Joist Hangers**

### **Steel Beam w/Ledger**

### **Wood Beam w/Ledger**

### **Steel Beam Under Joists**

### **Wood Beam w/Lapped or Spliced Joists**

## **4.30 WOOD JOIST FRAMING**

### **Nonbearing Partition ⊥ to Joists—No Partition Below**

### **Nonbearing Partition Parallel to Joists—No Partition Below**

### **Bearing Partition ⊥ to Joists**

### **Bearing Partition Parallel to Joists**

### **Bearing Partition ⊥ to Joists—No Partition Above**

### **Nonbearing Partition Parallel to Joists—No Partition Above**

## **4.31 WOOD JOIST FRAMING**

## **4.32 WOOD SUBFLOORING**

Subflooring is the structural material that spans across floor joists, serves as a working platform during construction, and provides a base for the finish flooring.  The joist and subfloor assembly can also be used as a structural diaphragm to transfer lateral forces to shear walls if constructed according to approved standards.  Consult the building code for requirements. 

  * Subflooring typically consists of plywood, although other nonveneer panel materials such as oriented strand board (OSB), waferboard, and particleboard can be used if manufactured according to approved standards.  Consult the American Plywood Association (APA). 
  * The Span Rating is part of the gradestamp found on the back of each panel.  The first number indicates the maximum rafter spacing for roof sheathing and the second number indicates the maximum joist spacing for subflooring. 

  * Span may be 24″ (610) if 25/32″ (20) wood strip flooring is laid perpendicular to joists. 
  * Underlayment provides impact load resistance and a smooth surface for the direct application of nonstructural flooring materials; may be applied as a separate layer over board or panel subflooring, or be combined in a single thickness with the subfloor panel; when floor is subject to unusual moisture conditions, use panels with exterior glue (Exposure 1) or Exterior plywood. 

### **Panel Subfloor and Underlayment**

Gluing combined subfloor-underlayment panels to the floor joists enables the panels to act together with the joists to form integral T-beam units.  This application system lessens floor creep and squeaking, improves floor stiffness and, in some cases, increases the allowable spans for the joists.  These benefits, of course, are contingent on the quality of the application.  In addition to gluing, the panels are secured with power-driven fasteners or with 6d ring- or screw-shank nails.  Consult the APA for detailed recommendations. 

**CSI MasterFormat 06 16 23: Subflooring; 06 16 26: Underlayment**

## **4.33 PREFABRICATED JOISTS & TRUSSES**

Prefabricated, pre-engineered wood joists and trusses are increasingly used in the place of dimension lumber to frame floors because they are generally lighter and more dimensionally stable than sawn lumber, are manufactured in greater depths and lengths, and can span longer distances. 

  * I-joists are manufactured with sawn or laminated veneer lumber flanges along the top and bottom edges of a single plywood or OSB web. 

  * Rule of thumb for estimating depth of trussed joists: span/18
  * Openings in webs allow the passage of electrical and mechanical lines. 
  * Consult manufacturer for available lengths and depths, recommended spacing and allowable spans, and required bearing conditions. 

**CSI MasterFormat 06 17 00: Shop-Fabricated Structural Wood**

## **4.34 PREFABRICATED JOISTS & TRUSSES**

While the precise form of a prefabricated floor joist or truss varies with the manufacturer, the way they are laid out to frame a floor is similar in principle to conventional wood joist framing.  They are most appropriate for long spans and simple floor plans; complex floor layouts may be difficult to frame. 

### **Top Chord Bearing**

### **Top Chord Bearing @ Interior**

### **Bottom Chord Bearing**

## **4.35 WOOD BEAMS**

### **Solid Sawn Lumber**

In the selection of a wood beam the following should be considered: lumber species, structural grade, modulus of elasticity, allowable bending and shear stress values, and the minimum deflection permitted for the intended use.  In addition, attention should be paid to the precise loading conditions and the types of connections used.  See Bibliography for sources of more detailed span and load tables. 

### **Built-Up Beam**

  * Equal in strength to the sum of the strengths of the individual pieces if none of the laminations are spliced
  * Two members nailed w/ 10d @ 16″ (405) o.c.  staggered and two 10d @ each end
  * Three or more members nailed w/ 20d @ 32″ (815) o.c.  staggered and two 20d @ each end

### **Box Beam**

  * Made by gluing two or more plywood or OSB webs to sawn or LVL flanges. 
  * Engineered to span up to 90′ (27 m)

### **Flitch Beam**

  * Timbers set on edge and bolted side by side to steel plates or sections
  * Engineered design

### **Spaced Beam**

  * Blocked and securely nailed at frequent intervals to enable individual member to act as an integral unit

### **Glue-Laminated Timber**

Glue-laminated timber (CSI MasterFormat 06 18 00) is made by laminating stress-grade lumber with adhesive under controlled conditions, usually with the grain of all plies being parallel.  The advantages of glued-laminated timber over dimension lumber are generally higher allowable unit stresses, improved appearance, and availability of various sectional shapes.  Glue-laminated timbers may be end-joined with scarf or finger joints to any desired length, or edge-glued for greater width or depth. 

### **Parallel Strand Lumber**

Parallel strand lumber (PSL) is a structural lumber product made by bonding long, narrow wood strands together under heat and pressure using a waterproof adhesive.  Parallel strand lumber is a proprietary product marketed under the trademark Parallam, used as beams and columns in post-and-beam construction and for beams, headers, and lintels in light-frame construction. 

### **Laminated Veneer Lumber**

Laminated veneer lumber (LVL) is a structural lumber product made by bonding layers of wood veneers together under heat and pressure using a waterproof adhesive.  Having the grain of all veneers run in the same longitudinal direction results in a product that is strong when edge-loaded as a beam or face-loaded as a plank.  Laminated veneer lumber is marketed under various brand names, such as Microlam, and used as headers and beams or as flanges for prefabricated wood I-joists. 

## **4.36 WOOD BEAM SUPPORTS**

A variety of metal attachments are manufactured for wood-to-wood, wood-to-metal, and wood-to-masonry connections.  These include joist and beam hangers, post bases and caps, framing angles and anchors, and floor ties and holddowns.  Consult manufacturer for specific shapes and sizes, allowable loads, and fastening requirements.  Depending on the magnitude of the loads being resisted or transferred, the connectors may be nailed or bolted. 

### **Masonry or Concrete Wall Support**

### **Foundation Wall Support**

### **Girder Support**

### **Girder Support**

Continuous spans produce more uniform stresses than simple spans, resulting in more efficient use of material.  Any splices should occur at points of minimum bending stress, approximately ¼ to ⅓ of the span on either side of an interior support. 

### **Steel Splice Connector**

### **Mortise Splice**

## **4.37 WOOD POST-BEAM CONNECTIONS**

The size and number of bolts required at a connection depend on the thickness of the members, the species of wood, the magnitude and direction of the load relative to the grain of the wood, and the use of metal connectors.  Shear plate or split-ring connectors, which can develop greater stresses per unit bearing, can be used when there is insufficient area to accommodate the required number of through bolts.  See 5.49 for split-ring and shear plate connectors and bolt spacing guidelines. 

### **Exposed Column Cap**

### **Exposed T-Strap**

### **Continuous Post**

### **Continuous Post**

### **Continuous Beam**

### **Spaced Post**

### **Concealed Connection**

### **Interlocking Connection**

## **4.38 WOOD PLANK-AND-BEAM FRAMING**

Wood plank-and-beam floor systems are typically used with a supporting grid of posts or columns to form a skeleton frame structure.  Using larger but fewer structural members that can span greater distances translates into potential savings in material and labor costs. 

  * Plank-and-beam framing is most effective when supporting moderate, evenly distributed loads; concentrated loads may require additional framing. 
  * When this structural system is left exposed, as is often the case, careful attention must be paid to the species and grade of wood used, the detailing of joints, especially at beam-to-beam and beam-to-post connections, and the quality of workmanship. 
  * Plank-and-beam framing may qualify as heavy timber construction if the structure is supported by noncombustible, fire-resistive exterior walls and the members and decking meet the minimum size requirements specified in the building code. 
  * Disadvantages of the plank-and-beam floor system include its susceptibility to impact sound transmission, and its inherent lack of concealed spaces for thermal insulation, piping, wiring, and ductwork. 

**CSI MasterFormat 06 13 00: Heavy Timber Construction  
CSI MasterFormat 06 15 00: Wood Decking**

## **4.39 WOOD PLANK-AND-BEAM FRAMING**

In the plank-and-beam framing system, the supporting grid of beams should be carefully integrated with the required placement of interior partitions for both structural and visual reasons.  Normally, most partitions in this system are nonloadbearing and may be placed as shown.  If bearing partitions are required, however, they should continue down to a foundation wall or be placed directly over beams large enough to carry the imposed load. 

## **4.40 WOOD DECKING**

### **Types of Wood Decking**

### **Surface Patterns for Exposed Ceilings**

### **Types of Spans**

**Simple Span**

  * Planks simply supported at each end have the most deflection for a given load. 

**Double Span**

  * Most efficient structural use of material of a given length

**Continuous Span**

  * Planks span continuously over four or more supports. 
  * Use of random lengths reduces waste. 
  * Layout must be carefully controlled. 
  * 2′ (610) minimum between end joints in adjacent courses
  * Joints in the same general line must rest on at least one support. 
  * Separate joints in nonadjacent rows by 12" (305) or two rows of planks. 
  * Only one joint should occur in each course between supports. 
  * Each plank must rest on at least one support. 
  * In end spans, one-third of the planks should be free of joints. 

### **Span Ranges**

**CSI MasterFormat 06 15 00: Wood Decking**

# **Chapter 5**  
 **WALL SYSTEMS**

5.02 Wall Systems

5.04 Concrete Columns

5.06 Concrete Walls

5.07 Concrete Formwork

5.09 Concrete Surfacing

5.10 Precast Concrete Walls

5.11 Precast Concrete Wall Panels & Columns

5.12 Precast Concrete Connections

5.13 Tilt-Up Construction

5.14 Masonry Walls

5.16 Unreinforced Masonry Walls

5.18 Reinforced Masonry Walls

5.19 Masonry Columns & Pilasters

5.20 Masonry Arches

5.21 Masonry Lintels

5.22 Expansion & Control Joints

5.23 Masonry Wall Sections

5.26 Masonry Bonding

5.28 Structural Clay Tile

5.29 Glass Block

5.31 Adobe Construction

5.32 Rammed-Earth Construction

5.33 Stone Masonry

5.35 Structural Steel Framing

5.37 Steel Columns

5.39 Light-Gauge Steel Studs

5.40 Light-Gauge Stud Framing

5.41 Balloon Framing

5.42 Platform Framing

5.43 Wood Stud Framing

5.46 Stud Wall Sheathing

5.47 Wood Columns

5.48 Wood Post-and-Beam Framing

5.49 Wood Post-Beam Connections

## **5.02 WALL SYSTEMS**

Walls are the vertical constructions of a building that enclose, separate, and protect its interior spaces.  They may be loadbearing structures of homogeneous or composite construction designed to support imposed loads from floors and roofs, or consist of a framework of columns and beams with nonstructural panels attached to or filling in between them.  The pattern of these loadbearing walls and columns should be coordinated with the layout of the interior spaces of a building. 

In addition to supporting vertical loads, exterior wall constructions must be able to withstand horizontal wind loading.  If rigid enough, they can serve as shear walls and transfer lateral wind and seismic forces to the ground foundation. 

Because exterior walls serve as a protective shield against the weather for the interior spaces of a building, their construction should control the passage of heat, infiltrating air, sound, moisture, and water vapor.  The exterior skin, which may be either applied to or integral with the wall structure, should be durable and resistant to the weathering effects of sun, wind, and rain.  Building codes specify the fire-resistance rating of exterior walls, loadbearing walls, and interior partitions. 

The interior walls or partitions, which subdivide the space within a building, may be either structural or nonloadbearing.  Their construction should be able to support the desired finish materials, provide the required degree of acoustical separation, and accommodate when necessary the distribution and outlets of mechanical and electrical services. 

Openings for doors and windows must be constructed so that any vertical loads from above are distributed around the openings and not transferred to the door and window units themselves.  Their size and location are determined by the requirements for natural light, ventilation, view, and physical access, as well as the constraints of the structural system and modular wall materials. 

## **5.03 WALL SYSTEMS**

### **Structural Frames**

  * Concrete frames are typically rigid frames and qualify as noncombustible, fire-resistive construction. 
  * Noncombustible steel frames may utilize moment connections and require fireproofing to qualify as fire-resistive construction. 
  * Timber frames require diagonal bracing or shear planes for lateral stability and may qualify as heavy timber construction if used with noncombustible, fire-resistive exterior walls and if the members meet the minimum size requirements specified in the building code. 
  * Steel and concrete frames are able to span greater distances and carry heavier loads than timber structures. 
  * Structural frames can support and accept a variety of nonbearing or curtain wall systems. 
  * The detailing of connections is critical for structural and visual reasons when the frame is left exposed. 

### **Concrete and Masonry Bearing Walls**

  * Concrete and masonry walls qualify as noncombustible construction and rely on their mass for their load-carrying capability. 
  * While strong in compression, concrete and masonry require reinforcing to handle tensile stresses. 
  * Height-to-width ratio, provisions for lateral stability, and proper placement of expansion joints are critical factors in wall design and construction. 
  * Wall surfaces may be left exposed. 

### **Metal and Wood Stud Walls**

  * Studs of cold-formed metal or wood are normally spaced @ 16″ or 24″ (406 or 610) o.c.;  this spacing is related to the width and length of common sheathing materials. 
  * Studs carry vertical loads while sheathing or diagonal bracing stiffens the plane of the wall. 
  * Cavities in the wall frame can accommodate thermal insulation, vapor retarders, and mechanical distribution and outlets of mechanical and electrical services. 
  * Stud framing can accept a variety of interior and exterior wall finishes; some finishes require a nail-base sheathing. 
  * The finish materials determine the fire-resistance rating of the wall assembly. 
  * Stud wall frames may be assembled on site or panelized off site. 
  * Stud walls are flexible in form due to the workability of relatively small pieces and the various means of fastening available. 

## **5.04 CONCRETE COLUMNS**

Concrete columns are designed to act together with vertical and lateral reinforcement in resisting applied forces.  Consult a structural engineer and the building code for the required size, spacing, and placement of all reinforcement. 

**CSI MasterFormat™ 03 20 00: Concrete Reinforcing  
CSI MasterFormat 03 30 00: Cast-in-place Concrete  
CSI MasterFormat 03 31 00: Structural Concrete**

## **5.05 CONCRETE COLUMNS**

Reinforced concrete columns are usually cast with concrete beams and slabs to form a monolithic structure. 

  * Columns should be continuous to the building foundation. 

## **5.06 CONCRETE WALLS**

**CSI MasterFormat 03 20 00: Concrete Reinforcing  
CSI MasterFormat 03 30 00: Cast-in-place Concrete  
CSI MasterFormat 03 31 00: Structural Concrete**

## **5.07 CONCRETE FORMWORK**

Concrete formwork for columns and walls may be custom-built for a specific job, but prefabricated, reusable panels are used whenever possible.  The framework and bracing must be able to maintain the position and shape of the forms until the concrete sets. 

### **Column Forms**

  * Fiber forms have a smooth or spiral pattern finish and are disposable. 

  * 1′-0″ to 3′-6″ (305 to 1065) in diameter
  * Sonotube is a trademark for a brand of cylindrical column form made of compressed, resin-impregnated paper. 

### **Wall Forms**

  * The contact surfaces of forms are coated with a parting compound—oil, wax, or plastic—to aid in their removal.  From a design standpoint, the shape of a concrete section must allow for the easy removal of the formwork.  Tapered sections are used where the formwork might otherwise be trapped by the surrounding concrete.  Sharp external corners are usually beveled or rounded to avoid chipping and ragged edges. 

**CSI MasterFormat 03 10 00: Concrete Forming and Accessories**

## **5.08 CONCRETE FORMWORK**

Form ties are required to keep wall forms from spreading under the fluid pressure of newly placed concrete.  While various proprietary forms are available, there are two basic types: snap ties and she bolts. 

Tie holes may be:

**CSI MasterFormat 03 11 16: Architectural Cast-in-Place Concrete Forming  
CSI MasterFormat 03 11 16.13: Concrete Form Liners**

## **5.09 CONCRETE SURFACING**

A variety of surface patterns and textures can be produced by the following methods. 

### **Selection of the Concrete Ingredients**

  * The color of concrete can be controlled with the use of colored cement and aggregates. 
  * Exposed aggregate finishes are produced by sandblasting, etching with an acid, or scrubbing a concrete surface after the initial set in order to remove the outer layer of cement paste and expose the aggregate.  Chemicals can be sprayed on the forms to help retard the setting of the cement paste. 

**Exposed Fine Aggregate**

**Exposed Coarse Aggregate**

### **The Impressions Left by the Forms**

  * Béton brut refers to concrete that is left in its natural state after formwork is removed, especially when the concrete surface reflects the texture, joints, and fasteners of a board form. 
  * Plywood forms can be smooth, or be sandblasted or wirebrushed to accentuate the grain pattern of the face ply. 
  * Sheathing lumber produces a board texture. 
  * Metal or plastic formliners can produce a variety of textures and patterns. 

**Sandblasted Plywood**

**Board-and-Batten Pattern**

**Ribbed Texture Formliner**

### **Treatment after the Concrete Sets**

  * Concrete can be painted or dyed after it has set. 
  * The concrete surface can be sandblasted, rubbed, or ground smooth. 
  * Both smooth and textured surfaces can be bush- or jackhammered to produce coarser textures. 
  * Bushhammered finishes are coarse-textured finishes obtained by fracturing a concrete or stone surface with a power-driven hammer having a rectangular head with a corrugated, serrated, or toothed face. 

**Bushhammered Surface**

**Ribbed Surface Bushhammered**

## **5.10 PRECAST CONCRETE WALLS**

### **Precast Concrete Wall Panels**

Precast concrete wall panels are cast and steam-cured in a plant off site, transported to the construction site, and set in place with cranes as rigid components.  Fabrication in a factory environment enables the units to have a consistent quality of strength, durability, and finish, and eliminates the need for on-site formwork. 

The precast wall panels may be conventionally reinforced or prestressed for greater structural efficiency, reduced panel thicknesses, and longer spans.  In addition to the required tensile, shrinkage, and temperature reinforcement, extra reinforcement may be necessary to resist the stresses of transportation and erection. 

  * Precast wall panels may be of solid, composite, or ribbed construction. 
  * Window and door openings, corbels, and anchoring devices are cast into the wall panels. 

**Ribbed Panels**

  * A variety of quality-controlled surface textures and patterns are available; consult manufacturer. 

**Composite Panels**

**Solid Panels**

### **Precast Concrete Columns**

Precast concrete columns are typically used with precast beams to form a structural frame.  See 4.11.  Because rigid joints are difficult to fabricate in a precast structural frame, shear walls or diagonal bracing are normally relied upon to stabilize the structure against lateral forces. 

  * For preliminary design purposes, the above sizes of precast columns can be assumed to support the indicated floor and roof areas. 

**CSI MasterFormat 03 40 00: Precast Concrete  
CSI MasterFormat 03 41 00: Precast Structural Concrete**

## **5.11 PRECAST CONCRETE WALL PANELS & COLUMNS**

Precast concrete wall panels may serve as bearing walls capable of supporting sitecast concrete or steel floor and roof systems.  Together with precast concrete columns, beams, and slabs, the wall panels form an entirely precast structural system that is inherently modular and fire-resistive.  See also 4.11 and 4.13.  For nonstructural precast concrete panels, see 7.27. 

The lateral stability of a precast concrete structure requires that those floors and roofs that serve as horizontal diaphragms be able to transfer their lateral forces to shear-resisting wall panels.  The wall panels, in turn, must be stabilized by columns or cross walls as they transfer the lateral forces to the ground foundation.  All forces are transferred by a combination of grouted joints, shear keys, mechanical connectors, steel reinforcement, and reinforced concrete toppings. 

  * Precast loadbearing wall panels
  * See 7.27 for nonbearing precast wall panels. 

## **5.12 PRECAST CONCRETE CONNECTIONS**

### **Precast Concrete Slab**

### **Panel Joints**

### **Precast Concrete Slab**

### **Column Splice**

### **Concrete Footings**

### **Column Base**

  * See also 4.13 for column, beam, and slab connections. 
  * Consult a professional engineer and the building code for detailed structural requirements. 

## **5.13 TILT-UP CONSTRUCTION**

Tilt-up construction is a method of casting reinforced concrete wall panels on site in a horizontal position, then tilting them up into their final position.  The principal advantage of tilt-up construction is the elimination of the costs associated with constructing and stripping vertical wall forms; this cost savings is offset by the cost of the crane required to lift the completed wall panels into place. 

  * Once the wall panels are cured to sufficient strength, they are lifted with a crane and set on their footings or piers.  They are then temporarily braced until connections can be made to the remaining part of the structure. 
  * The wall panels must be designed to withstand the stresses of being lifted and moved, which can exceed the in-place loads. 

  * The floor and roof connections are similar to those shown in 4.13 and 5.12.  Shown are typical wall panel connections to adjacent panels and footings. 

### **Foundations**

### **Panel Connections**

**CSI MasterFormat 03 47 13: Tilt-Up Concrete**

## **5.14 MASONRY WALLS**

Masonry walls consist of modular building blocks bonded together with mortar to form walls that are durable, fire-resistant, and structurally efficient in compression.  The most common types of masonry units are bricks, which are heat-hardened clay units, and concrete blocks, which are chemically hardened units.  Other types of masonry units include structural clay tile, structural glass block, and natural or cast stone.  See 12.06–12.07 for a discussion of masonry as a construction material. 

  * Masonry walls may be constructed as solid walls, cavity walls, or veneered walls. 

  * See 7.28–7.29 for masonry veneer systems. 

  * Masonry walls may be unreinforced or reinforced. 
  * Unreinforced masonry walls, also called plain masonry, incorporate horizontal joint reinforcement and metal wall ties to bond the wythes of a solid or cavity wall; see 5.16–5.17 for types of unreinforced masonry walls. 

  * A wythe refers to a continuous vertical section of a wall that is one masonry unit in thickness. 

  * Reinforced masonry walls utilize steel reinforcing bars embedded in grout-filled joints and cavities to aid the masonry in resisting stresses; see 5.18 for reinforced masonry walls. 

  * Masonry bearing walls are typically arranged in parallel sets to support steel, wood, or concrete spanning systems. 

  * Water penetration must be controlled through the use of tooled joints, cavity spaces, flashing, and caulking. 
  * Cavity walls are preferred for their increased resistance to water penetration and improved thermal performance. 
  * Differential movements in masonry walls due to changes in temperature or moisture content, or to stress concentrations, require the use of expansion and control joints. 
  * For installation of thermal insulation, see 7.44. 
  * For fire-resistance ratings of noncombustible masonry walls, see A.12–A.13. 

**CSI MasterFormat 04 20 00: Unit Masonry  
CSI MasterFormat 04 21 00: Clay Unit Masonry  
CSI MasterFormat 04 22 00: Concrete Unit Masonry**

## **5.15 MASONRY WALLS**

### **Minimum Wall Thickness**

  * 8″ (205) minimum nominal thickness for: 
    * Masonry bearing walls
    * Masonry shear walls
    * Masonry parapets; height of parapet not to exceed 3 x parapet thickness
  * 6″ (150) minimum nominal thickness for: 
    * Reinforced masonry bearing walls
    * Solid masonry walls in one-story buildings not more than 9′ (2745) high
    * Masonry walls relied upon for resistance to lateral loading are limited to 35′ (10 m) in height. 

### **Mortar**

Mortar is a plastic mixture of cement or lime, or a combination of both, with sand and water, used as a bonding agent in masonry construction. 

  * CSI MasterFormat 04 05 13: Masonry Mortaring
  * Cement mortar is made by mixing portland cement, sand, and water. 
  * Lime mortar is a mixture of lime, sand, and water that is rarely used because of its slow rate of hardening and low compressive strength. 
  * Cement-lime mortar is a cement mortar to which lime is added to increase its plasticity and water-retentivity. 
  * Masonry cement is a proprietary mix of portland cement and other ingredients, as hydrated lime, plasticizers, air-entraining agents, and gypsum, requiring only the addition of sand and water to make cement mortar. 

  * Type M mortar is a high-strength mortar recommended for use in reinforced masonry below grade or in contact with the earth, as foundation and retaining walls subject to frost action or to high lateral or compressive loads; compressive strength of 2500 psi (17,238 kPa). 
  * Type S mortar is a medium-high-strength mortar recommended for use in masonry where bond and lateral strength are more important than compressive strength; compressive strength of 1800 psi (12,411 kPa). 
  * Type N mortar is a medium-strength mortar recommended for general use in exposed masonry above grade where high compressive and lateral strength are not required; compressive strength of 750 psi (5171 kPa). 
  * Type O mortar is a low-strength mortar suitable for use in interior nonloadbearing walls and partitions. 
  * Type K mortar is a very-low-strength mortar suitable only for use in interior nonloadbearing walls where permitted by the building code. 

## **5.16 UNREINFORCED MASONRY WALLS**

### **Solid Masonry**

Solid masonry walls may be constructed of either solid or hollow masonry units laid contiguously with all joints solidly filled with mortar. 

Single wythe walls are typically of concrete masonry units (CMU) bonded with horizontal joint reinforcement. 

Solid masonry walls may also consist of multiple wythes bonded by grout, corrosion-resistant metal wall ties, or horizontal joint reinforcement. 

**CSI MasterFormat 04 20 00: Unit Masonry  
CSI MasterFormat 04 05 23: Masonry Accessories**

## **5.17 UNREINFORCED MASONRY WALLS**

### **Grouted Masonry**

Grouted masonry walls have all interior joints filled entirely with grout as the work progresses.  The grout used to consolidate the adjoining materials into a solid mass is a fluid portland cement mortar that will flow easily without segregation of the ingredients. 

### **Cavity Walls**

Cavity walls are constructed of a facing and a backing wythe of either solid or hollow masonry units, completely separated by a continuous air space and bonded with metal wall ties or horizontal joint reinforcement.  Cavity walls have two advantages over other types of masonry walls:

**1.**  The cavity enhances the thermal insulation value of the wall and permits the installation of additional thermal insulation material. 

**2.**  The air space acts as a barrier against water penetration if the cavity is kept clear, and if adequate weep holes and flashing are provided. 

**CSI MasterFormat 04 05 16: Masonry Grouting**

## **5.18 REINFORCED MASONRY WALLS**

Reinforced masonry walls use steel reinforcing bars placed in thickened joints or cavities with a fluid grout mix of portland cement, aggregate, and water for greater strength in carrying vertical loads and increased resistance to buckling and lateral forces.  It is essential that a strong bond develop between the reinforcing steel, grout, and masonry units. 

### **Reinforced Grouted Masonry**

### **Reinforced Concrete Unit Masonry**

### **General Requirements**

  * Consult a structural engineer and the building code for the structural requirements of reinforced masonry walls. 

**CSI MasterFormat 04 20 00: Unit Masonry**

## **5.19 MASONRY COLUMNS & PILASTERS**

### **Masonry Columns**

### **Masonry Pilasters**

  * Pilasters are rectangular columns embedded in and projecting slightly from one or both faces of a wall.  In addition to carrying vertical concentrated loads, pilasters provide lateral support for masonry walls. 

## **5.20 MASONRY ARCHES**

Masonry arches utilize the compressive strength of brick and stone to span openings by transforming the vertical forces of a supported load into inclined components.  These outward thrusts of the arching action, which are proportional to the total load and span, and inversely proportional to the rise, must be resisted by abutments adjacent to the opening or by equal but opposite thrusts from adjoining arches.  For bending to be eliminated throughout an arch, the lines of thrust must coincide with the arch axis. 

## **5.21 MASONRY LINTELS**

### **Loads on Lintels**

### **Steel Lintels**

### **Steel Angle Lintels**

### **Reinforced Brick Lintels**

### **Reinforcing for Lintels in 8″ (205) Masonry Walls**

## **5.22 EXPANSION & CONTROL JOINTS**

Masonry materials expand and contract with changes in temperature and moisture content.  Clay masonry units tend to absorb water and expand, while concrete masonry units usually shrink as they dry after manufacture.  Movement joints to accommodate these dimensional changes should be located and constructed so as not to compromise the structural integrity of the masonry wall. 

### **Expansion Joints**

Expansion joints are continuous, unobstructed slots constructed to close slightly to accommodate the moisture expansion of brick and stone masonry surfaces.  Expansion joints should provide lateral stability across the joint, and be sealed to prevent the passage of air and water. 

### **Control Joints**

Control joints are constructed to open slightly to accommodate the shrinkage of a concrete masonry wall as it dries after construction.  Shrinkage cracking can be also controlled by using Type 1 moisture-controlled concrete masonry units and reinforcing horizontal joints. 

Control joints should be sealed to prevent the passage of air and water and interlock to prevent out-of-plane movement.  Joint reinforcement should be interrupted to allow in-plane movement. 

  * Movement joints are also required to prevent the deflection of a steel or concrete structural frame from placing stress on a supported masonry wall or panel.  See 7.28. 

**Control Joint Spacing** | **Vertical Spacing of Joint Reinforcement**  
---|---  
| 16″ (405) | 8″ (205)  
Wall length (L) | 50′ (15 m) | 60′ (18 m)  
L/H ratio | 3 | 4

## **5.23 MASONRY WALL SECTIONS**

The wall sections on this and the following two pages illustrate how concrete, steel, and wood floor and roof systems are supported by and tied to various types of masonry bearing walls.  The bearing area of masonry should be proportioned so as not to exceed the allowable compressive stress of the masonry material.  All floors and roofs that provide lateral support for a masonry wall must be secured at least 6′ (1830) o.c.  with anchors embedded in a reinforced, grouted structural element of the wall. 

### **Concrete Masonry Bearing Wall**

### **Composite Masonry Bearing Wall**

## **5.24 MASONRY WALL SECTIONS**

### **Cavity Bearing Wall**

### **Cavity Bearing Wall**

## **5.25 MASONRY WALL SECTIONS**

## **5.26 MASONRY BONDING**

### **Masonry Terminology**

### **Mortar Joints**

### **Course Heights**

  * Relative course heights are nominal dimensions that include the thickness of the mortar joints. 
  * For lengths, use multiples of 4″, 8″, or 12″ (100, 205, or 305)
  * For brick types and sizes, see 12.06. 
  * Wall thicknesses vary with the type of masonry wall; see 5.14–5.15. 

**CSI MasterFormat 04 05 13: Masonry Mortaring**

## **5.27 MASONRY BONDING**

  * Running bond, commonly used for cavity and veneer walls, is composed of overlapping stretchers. 

  * Common bond has a course of headers between every five or six courses of stretchers; also known as American bond. 

  * Stack bond has successive courses of stretchers with all head joints aligned vertically.  Because units do not overlap, horizontal joint reinforcement is required @ 16″ (405) o.c.  in unreinforced walls. 

  * Flemish bond has alternating headers and stretchers in each course, each header being centered above and below a stretcher.  Flare headers with darker ends are often exposed in patterned brickwork. 

  * Flemish cross bond is a modified Flemish bond in which courses of alternate headers and stretchers alternate with stretching courses. 

  * Flemish diagonal bond is a form of Flemish cross bond in which the courses are offset to form a diamond pattern. 

  * Garden-wall bond, used for lightly loaded boundary walls, has a sequence of a header and three stretchers in each course, with each header being centered over a header in alternate courses. 

  * English bond has alternate courses of headers and stretchers in which the headers are centered on stretchers and the joints between stretchers line up vertically in all courses. 

  * To minimize the cutting of brick and enhancing the appearance of bonding patterns, the major dimensions of masonry walls should be based on the size of the modular units used. 

## **5.28 STRUCTURAL CLAY TILE**

Structural clay tile is hollow tile of fired clay having parallel cells or cores and used typically in constructing walls and partitions. 

  * LB Grade: loadbearing structural clay tile suitable for masonry walls not exposed to frost action, or in exposed masonry where protected by a facing of 3″ (75 mm) or more of stone, brick, terra cotta, or other masonry. 
  * LBX Grade: loadbearing structural clay tile suitable for masonry walls exposed to weathering or frost action. 

Structural facing tile is structural clay tile having a glazed surface and used for facing walls and partitions, especially in areas subject to heavy wear, moisture problems, and strict sanitation requirements. 

  * FTS Grade: structural facing tile suitable for exposed exterior and interior masonry walls and partitions where moderate absorption, slight variation in face dimensions, minor defects in surface finish, and medium color range are acceptable. 
  * FTX Grade: smooth structural facing tile suitable for exposed exterior and interior masonry walls and partitions where low absorption and stain resistance are required, and where a high degree of mechanical perfection, minimum variation in face dimensions, and narrow color range are desired. 

**10″ (255) Cavity Wall**

  * 4″ (100) inner wythe of structural facing tile w/ an outer wythe of brick

**8″ (205) Wall**

  * Two 4″ (100) wythes w/ metal ties

**6″ (150) Wall**

  * A single 6″ (150) wythe or a 2″ wythe and a 4″ (51 and 100) wythe w/ metal ties; each side may have a different color. 

**4″ (100) Wall**

  * A single 4″ (100) wythe or two 2″ (two 51) wythes w/ metal ties

### **Typical Wall Sections**

  * For general masonry wall requirements, see 5.14–5.17. 

**CSI MasterFormat 04 21 23: Structural Clay Tile Masonry**

## **5.29 GLASS BLOCK**

Glass block is a translucent, hollow block of glass with clear, textured, or patterned faces, made by fusing two halves together with a partial vacuum inside.  Glass block may be used in nonloadbearing exterior and interior walls, and in conventionally framed window openings.  The glass block units are laid in Type S or Type N mortar with joints at least ¼″ (6) but not more than ⅜″ (10) thick.  Typically, a wall panel is mortared at the sill support and provided with expansion joints along the top and sides to allow for movement and settling. 

**CSI MasterFormat 04 23 00: Glass Unit Masonry**

## **5.30 GLASS BLOCK**

### **Head Section**

### **Jamb Section**

### **Sill Section**

### **Vertical Stiffener**

### **Horizontal Shelf Support**

### **Typical Glass Block Details**

## **5.31 ADOBE CONSTRUCTION**

Adobe and rammed-earth construction both use unfired, stabilized earth as the primary building material.  Current building codes vary in their acceptance of and requirements for adobe and rammed-earth construction.  However, the use of earth as a building material is an economic necessity in many areas of the world, and both adobe and rammed-earth remain low-cost alternative building systems. 

Adobe is sun-dried clay masonry, traditionally used in countries with little rainfall.  Almost any soil having a 15% to 25% clay content may be used for the mud mixture; soils with a higher clay content may require tempering with sand or straw to make satisfactory bricks.  Gravel or other coarse aggregate may make up 50% of the volume of the mix.  The mixing water should not contain dissolved salts, which can recrystallize and damage the brick upon drying. 

Adobe brick is typically made near the point of use with soil obtained from the excavation of basements or from surplus soil from site grading.  The mud is mixed by hand or by mechanical means and cast in wood or metal forms, which are set on level ground and wetted with water to aid separation of the units.  After initial drying, the units are stacked on edge until fully cured.  The brick units are extremely fragile until completely dry. 

  * The dimensions of adobe brick vary according to locale, but a common size is 10″ (255) x 14″ (355) x 2″ to 4″ (51 to 100) thick.  Thinner bricks dry and cure faster than thicker bricks.  Each brick can weigh 25 to 30 pounds (11 to 14 kg). 
  * Stabilized or treated adobe contains an admixture of portland cement, asphalt emulsion, and other chemical compounds to limit the water absorption of the bricks. 
  * Allowable loads for top-supported adobe columns 10′ (3050) high: 
    * 10″ x 28″ (255 x 710) 12,000 lb. ( 5400 kg)
    * 14″ x 20″ (355 x 510) 13,000 lb. ( 5900 kg)
    * 24″ x 24″ (610 x 610) 28,000 lb. ( 12,700 kg)

  * See 5.32 for general requirements governing both adobe and rammed-earth construction. 
  * LEED® MR Credit 5: Regional Materials

**CSI MasterFormat 04 24 00: Adobe Unit Masonry**

## **5.32 RAMMED-EARTH CONSTRUCTION**

Rammed earth, also called pisé de terre, is another traditional building material.  It is essentially a stiff mixture of clay, silt, sand, and water that is compressed and dried within forms as a wall construction.  The soil mixture should contain less than 50% clay and silt, and a maximum aggregate size of ¼″ (6).  Saltwater should never be used in the mix. 

  * Adobe and rammed-earth have low tensile strength but a compressive strength of 300 psi (14 kPa) or more. 
  * The strength of adobe and rammed-earth construction lies in the mass and homogeneous nature of the wall. 
  * While not as thermally efficient as other insulating materials, adobe and rammed-earth walls serve effectively as thermal mass for heat storage. 
  * LEED MR Credit 5: Regional Materials

### **General Requirements**

## **5.33 STONE MASONRY**

Natural stone is a durable, weather-resistant construction material that may be laid in mortar much like clay and concrete masonry units to make both bearing and nonbearing walls.  Some differences result, however, from the irregular shapes and sizes of rubble, the uneven coursing of ashlar masonry, and the varying physical properties of the different types of stone that may be used in the wall construction. 

Natural stone may be bonded with mortar and laid up in the traditional manner as a double-faced loadbearing wall.  More often, however, stone is used as a facing veneer tied to a concrete or masonry backup wall.  To prevent discoloration of the stone, only nonstaining cement and noncorrosive ties, anchors, and flashing should be used.  Copper, brass, and bronze may stain under certain conditions. 

  * See 7.30 for stone veneer walls. 
  * See 12.10 for a discussion of stone as a construction material. 

  * Random rubble is a masonry wall of broken stones having discontinuous but approximately level beds or courses.  The mortar joints are usually held back of the stone faces to emphasize the natural stone shapes. 

  * Coursed rubble is a masonry wall of broken stones having approximately level bed joints and brought at intervals to continuous level courses. 
  * ½″ to 1-½″ (13 to 38) face joints

  * Squared rubble is a masonry wall built of squared stones of varying sizes and coursed at every third or fourth stone. 

  * Squared rubble is a masonry wall built of squared stones of varying sizes and coursed at every third or fourth stone. 

  * Ashlar refers to squared building stone finely dressed on all faces adjacent to those of other stones so as to permit very thin mortar joints. 

  * Coursed ashlar is built of stones having the same height within each course, but with each course varying in height

  * Broken rangework is ashlar masonry laid in horizontal courses of varying heights, any one of which may be broken at intervals into two or more courses. 

**CSI MasterFormat 04 43 00: Stone Masonry**

## **5.34 STONE MASONRY**

### **Stone Masonry over a Backup Wall**

## **5.35 STRUCTURAL STEEL FRAMING**

Conventional steel-framed structures are constructed of hot-rolled beams and columns, open-web joists, and metal decking.  Since structural steel is difficult to work on site, it is normally cut, shaped, and drilled in a fabrication shop according to design specifications; this can result in relatively fast, precise construction. 

**CSI MasterFormat 05 12 00: Structural Steel Framing**

## **5.36 STRUCTURAL STEEL FRAMING**

Because the columns in a steel frame structure transfer the gravity and lateral loads down to the foundation system, the exterior walls are essentially nonloadbearing curtain walls. 

## **5.37 STEEL COLUMNS**

The most frequently used section for columns is the wide-flange (W) shape.  It is suitable for connections to beams in two directions, and all of its surfaces are accessible for making bolted or welded connections.  Other steel shapes used for columns are round pipes and square or rectangular tubing.  Column sections may also be fabricated from a number of shapes or plates to fit the desired end-use of a column. 

  * W shape

  * Round pipe

  * Rectangular or square tubing

  * Welded plates

  * Cruciform (4 angles)

  * Welded plates

  * Compound columns are structural steel columns encased in concrete at least 2-½″ (64 mm) thick, reinforced with wire mesh. 
  * Composite columns are structural steel sections thoroughly encased in concrete reinforced with both vertical and spiral reinforcement. 

The allowable load on a steel column depends on its cross-sectional area and its slenderness ratio (L/r), where (L) is the unsupported length of the column in inches and (r) is the least radius of gyration for the cross section of the column. 

### **Estimating Guidelines for Steel Columns**

**CSI MasterFormat 05 12 23: Structural Steel for Buildings**

## **5.38 STEEL COLUMNS**

### **Beam Connections**

### **Column Splices**

### **Column Bases**

  * A steel base plate is required to distribute the concentrated load from a column to the concrete foundation to ensure that the allowable stresses in the concrete are not exceeded. 

## **5.39 LIGHT-GAUGE STEEL STUDS**

Light-gauge steel studs are manufactured by cold-forming sheet or strip steel.  The cold-formed steel studs can be easily cut and assembled with simple tools into a wall structure that is lightweight, noncombustible, and dampproof.  Metal stud walls may be used as nonloadbearing partitions or as bearing walls supporting light-gauge steel joists.  As in wood light-frame construction, the stud framing contains cavities for utilities and thermal insulation and accepts a wide range of finishes. 

  * Limit height of 3-⅝″ (90) studs to 12′ (3660). 
  * Limit height of 6″ (150) studs to 20′ (6100). 
  * Limit height of 8″ (205) studs to 28′ (8535). 

**CSI MasterFormat 05 40 00: Cold-Formed Metal Framing  
CSI MasterFormat 05 41 00: Structural Metal Stud Framing**

## **5.40 LIGHT-GAUGE STUD FRAMING**

### **Exterior Wall Section**

### **Exterior Wall**

### **Interior Partition**

### **Stud assembly @ Exterior Corner**

### **@ Partition Intersection**

### **Framing of Openings**

## **5.41 BALLOON FRAMING**

Balloon framing utilizes studs that rise the full height of the frame from the sill plate to the roof plate, with joists nailed to the studs and supported by sills or by ribbons let into the studs.  Balloon framing is rarely used today, but the minimal vertical shrinkage it affords may be desirable for brick veneer and stucco finishes. 

Factors to consider in the selection of an exterior wall finish for stud wall frames include:

  * Stud spacing required
  * Sheathing or backing requirements
  * Color, texture, pattern, and scale desired
  * Standard widths and heights of panel siding
  * Detailing of corners and vertical and horizontal joints
  * Integration of door and window openings into wall pattern
  * Durability, maintenance requirements, and weathering characteristics
  * Heat conductivity, reflectance, and porosity of the material
  * Expansion joints, if required

**CSI MasterFormat 06 10 00: Rough Carpentry  
CSI MasterFormat 06 11 00: Wood Framing**

## **5.42 PLATFORM FRAMING**

Platform framing is a light wood frame having studs only one story high, regardless of the stories built, each story resting on the top plates of the story below or on the sill plates of the foundation wall.  Platform framing is also referred to as western framing. 

## **5.43 WOOD STUD FRAMING**

## **5.44 WOOD STUD FRAMING**

## **5.45 WOOD STUD FRAMING**

## **5.46 STUD WALL SHEATHING**

### **Rated Panel Sheathing**

### **Gypsum Sheathing**

### **Fiberboard Sheathing**

### **Rigid Foam Plastic Sheathing**

**CSI MasterFormat 06 16 00: Sheathing**

## **5.47 WOOD COLUMNS**

Wood columns may be solid, built-up, or spaced.  In selecting a wood column, the following should be considered: lumber species; structural grade; modulus of elasticity; and allowable compressive, bending, and shear stress values permitted for the intended use.  In addition, attention should be paid to the precise loading conditions and the types of connections used. 

Wood columns and posts are loaded axially in compression.  Failure can result from crushing of the wood fibers if the maximum unit stress exceeds the allowable unit stress in compression parallel to the grain.  The load capacity of a column is also determined by its slenderness ratio.  As the slenderness ratio of a column increases, a column can fail from buckling. 

  * Built-up columns may be glue-laminated or mechanically fastened.  Glue-laminated columns may have a higher allowable compressive stress than solid sawn columns, while mechanically fastened columns cannot equal the strength of a solid column of the same dimensions and material. 

### **Estimating Guidelines for Wood Columns**

  * 6x6 may support up to 500 sf (46 m2) of floor and roof area. 
  * 8x8 may support up to 1000 sf (93 m2) of floor and roof area. 
  * 10x10 may support up to 2500 sf (232 m2) of floor and roof area. 

  * Columns are assumed to have an unsupported height of 12′ (3660). 
  * Increased sizes are required for columns supporting heavy loads, rising to greater heights, or resisting lateral forces. 
  * See the Bibliography for sources of more detailed load tables. 
  * Consult a structural engineer for final design requirements. 

## **5.48 WOOD POST-AND-BEAM FRAMING**

Post-and-beam construction uses a framework of vertical posts and horizontal beams to carry both floor and roof loads.  The beams supporting the floor and roof systems transmit their loads to posts or columns that, in turn, carry the loads down to the foundation system. 

### **Heavy Timber Construction**

  * Post-and-beam framing may qualify as heavy timber construction if the plank-and-beam floor and roof structures are supported by noncombustible, fire-resistive exterior walls and the wood members and decking meet the minimum size requirements specified in the building code. 

**CSI MasterFormat 06130: Heavy Timber Construction**

## **5.49 WOOD POST-BEAM CONNECTIONS**

The strength of a post-and-beam connection depends on:

  * The species and grade of lumber used
  * The thickness of the wood members
  * The angle of the resisting force relative to the grain of the wood
  * The size and number of bolts or timber connectors used

The size and number of bolts required for a connection depend on the magnitude of the loads being transferred.  Generally, greater efficiency is achieved with a few large bolts rather than with more smaller ones.  The drawings to the right illustrate general guidelines for the placement of bolts. 

### **Timber Connectors**

If there is insufficient surface contact area to accommodate the required number of bolts, timber connectors can be used.  Timber connectors are metal rings, plates, or grids for transferring shear between the faces of two timber members, used with a single bolt that serves to restrain and clamp the assembly together.  Timber connectors are more efficient than bolts or lag screws used alone because they enlarge the area of wood over which a load is distributed and develop higher stresses per unit of bearing. 

## **5.50 WOOD POST-BEAM CONNECTIONS**

# **Chapter 6**  
 **ROOF SYSTEMS**

6.02 Roof Systems

6.03 Roof Slopes

6.04 Reinforced Concrete Roof Slabs

6.05 Precast Concrete Roof Systems

6.06 Structural Steel Roof Framing

6.07 Steel Rigid Frames

6.08 Steel Trusses

6.09 Truss Types

6.10 Space Frames

6.12 Open-Web Steel Joists

6.13 Open-Web Joist Framing

6.14 Metal Roof Decking

6.15 Cementitious Roof Planks

6.16 Rafter Framing

6.18 Light-Gauge Roof Framing

6.19 Wood Rafters

6.20 Wood Rafter Framing

6.23 Roof Sheathing

6.24 Wood Plank-and-Beam Framing

6.26 Wood Post-Beam Connections

6.28 Wood Trusses

6.30 Wood Trussed Rafters

## **6.02 ROOF SYSTEMS**

The roof system functions as the primary sheltering element for the interior spaces of a building.  The form and slope of a roof must be compatible with the type of roofing—shingles, tiles, or a continuous membrane—used to shed rainwater and melting snow to a system of drains, gutters, and downspouts.  The construction of a roof should also control the passage of moisture vapor, the infiltration of air, and the flow of heat and solar radiation.  And depending on the type of construction required by the building code, the roof structure and assembly may have to resist the spread of fire. 

Like floor systems, a roof must be structured to span across space and carry its own weight as well as the weight of any attached equipment and accumulated rain and snow.  Flat roofs used as decks are also subject to live occupancy loads.  In addition to these gravity loads, the planes of the roof may be required to resist lateral wind and seismic forces, as well as uplifting wind forces, and transfer these forces to the supporting structure. 

Because the gravity loads for a building originate with the roof system, its structural layout must correspond to that of the column and bearing wall systems through which its loads are transferred down to the foundation system.  This pattern of roof supports and the extent of the roof spans, in turn, influences the layout of interior spaces and the type of ceiling that the roof structure may support.  Long roof spans would open up a more flexible interior space while shorter roof spans might suggest more precisely defined spaces. 

The form of a roof structure—whether flat or pitched, gabled or hipped, broad and sheltering, or rhythmically articulated—has a major impact on the image of a building.  The roof may be exposed with its edges flush with or overhanging the exterior walls, or it may be concealed from view, hidden behind a parapet.  If its underside remains exposed, the roof also transmits its form to the upper boundaries of the interior spaces below. 

## **6.03 ROOF SLOPES**

### **Flat Roofs**

  * The slope usually leads to interior drains.  Secondary, emergency overflow roof drains or scuppers are required in cases where water might be trapped if the primary roof drains are blocked. 

  * Flat roofs can efficiently cover a building of any horizontal dimension, and may be structured and designed to serve as an outdoor space. 

### **Sloping Roofs**

  * Sloping roofs may be categorized into 
    * Low-slope roofs—up to 3:12
    * Medium- to high-slope roofs—4:12 to 12:12

  * The roof slope affects the choice of roofing material, the requirements for underlayment and eave flashing, and design wind loads. 
  * Low-slope roofs require roll or continuous membrane roofing; some shingles and sheet materials may be used on 3:12 pitches. 
  * Medium- and high-slope roofs may be covered with shingles, tiles, or sheet materials. 
  * Sloping roofs shed rainwater easily to eave gutters. 

  * The height and area of a sloping roof increase with its horizontal dimensions. 
  * The space under a sloping roof may be usable. 
  * Sloping roof planes may be combined to form a variety of roof forms. 

## **6.04 REINFORCED CONCRETE ROOF SLABS**

Reinforced concrete roof slabs are formed and sitecast in the same manner as the concrete floor systems illustrated on 4.05–4.07.  Roof slabs are normally covered with a type of membrane roofing shown in the cross section below.  See 7.12 for flat roof assemblies. 

  * The edge of a concrete roof slab may be treated in three different ways. 

Reinforced concrete may be designed and cast into a variety of other roof forms, such as folded plates, domes, and shell structures.  See 2.18 and 2.26–2.27. 

**CSI MasterFormat™ 03 20 00: Concrete Reinforcing  
CSI MasterFormat 03 30 00: Cast-in-place Concrete  
CSI MasterFormat 03 31 00: Structural Concrete**

## **6.05 PRECAST CONCRETE ROOF SYSTEMS**

Precast concrete roof systems are similar in form and construction to precast floor systems and use the same types of slab units.  See 4.11–4.13 for general conditions and requirements. 

**Bearing Wall**

**End Wall**

**Bearing Wall**

  * See 4.13 for additional bearing connections. 

**Bearing Wall**

**CSI MasterFormat 03 40 00: Precast Concrete**

## **6.06 STRUCTURAL STEEL ROOF FRAMING**

A flat roof structure may be framed with structural steel members similar to the way steel floors are framed.  See 4.14–4.15. 

**CSI MasterFormat 05 12 00: Structural Steel Framing**

## **6.07 STEEL RIGID FRAMES**

Rigid frames consist of two columns and a beam or girder that are rigidly connected at their joints.  Applied loads produce axial, bending, and shear forces in all members of the frame since the rigid joints restrain the ends of the members from rotating freely.  In addition, vertical loads cause a rigid frame to develop horizontal thrusts at its base.  A rigid frame is statically indeterminate and rigid only in its plane. 

  * Various shapes of rigid frames can be fabricated of steel to span from 30′ to 120′ (9 to 36 m). 
  * Rigid frames typically form one-story structures used for light-industrial buildings, warehouses, and recreational facilities. 

  * Steel frames may be left exposed in unprotected noncombustible construction. 
  * See A.12 for fireproofing of steel structures. 
  * Some building codes reduce the fire-protection requirements for steel roof structures 25′ (7620) or more above the floor. 

**CSI MasterFormat 05 12 13: Architecturally-Exposed Structural Steel Framing**

## **6.08 STEEL TRUSSES**

Steel trusses are generally fabricated by welding or bolting structural angles and tees together to form the triangulated framework.  Because of the slenderness of these truss members, connections usually require the use of steel gusset plates.  Heavier steel trusses may utilize wide-flange shapes and structural tubing. 

  * See 2.16 for more information on trusses. 

**CSI MasterFormat 05 12 00: Structural Steel Framing**

## **6.09 TRUSS TYPES**

  * Flat trusses have parallel top and bottom chords.  Flat trusses are generally not as efficient as pitched or bowstring trusses. 

## **6.10 SPACE FRAMES**

A space frame is a long-spanning three-dimensional plate structure based on the rigidity of the triangle and composed of linear elements subject only to axial tension or compression.  The simplest spatial unit of a space frame is a tetrahedron having four joints and six structural members. 

  * Illustrated are three of the many patterns available. 
  * Typical modules: 4′, 5′, 8′, 12′ (1220, 1525, 2440, 3660)

### **Triangular Grid**

### **Square Grid**

### **Hexagonal Grid**

  * Space frames may be constructed of structural steel pipe, tubing, channels, tees, or W-shapes. 

  * Fabricated connectors join the members. 
  * Consult manufacturer for details, module size, and allowable spans. 

  * Welded connection

  * Bolted connection

  * Threaded connections

**CSI MasterFormat 13 32 13: Metal Space Frames**

## **6.11 SPACE FRAMES**

  * As with other constant-depth plate structures, the supporting bay for a space frame should be square or nearly square to ensure that it acts as a two-way structure. 

  * A space frame should always be supported at a panel point. 

  * Increasing the bearing area of the supports increases the number of members into which shear is transferred and reduces the forces in the members. 

## **6.12 OPEN-WEB STEEL JOISTS**

Roof systems using open-web steel joists are similar in layout and construction to steel joist floor systems.  For joist sizes and span ranges, refer to 4.19–4.21. 

**CSI MasterFormat 05 21 00: Steel Joist Framing**

## **6.13 OPEN-WEB JOIST FRAMING**

### **Parapet: Bearing Wall**

### **Parapet: End Wall**

### **Flush Edge: Bearing Wall**

### **Flush Edge: End Wall**

### **Structural Steel Frame**

### **Parapet Wall**

## **6.14 METAL ROOF DECKING**

Metal roof decking is corrugated to increase its stiffness and ability to span across open-web steel joists or more widely spaced steel beams and to serve as a base for thermal insulation and membrane roofing. 

### **Ribbed Roof Decking**

### **Ribbed Roof Decking**

### **Cellular Roof Decking**

  * Acoustic roof decking used as a sound-absorbing ceiling contains glass fiber between the perforated webs of ribbed decking or in the perforated cells of cellular decking. 
  * Decking profiles vary.  Consult manufacturer for available profiles, lengths, gauges, allowable spans, and installation details. 

**CSI MasterFormat 05 30 00: Metal Decking**

## **6.15 CEMENTITIOUS ROOF PLANKS**

Cementitious roof planks are manufactured with portland cement, lightweight aggregate, an aerating compound, and galvanized welded wire fabric reinforcement. 

Cementitious roof planks may also consist of wood fibers that are chemically processed and bonded under pressure with portland cement.  These structural planks can be used to span wood or steel roof framing and serve as roof sheathing or as permanent formwork for a concrete slab; their undersides may be left exposed as an acoustical ceiling.  They have thermal and acoustic insulation value and may be used in fire-resistant construction. 

**CSI MasterFormat 03 51 13: Cementitious Wood Fiber Decks**

## **6.16 RAFTER FRAMING**

### **Roof Terminology**

### **Gable Roofs**

Gable roofs slope downward in two parts from a central ridge, so as to form a gable at each end. 

## **6.17 RAFTER FRAMING**

### **Hip Roofs**

Hip roofs have sloping ends and sides meeting at an inclined projecting angle. 

### **Gambrel Roofs**

Gambrel roofs are divided on each side into a shallower slope above a steeper one. 

### **Flat Roofs**

Flat roofs are framed in a manner similar to floor joist framing; see 4.26. 

  * The required roof slope may be achieved by shortening some of the joist supports and sloping the joists, or by tapering the insulating layer of the roof deck. 

## **6.18 LIGHT-GAUGE ROOF FRAMING**

Roofs and ceilings may be constructed with light-gauge steel members in a manner similar to wood light-frame construction; see 6.19–6.22.  The light-gauge steel members may also be screwed or welded together to form roof trusses similar to those described in 6.29. 

### **Gable Dormer**

### **Shed Dormer**

  * See 6.16–6.17 for light-frame roof forms and terminology. 

**CSI MasterFormat 05 40 00: Cold-Formed Metal Framing**

## **6.19 WOOD RAFTERS**

Roof structures framed with wood rafters are an essential subsystem of wood light-frame construction.  The dimension lumber used for roof joists and rafters is easily worked and can be quickly assembled on site with simple tools. 

**CSI MasterFormat 06 10 00: Rough Carpentry  
CSI MasterFormat 06 11 00: Wood Framing**

## **6.20 WOOD RAFTER FRAMING**

### **Eave Attachment**

### **Eave Support Conditions**

## **6.21 WOOD RAFTER FRAMING**

It is important to consider how the roof eave detail turns the corner and meets the rake detail. 

### **Exposed Rafters**

### **Closed Rake**

### **Wide Vented Soffit**

### **Rake Overhang**

### **Narrow Vented Soffit**

  * Similar to a wide vented soffit

## **6.22 WOOD RAFTER FRAMING**

### **Parapets**

### **Flat Roof Joists**

## **6.23 ROOF SHEATHING**

Sheathing over wood or light-gauge metal rafters typically consists of APA-rated plywood or nonveneered wood panels.  The panels enhance the stiffness of the rafter framing and provide a solid base for the application of various roofing materials.  Sheathing and underlayment requirements should be in accordance with the recommendations of the roofing manufacturer.  In damp climates not subject to blizzard conditions, spaced sheathing of 1x4 or 1x6 boards may be used with wood shingle or shake roofing.  See 7.04–7.05. 

## **6.24 WOOD PLANK-AND-BEAM FRAMING**

Wood plank-and-beam roof systems typically use the same supporting grid of posts or columns as do plank-and-beam floor systems.  See 4.38 and 5.50. 

  * Roof beams may be supported by: 
    * Timber, steel, or concrete columns
    * Timber or steel girders
    * A reinforced concrete or masonry bearing wall
  * Bearing area should be sufficient to ensure the allowable compressive stresses of the beam and bearing material are not exceeded. 

  * The plank-and-beam framing is often left exposed to the interior with rigid thermal insulation being applied over the roof deck and a vapor retarder.  Exposed structures require thoughtful detailing of connections, the use of quality materials, and careful workmanship. 
  * Plank-and-beam framing offers no concealed spaces for overhead ductwork, pipes, or wiring, except when a layered structure or spaced structural members are used. 
  * Plank-and-beam framing may qualify as heavy timber construction if the structure is supported by noncombustible, fire-resistive exterior walls and the wood members and decking meet the minimum size requirements specified in the building code. 

**CSI MasterFormat 06 13 23: Heavy Timber Construction**

## **6.25 WOOD PLANK-AND-BEAM FRAMING**

There are alternatives for how a plank-and-beam roof structure can be framed, depending on the direction and spacing of the roof beams, the elements used to span the beam spacing, and the overall depth of the construction assembly. 

### **Roof Beams Parallel with Slope**

The roof beams may be spaced 4′ to 8′ (1220 to 2440) o.c.  and spanned with solid or glue-laminated wood decking.  The beams may be supported by girders, columns, or a reinforced concrete or masonry bearing wall. 

In this two-layer system, the roof beams may be spaced farther apart and support a series of purlins.  These purlins, in turn, are spanned with wood decking or a rigid, sheet roofing material. 

### **Roof Beams Perpendicular to Slope**

In this example of a two-layer structure, the roof beams support a conventional system of wood rafters. 

The roof beams may be spaced close enough to be spanned with wood decking.  Spaced farther apart, the beams can support a series of secondary beams parallel with the slope. 

## **6.26 WOOD POST-BEAM CONNECTIONS**

### **Ridge Connection**

### **Post-Beam Connection**

### **Post-Beam Connection**

### **Post-Beam Connection**

### **Post-Beam Connection**

### **Post-Beam Connection**

## **6.27 WOOD POST-BEAM CONNECTIONS**

## **6.28 WOOD TRUSSES**

In contrast to monoplanar trussed rafters, heavier wood trusses can be assembled by layering multiple members and joining them at the panel points with split-ring connectors.  These wood trusses are capable of carrying greater loads than trussed rafters and are spaced farther apart.  Consult a structural engineer for design, bracing, and anchorage requirements. 

  * Wood trusses may be spaced up to 8′ (2440) o.c.,  depending on the spanning capability of the roof decking or planking.  When purlins span across the trusses, the truss spacing may be increased up to 20′ (6095). 

  * Trussed beams are timber beams stiffened by a combination of diagonal truss rods and either compression struts or suspension rods. 

## **6.29 WOOD TRUSSES**

### **Example of a Belgian Truss**

### **Heel Joints**

  * Member sizes and joint details are determined by engineering calculations based on truss type, load pattern, span, and grade and species of lumber used. 
  * The size of compression members is generally governed by buckling while the size of tension members is controlled by tensile stresses at connections. 
  * Consult building code for minimum member thicknesses if trusses are to qualify as heavy timber construction. 

## **6.30 WOOD TRUSSED RAFTERS**

Wood trussed rafters are pre-engineered and shop-fabricated monoplanar trusses.  Because the individual members are subject primarily to compressive and tensile forces, they are typically 2x4s; 2x6s are sometimes used for the top chord.  Trussed rafters are best used when a rectangular plan requires a quantity of a single truss type and clear spans over 18′ (5485).  Consult the truss manufacturer for configurations, allowable spans and loads, and construction details. 

### **Soffited Eave**

### **Overhanging Eave**

**CSI MasterFormat 06 17 53: Shop-Fabricated Wood Trusses**

# **Chapter 7**  
 **MOISTURE & THERMAL PROTECTION**

7.02 Moisture & Thermal Protection

7.03 Underlayment for Shingle Roofing

7.04 Wood Shingles

7.05 Wood Shakes

7.06 Composition Shingles

7.07 Slate Shingles

7.08 Tile Roofing

7.09 Vegetated Roofing

7.10 Sheet Metal Roofing

7.11 Corrugated Metal Roofing

7.12 Flat Roof Assemblies

7.14 Built-Up Roofing Systems

7.15 Single-Ply Roofing Systems

7.17 Roof Drainage

7.18 Flashing

7.19 Roof Flashing

7.21 Flashing Roof Penetrations

7.22 Wall Flashing

7.23 Rainscreen Wall Systems

7.24 Curtain Walls

7.27 Precast Concrete Panels

7.28 Masonry Veneer

7.30 Stone Veneer

7.31 Metal Cladding

7.32 Plywood Siding

7.33 Wood Shingle Siding

7.34 Horizontal Board Siding

7.35 Vertical Board Siding

7.36 Stucco

7.38 Exterior Insulation & Finish Systems

7.39 Thermal Resistance

7.40 Thermal Insulation

7.41 Insulating Materials

7.43 Insulating Roofs & Floors

7.44 Insulating Walls

7.45 Moisture Control

7.46 Vapor Retarders

7.47 Ventilation

7.48 Expansion Joints

7.50 Joint Sealants

## **7.02 MOISTURE & THERMAL PROTECTION**

Roofing materials provide the water-resistant covering for a roof system.  They range in form from virtually continuous, impervious membranes to overlapping or interlocking pieces of shingles and tiles.  The type of roofing that may be used depends on the pitch of the roof structure.  While a sloping roof easily sheds water, a flat roof must depend on a continuous waterproof membrane to contain the water while it drains or evaporates.  A flat roof as well as any well-insulated sloping roof capable of retaining snow may therefore have to be designed to support a greater live load than a moderately or high-pitched roof.  Additional factors to consider in the selection of a roofing material include requirements for installation, maintenance, and durability, resistance to wind and fire, and, if visible, the roofing pattern, texture, and color. 

To prevent water from leaking into a roof assembly and eventually the interior of a building, flashing must be installed along roof edges, where roofs change slope or abut vertical planes, and where roofs are penetrated by chimneys, vent pipes, and skylights.  Exterior walls must also be flashed where leakage might occur – at door and window openings and along joints where materials meet in the plane of the wall. 

Exterior walls also must provide protection from the weather.  While some exterior wall systems, such as solid masonry and concrete loadbearing walls, use their mass as barriers against the penetration of water into the interior of a building, other wall systems, such as cavity walls and curtain walls, use an interior drainage system to carry away any moisture that finds its way through the facing or cladding. 

Moisture is normally present in the interior spaces of a building in the form of water vapor.  When this water vapor reaches a surface cooled by heat loss to the colder outside air, condensation may occur.  This condensation may be visible, as on an uninsulated window pane, or it can collect in concealed roof, wall, or floor spaces.  Means of combating condensation include the correct placement of thermal insulation and vapor retarders, and the ventilation of concealed spaces, such as attics and crawl spaces. 

Potential heat loss or gain through the exterior enclosure of a building is an important factor when estimating the amount of mechanical equipment and energy required to maintain the desired level of environmental comfort in the interior spaces.  The proper selection of building materials, the correct construction and insulation of the building enclosure, and the orientation of a building on its site are the basic means of controlling heat loss and gain. 

Building materials expand and contract due to variations within the normal temperature range, as well as exposure to solar radiation and wind.  To allow for this movement and help relieve the stresses caused by thermal expansion and contraction, expansion joints should be flexible, weathertight, durable, and correctly placed to be effective. 

## **7.03 UNDERLAYMENT FOR SHINGLE ROOFING**

Underlayment protects the roof sheathing from moisture until the roofing shingles are applied.  Once the roofing is applied, the underlayment provides the sheathing with additional protection from wind-driven rain.  The underlayment material should have low vapor resistance so that moisture does not accumulate between the underlayment and the roof sheathing.  Only enough nails are used to hold the underlayment in place until the roofing shingles are applied. 

### **Eave Flashing**

Eave flashing is required whenever there is a possibility that ice might form along the eave and cause melting ice and snow to back up under the roofing shingles. 

### **Underlayment and Sheathing for Shingle Roofs**

## **7.04 WOOD SHINGLES**

Wood shingles and shakes are normally cut from red cedar, although white cedar, redwood, and red cypress shingles may be available.  Red cedar has a fine, even grain and is naturally resistant to water, rot, and sunlight. 

Red cedar shingles are available in 16″ (405), 18″ (455), and 24″ (610) lengths, and in the following grades:

  * No.  1 Premium Grade (Blue Label): 
    * 100% heartwood, 100% clear, 100% edge grain
  * No.  2 Intermediate Grade (Red Label): 
    * 10″ (255) clear on 16″ (405) shingles
    * 11″ (280) clear on 18″ (455) shingles
    * 16″ (405) clear on 24″ (610) shingles
    * Some flat grain permitted
  * No.  3 Utility Grade (Black Label): 
    * 6″ (150) clear on 16″ (405) and 18″ (455) shingles
    * 10″ (255) clear on 24″ (610) shingles

### **Maximum Recommended Exposure in Inches (mm)**

  * Use only corrosion-resistant nails, such as hot-dipped galvanized steel or aluminum-alloy nails.  Two fasteners per shingle are required.  Nails should be driven flush with, but not into the surface of the shingles. 
  * Spaced 1x4 or 1x6 sheathing provides ventilation for the shingles.  Board spacing is equal to the shingle exposure. 

### **Open Valley**

### **Hip Application**

**CSI MasterFormat™ 07 31 29: Wood Shingles and Shakes**

## **7.05 WOOD SHAKES**

While wood shingles are sawn, wood shakes are formed by splitting a short log into a number of tapered radial sections, resulting in at least one textured face.  Shakes are normally 100% clear heart wood, and available in 18″ (150) and 24″ (610) lengths.  Tapersplit and straightsplit shakes have 100% edge grain, while handsplit and resawn shakes have at least 90% edge grain. 

Both wood shingles and shakes are flammable unless chemically treated to receive a UL Class C rating.  A Class B rating may be possible if Class C shingles or shakes are used over a solid roof deck of ⅝″ (16) plywood w/ exterior glue covered with a plastic-coated sheet foil. 

  * Because of the rough texture of wood shakes, a layer of interlayment is laid between each course.  The interlayment, 30 lb.  asphalt-saturated felt, serves as a baffle against wind-driven rain or snow. 

### **Open Valley**

### **Hip Application**

  * Ridge similar to hip construction
  * Preformed ridge and hip units are available. 

## **7.06 COMPOSITION SHINGLES**

Composition shingles have either an inorganic fiberglass base or an organic felt base surfaced on the weather side with colored mineral or ceramic granules.  Inorganic fiberglass base shingles have excellent fire resistance (UL Class A); organic felt base shingles possess only a moderate resistance to fire (UL Class C).  Most composition shingles have tabs with a self-sealing adhesive or locking tabs that make them wind-resistant.  Wind resistance is important when shingles are used on low-slope roofs and in areas subject to high winds. 

### **Shingle Designs**

  * Shingles vary in weight from 205 lb.  to 380 lb.  per square. 
  * One square = 100 sf (9.29 m2)
  * Consult the roofing manufacturer for sizes, patterns, colors, and installation details. 

  * Two-tab square butt

  * Three-tab square butt

  * Random-edge cut

  * Laminated overlay

  * W (width) = 12″ (305)
  * E (exposure) = 5″ (125)
  * TL (top lap) = 7″ (180)
  * HL (head lap) = 2″ (51)

### **Open Valley**

**CSI MasterFormat 07 31 13: Asphalt Shingles  
CSI MasterFormat 07 31 13.13: Fiberglass-Reinforced Asphalt Shingles**

## **7.07 SLATE SHINGLES**

Slate shingles can weigh from 800 to 3600 lb. ( 360 to 1630 kg) per square (9.29 m2) of roof area.  Heavier-than-normal roof framing or decking is therefore required.  Slate shingles may be applied over:

  * Saddle or Boston hip

  * Mitered hip

**CSI MasterFormat 07 31 26: Slate Shingles**

## **7.08 TILE ROOFING**

Tile roofing consists of clay or concrete units that overlap or interlock to create a strong textural pattern.  Like slate, roofing tiles are fire-resistant, durable, and require little maintenance.  They are also heavy (800 to 1000 lb.  per square; 363 to 454 kg per 9.29 m2) and require roof framing that is strong enough to carry the weight of the tiles.  Roofing tiles are normally installed over a solid plywood deck with an underlayment of 30 lb.  or 45 lb.  roofing felt.  Special tile units are used at ridges, hips, rakes, and eaves. 

The following are typical types, dimensions, and weights of clay tiles.  Confirm sizes, weights, and installation details with tile manufacturer. 

  * Mission or Spanish tiles are tapered, semicylindrical roofing tiles laid convex side up to overlap flanking, similar tiles laid concave side up. 

  * Taper allows tiles to nest into the overlapping tiles. 
  * Minimum recommended slope – 4:12
  * 10″ (255) wide; 19″ (485) long
  * Exposure: 16″ (405)

  * Minimum recommended slope – 4:12
  * 14″ (355) wide; 19″ (485) long
  * Exposure: 16″ (405)

  * Minimum recommended slope – 3:12
  * 9″ (230) wide; 12″ (305) long
  * Exposure: 9″ (230)

  * Minimum recommended slope – 3:12
  * 10″ (255) wide; 16″ (405) long
  * Exposure: 13″ (330)

**CSI MasterFormat 07 32 00: Roof Tiles**

## **7.09 VEGETATED ROOFING**

Vegetated roofing, also known as "green roofing," refers to a natural roof covering typically consisting of vegetation planted in engineered soil or growing medium over a waterproof membrane.  While vegetated roofing typically requires a greater initial investment, the natural covering protects the waterproof membrane from daily temperature fluctuations and the ultraviolet radiation of the sun that breaks down conventional roofing systems.  Vegetated roofing also offers environmental benefits, including conserving a pervious area otherwise replaced by a building's footprint, controlling the volume of stormwater runoff, and improving air and water quality. 

The surface temperature of traditional roofing can be up to 90°F (32°C) warmer than the air temperature on a hot summer day.  A vegetated roof, having a much lower surface temperature, helps reduce the heat island effect in urban areas.  The increased insulation value of a vegetated roofing system can also help stabilize indoor air temperatures and humidity and reduce the heating and cooling costs for a building. 

There are three types of vegetated roofing systems: intensive, extensive, and modular block. 

  * Intensive vegetative roofing systems require a minimum of one foot (305) of soil depth to create an accessible roof garden with larger trees, shrubs, grasses, and other landscapes.  They require irrigation and drainage systems to maintain the plant materials, which can add 80 to 150 psf (2870 to 4310 Pa) to the load on the roof structure.  Concrete is usually the best choice for a roof deck. 
  * Extensive vegetative roofing systems are low maintenance and built primarily for their environmental benefit.  The lightweight growing medium they use is typically 4″ to 6″ (100 to 150) in depth and contain small, hardy plants and thick grasses that are accessed for maintenance only.  Extensive vegetative roof systems can add between 15 and 50 psf (715 to 2395 Pa) to the load on the roof structure and can be installed over any properly designed concrete, steel, or wood roof deck. 
  * Modular block systems consist of anodized aluminum containers or recycled polystyrene trays with 3″ to 4″ (75 to100) of engineered soil supporting low-growing plant species.  A pad fastened to the bottom of each block protects the roof surface and allows controlled drainage through the unit.  The typical weight of the system is 12 to 18 psf (575 to 860 Pa). 

LEED SS Credit 6: Stormwater Design  
LEED SS Credit 7: Reduce Heat Island Effect

Vegetative roofing consists of the following layers:

**CSI MasterFormat 07 33 63: Vegetated Roofing**

## **7.10 CORRUGATED METAL ROOFING**

Corrugated or ribbed roofing panels span between roof beams or purlins running across the slope.  The roofing panels may be of:

  * Aluminum with a natural mill or enameled finish
  * Galvanized steel
  * Fiberglass or reinforced plastic
  * Corrugated structural glass

  * Many corrugation and ribbed patterns are available.  Translucent fiberglass or plastic panels with matching profiles are available for use as skylights. 

  * 2′ to 3′ (610 to 915) typical widths
  * Consult roofing manufacturer for material specifications, panel sizes and weights, finishes, allowable spans, and installation details. 

### **Hip**

### **Ridge**

**CSI MasterFormat 07 41 13: Metal Roof Panels**

## **7.11 SHEET METAL ROOFING**

A sheet metal roof is characterized by a strong visual pattern of interlocking seams and articulated ridges and roof edges.  The metal sheets may be of copper, zinc alloy, galvanized steel, or terne metal, a stainless steel plated with an alloy of tin and lead.  To avoid possible galvanic action in the presence of rain water, flashing, fastenings, and metal accessories should be of the same metal as the roofing material.  Other factors to consider in the use of metal roofing are the weathering characteristics and coefficient of expansion of the metal. 

  * Standing seams are made by folding up the adjoining edges against each other, then folding their upper portion over in the same direction a number of times. 

  * Batten seams are made by turning up the adjoining edges against a batten and locking them in place with a metal strip placed over the batten. 

  * Taper batten to allow for expansion of roofing. 
  * Various prefabricated standing and batten seams are available from metal roofing manufacturers. 

  * Lock seams are made by folding up the adjoining edges against each other, folding them over, and flattening the interlock. 

### **Types of Seams**

  * Batten ridge seam

  * Standing ridge seam

  * Roll seams are joints between two pieces of sheet metal in the direction of fall of a curved or sloping roof, made by turning up the adjoining edges against each other, then bending them around to form a cylindrical roll. 

**CSI MasterFormat 07 61 00: Sheet Metal Roofing**

## **7.12 FLAT ROOF ASSEMBLIES**

The construction of a flat roof requires the following elements:

**CSI MasterFormat 07 50 00: Membrane Roofing**

## **7.13 FLAT ROOF ASSEMBLIES**

Thermal insulation provides the required resistance to heat flow through the roof assembly.  It may be installed in three positions: below the structural roof deck, between the roof deck and the roofing membrane, or above the roofing membrane. 

  * When located below the roof deck, the thermal insulation typically consists of batt insulation installed over a vapor retarder.  A ventilated air space between the insulation and the roof deck is required to dissipate any water vapor that migrates into the construction assembly. 

  * When located between the roof deck and the roofing membrane, the thermal insulation may be in the form of a lightweight insulating concrete fill or rigid foam insulation boards capable of supporting the roofing membrane.  Rigid insulation should be installed in at least two staggered layers to minimize heat loss through the joints.  The first layer should be mechanically fastened to resist wind uplift; the upper layers are fully adhered with shot steep asphalt.  When rigid polyurethane, polystyrene, or polyisocyanurate insulation is used, the top layer should be perlite or gypsum board to provide a stable underlayment for the roofing membrane and to comply with building code requirements. 

  * In the protected membrane system, the thermal insulation is placed over the roofing membrane.  In this position, the insulation protects the roofing membrane from temperature extremes but not from almost continual dampness.  The thermal insulation consists of moisture-resistant extruded polystyrene boards laid loosely or adhered to the roofing membrane with hot asphalt.  The insulation is protected from sunlight and held in place by stone ballast laid over a filtration fabric, an integrally bonded concrete facing, or interlocking concrete blocks. 

**CSI MasterFormat 07 22 00: Roof and Deck Insulation  
CSI MasterFormat 07 55 00: Protected Membrane Roofing**

## **7.14 BUILT-UP ROOFING SYSTEMS**

### **Types of Roof Decks or Substrates**

  * Steel deck: 22-gauge minimum; building code may require overlayment of perlite or gypsum board. 
  * Wood: 1″ (25) minimum nominal thickness; should be of well-seasoned lumber with tongue-and-groove or splined joints; knotholes and large cracks should be covered with sheet metal. 
  * Plywood: ½″ (13) minimum thickness, laid with face plies perpendicular to supports spaced no more than 24″ (610) o.c.;  tongue-and-groove joints or blocking under joints. 
  * Structural wood-fiber deck must be dense enough to hold mechanical fasteners. 
  * Cast-in-place concrete should be well-cured, dry, frost-free, smooth, and sloped to drain. 
  * Precast concrete must have all joints grouted; any unevenness between units must be leveled with a vented topping or fill. 
  * Lightweight insulating concrete: must be fully cured and air dried; consult roofing manufacturer for acceptability as a roof deck. 
  * Consult roofing manufacturer for approved types of deck, insulation, and fastenings, installation details, requirements for vapor retarder and venting, and the Underwriters' Laboratories (UL) Fire-Hazard Classification of the roofing assembly. 

  * Minimum recommended slope – 1:48

  * Maximum slope for aggregate surfaces – 3:12

  * Maximum slope for smooth-surface roofs – 6:12 to 9:12

  * For slopes over 1:12, lay plies parallel to slope and back nail to prevent slippage; provide non-nailable decks with treated wood nailers for back- nailing. 

**CSI MasterFormat 07 51 00: Built-Up Bituminous Roofing**

## **7.15 SINGLE-PLY ROOFING SYSTEMS**

Single-ply membrane roofing may be applied in liquid or sheet form.  Large domed, vaulted, or complex roof forms require that the roofing membrane be rolled or sprayed on in liquid form.  Materials used for liquid-applied membranes include silicone, neoprene, butyl rubber, and polyurethane.  On planar roof forms, the roofing membrane may be applied in sheet form.  Sheet materials used for single-ply roofing include:

  * Thermoplastic membranes, which may be heat- or chemically welded. 
  * PVC ( polyvinyl chloride) and PVC alloys
  * Polymer-modified bitumens, asphaltic materials to which polymers have been added for increased flexibility, cohesion, and toughness; often reinforced with glass fibers or plastic films
  * Thermosetting membranes, which can be bonded only by adhesives. 
  * EPDM (ethylene propylene diene monomer), a vulcanized elastomeric material
  * CSPE (chlorosulfonated polyethylene), a synthetic rubber
  * Neoprene (polychloroprene), a synthetic rubber

These materials are very thin – from 0.03″ to 0.10″ (0.8 to 2.5) thick – flexible, and strong.  They vary in their resistance to flame propagation, abrasion, and degradation from ultraviolet rays, pollutants, oils, and chemicals.  Some are reinforced with glass fiber or polyester; others have coatings for greater heat-reflectance or resistance to flame spread.  Consult the roofing manufacturer for:

  * Material specifications
  * Approved types of roof deck, insulation, and fastenings
  * Installation and flashing details
  * Underwriters' Laboratories (UL) Fire-Hazard Classification of the roofing assembly

The details on this and the following page refer to EPDM roofing.  Details for other single-ply membranes are similar in principle.  There are three generic systems for the application of EPDM roofing:

  * Fully adhered system
  * Mechanically fastened system
  * Loose laid, ballasted system

### **Fully Adhered System**

The membrane is fully adhered with bonding adhesive to a smooth-surfaced concrete or wood deck, or to rigid insulation boards that are mechanically fastened to the roof deck.  The membrane is mechanically fastened along the perimeter and at roof penetrations. 

**CSI MasterFormat 07 52 00: Modified Bituminous Membrane Roofing  
CSI MasterFormat 07 53 00: Elastomeric Membrane Roofing  
CSI MasterFormat 07 54 00: Thermoplastic Membrane Roofing**

## **7.16 SINGLE-PLY ROOFING SYSTEMS**

### **Mechanically Fastened System**

After the thermal insulation boards have been mechanically fastened to the roof deck, the membrane is also secured to the deck with plates and fasteners in the membrane splices. 

### **Loose Laid, Ballasted System**

Both the insulation and the membrane are laid loosely over the roof deck and covered with a layer of river-washed gravel or a roof paver system.  The membrane is mechanically fastened to the roof deck only along the perimeter and at roof penetrations. 

## **7.17 ROOF DRAINAGE**

The amount of rain or melting snow a roof and its drainage system must handle is a function of:

  * The roof area leading to the roof drains or gutters
  * The frequency and intensity of the rainfall for the region

Flat roofs should be pitched to roof drains that are located at the low points and that connect to the storm drain system of the building.  A system of scuppers or overflow drains may also be required with the inlet flow 2″ (51) above the low points of the roof. 

Rainwater shed by sloping roofs should be caught by gutters along the eave to prevent ground erosion.  Gutters empty into vertical downspouts or leaders that, in turn, discharge into a dry well or storm sewer system.  In dry climates or for small roof areas with adequate overhangs, gutters may be omitted and a bed of gravel or a masonry strip set in the ground under the eave line. 

Gutters are typically of vinyl, galvanized steel, or aluminum, although copper, stainless steel, terne metal, and wood ones are also available.  Aluminum gutters can be cold-formed on-site in continuous runs without joints. 

**Gutter Shapes**

  * Beveled

  * Half-round

  * K-style

  * Spike and ferrule hangers are spiked to fascia or to rafter tails. 

  * Brackets are screwed to fascia or to rafter tails. 

  * Place gutters below the roof slope line so that snow or ice can slide free

**CSI MasterFormat 07 63 00: Sheet Metal Roofing Specialties**

## **7.18 FLASHING**

Flashing refers to thin continuous pieces of sheet metal or other impervious material installed to prevent the passage of water into a structure from an angle or joint.  Flashing generally operates on the principle that, for water to penetrate a joint, it must work itself upward against the force of gravity, or, in the case of wind-driven rain, it would have to follow a tortuous path during which the driving force would be dissipated.  See also 7.23 for a discussion of pressure-equalized rainscreen wall design. 

Flashing may be exposed or concealed.  Exposed flashing is usually of a sheet metal, such as aluminum, copper, painted galvanized steel, stainless steel, zinc alloy, terne metal, or copper-clad lead.  Metal flashing should be provided with expansion joints on long runs to prevent deformation of the metal sheets.  The selected metal should not stain or be stained by adjacent materials or react chemically with them.  See 12.09. 

Flashing concealed within a construction assembly may be of sheet metal or a waterproofing membrane such as bituminous fabric or plastic sheet material, depending on climate and structural requirements. 

  * Aluminum and lead react chemically with cement mortar. 
  * Some flashing materials can deteriorate with exposure to sunlight. 

  * Water can penetrate a joint through surface tension and capillary action. 
  * Capillary action is a manifestation of surface tension by which the greater adhesion of a liquid to a solid surface than the internal cohesion of the liquid itself causes the liquid to be elevated against a vertical surface. 

### **Flashing Locations**

**CSI 07600: Flashing  
CSI 07620: Sheet Metal Flashing  
CSI 07650: Flexible Flashing**

## **7.19 ROOF FLASHING**

The flashing details on this and the following pages illustrate general conditions and can be adapted for use with various building materials and assemblies.  All dimensions are minimum.  Weather conditions and roof slope may dictate greater overlaps.  Consult the manufacturer for details of flashing and flashing accessories. 

### **Masonry or Concrete Parapet**

### **Stud-Framed Parapet**

### **Low Parapet Wall**

### **Metal Gravel Stop and Fascia**

### **Metal Copings**

### **Metal Gravel Stop**

## **7.20 ROOF FLASHING**

### **Ridge Flashing – Concealed**

### **Ridge Flashing – Exposed**

### **Ridge Vent**

### **Flat to Sloping Roof**

### **Flat to Sloping Roof**

### **Exposed Valley**

### **Top of Shed @ Wall**

### **Eave Flashing**

## **7.21 FLASHING ROOF PENETRATIONS**

### **Chimney Flashing**

### **Skylight**

### **Vertical Wall Flashing**

### **Tall Pipe or Pole**

### **Stack Flashing**

### **Vent Pipe**

## **7.22 WALL FLASHING**

Wall flashing is installed to collect any moisture that may penetrate a wall and divert it to the outside through weep holes.  The drawings on this page illustrate where wall flashing is usually required.  Masonry walls are especially susceptible to water penetration.  Rain penetration can be controlled by properly tooling mortar joints, sealing joints such as those around window and door openings, and sloping the horizontal surfaces of sills and copings.  Cavity walls are especially effective in resisting the penetration of water. 

### **Stud-Framed Wall**

### **Masonry Wall**

## **7.23 RAINSCREEN WALL SYSTEMS**

Water can penetrate exterior wall joints and assemblies by the kinetic energy of raindrops, gravity flow, surface tension, capillary action, and pressure differential.  According to how exterior walls deter water penetration, they can be categorized as follows:

  * Mass wall systems, such as concrete and solid masonry walls, shed most rain at the exterior face, absorb the remainder, and dry by releasing the absorbed moisture as vapor. 
  * Barrier wall systems, such as EIFS walls, rely on a continuous seal at the exterior face, which requires ongoing maintenance to be effective in resisting solar radiation, thermal movement, and cracking. 
  * Drainage walls, such as traditional stucco and clapboard walls, use a drainage plane or moisture barrier between the exterior cladding and supporting wall for additional moisture resistance. 
  * Rainscreen walls consist of an outer layer of cladding (the rainscreen), an air cavity, and a drainage plane on a rigid, water-resistant, and airtight support wall. 

Simple rainscreen walls, such as brick cavity walls and furred-out clapboard walls, rely on cladding to shed most of the rain while the air cavity serves as a drainage layer to remove any water that may penetrate the outer layer.  The cavity should be wide enough to prevent the capillary movement of this water from bridging the cavity and reaching the support wall. 

Pressure differential can drive water through an opening in a wall assembly, no matter how small, when water is present on one side of the opening, and the air pressure on that side is greater than that on the other side.  Pressure-equalized rainscreen (PER) walls utilize vented cladding and an air cavity, often divided into drainable compartments, to facilitate pressure equalization with the outside atmosphere and limit water penetration through joints in the cladding assembly.  The primary seals against air and vapor are located on the indoor side of the air cavity, where they are exposed to little if any water. 

## **7.24 CURTAIN WALLS**

A curtain wall is an exterior wall supported wholly by the steel or concrete structural frame of a building and carrying no loads other than its own weight and wind loads.  A curtain wall may consist of metal framing holding either vision glass or opaque spandrel units, or of thin veneer panels of concrete, stone, masonry, or metal. 

Panel systems consist entirely of precast concrete, masonry, or cut stone units.  The wall units may be one, two, or three stories in height, and may be preglazed or glazed after installation.  Panel systems offer controlled shop assembly and rapid erection, but are bulky to ship and handle. 

While simple in theory, curtain wall construction is complex and requires careful development, testing, and erection.  Close coordination is also required between the architect, structural engineer, contractor, and a fabricator who is experienced in curtain wall construction. 

As with other exterior walls, a curtain wall must be able to withstand the following elements:

## **7.25 CURTAIN WALLS**

### **Sun**

  * Brightness and glare should be controlled with shading devices or the use of reflective or tinted glass. 
  * The ultraviolet rays of the sun can also cause deterioration of joint and glazing materials and fading of interior furnishings. 

### **Temperature**

  * Daily and seasonal variations in temperature cause expansion and contraction of the materials comprising a wall assembly, especially metals.  Allowance must be made for differential movement caused by the variable thermal expansion of different materials. 

  * Heat flow through glazed curtain walls should be controlled by using insulating glass, insulating opaque panels, and by incorporating thermal breaks into metal frames. 
  * Thermal insulation of veneer panels may also be incorporated into the wall units, attached to their backsides, or provided with a backup wall constructed on site. 

### **Water**

  * Rain can collect on the wall surface and be wind-driven under pressure through the smallest openings. 
  * Water vapor that condenses and collects within the wall must be drained to the outside. 

### **Pressure-Equalized Design**

The pressure-equalized design principles outlined in 7.23 become critical in the detailing of curtain walls, especially in larger and taller buildings, where the pressure differential between the outside atmosphere and an interior environment can cause rainwater to migrate through even the smallest openings in wall joints. 

### **Application of Pressure-Equalization Principle in Glazed Curtain Wall**

## **7.26 CURTAIN WALLS**

Any of various metal devices may be used to secure a curtain wall to the structural frame of a building.  Some connections are fixed to resist loads applied from any direction.  Others are designed to resist only lateral wind loads.  These joints typically permit adjustment in three dimensions in order to allow for discrepancies between the dimensions of the curtain wall units and the structural frame, as well as to accommodate the differential movement when the structural frame deflects under loading or when the curtain wall reacts to thermal stresses and changes in temperature. 

### **Structural Steel Frame**

### **Reinforced Concrete Frame**

## **7.27 PRECAST CONCRETE PANELS**

Precast concrete wall panels may be used as nonbearing facings supported by a structural steel or reinforced concrete frame.  See 5.10 for loadbearing precast wall panels. 

  * A variety of quality-controlled smooth and textured finishes are available. 
  * Ceramic tile and thin brick or stone facings may be fixed to the wall panels. 
  * Thermal insulation may be sandwiched in the wall panel, attached to its backside, or provided with a backup wall constructed on site. 

Glass-fiber-reinforced concrete can be used in place of conventionally reinforced concrete to produce much thinner and lighter veneer panels.  The panels are produced by spraying short glass fibers onto a mold with a portland cement and sand slurry.  A variety of three-dimensional panel designs and finishes are possible. 

**CSI MasterFormat 03 45 00: Precast Architectural Concrete  
CSI MasterFormat 07 44 53: Glass-Fiber-Reinforced Cementitious Panels**

## **7.28 MASONRY VENEER**

Masonry veneer construction consists of a single wythe of masonry serving as a weather barrier and anchored but not bonded to a supporting structural frame.  In residential construction, wood or metal stud walls are typically faced with a brick veneer. 

  * See 5.14–5.18 for unreinforced and reinforced masonry wall systems. 

**CSI MasterFormat 04 21 13.13: Brick Veneer Masonry**

## **7.29 MASONRY VENEER**

Masonry veneers can also be used as curtain walls supported by steel or concrete frames. 

## **7.30 STONE VENEER**

Stone facings may be set in mortar and tied to a concrete or masonry backup wall; see 5.33–5.34.  Large stone veneer panels from 1-½″ to 3″ (32 to 75) thick may also be supported by the steel or concrete structural frame of a building in a number of ways. 

  * Monolithic stone panels may be fastened directly to the structural frame of a building. 
  * Stone panels may be mounted on a steel subframe designed to transmit gravity and lateral loads from the slabs to the structural frame of a building.  The subframe consists of vertical steel struts that support horizontal stainless steel or aluminum angles.  Bars welded to the angles engage slots in the lower and upper edges of the stone panels. 

  * Stone veneers may be preassembled into larger panels by mounting the thin slabs on non-corrosive metal framing, or by bonding them to reinforced precast concrete panels with bent stainless steel anchors.  A moisture barrier and bonding agent may be applied between the concrete and stone to prevent concrete salts from staining the stonework. 

The required anchorages should be carefully engineered and take into account the strength of the stone veneer, especially at anchorage points, the gravity and lateral loads to be sustained, and the anticipated range of structural and thermal movement.  Some anchors must carry the weight of the stonework and transfer the load to the supporting structural wall or frame.  Others only restrain the stonework from lateral movement.  Still others must offer resistance to shear.  All connecting hardware should be of stainless steel or nonferrous metal to resist corrosion and prevent staining of the stonework.  Adequate tolerances must be built in to allow for proper fitting and shimming, if necessary. 

**CSI MasterFormat 04 42 00: Exterior Stone Cladding**

## **7.31 METAL CLADDING**

Insulated and bonded metal panels are used primarily to clad industrial-type buildings; see 6.07.  They may have facings of anodized aluminum or steel with porcelain, vinyl, acrylic, or enamel finishes.  The panels are typically 3′ (915) wide and span vertically between horizontal steel girts spaced 8′ to 24′ (2.5 to 7.3 m) apart, depending on the type and profile of panel used.  Consult manufacturer for profiles, sizes, allowable spans, thermal and acoustical ratings, and installation details. 

**CSI MasterFormat 07 42 13: Metal Wall Panels  
CSI MasterFormat 13 34 19: Metal Building Systems**

## **7.32 PLYWOOD SIDING**

Exterior-grade plywood siding panels are typically 4′ x 8′ (1220 x 2440), although 9′ and 10′ (2.8 and 3.0 m) lengths are available.  The most common patterns imitate vertical board siding.  The panel surface may have a grooved, rough-sawn, brushed, or striated texture, and may be stained or treated with a clear water-repellant finish.  Medium-density overlay (MDO) is an exterior plywood panel having a melamine or phenolic resin overlay on one or both sides, providing a smooth base for painting. 

Horizontal joints, which must be protected by flashing or other means, are very noticeable.  These horizontal lines should therefore be coordinated with other exterior wall elements such as window and door openings. 

### **Panel Textures**

**Rough sawn**

**Striated**

**Texture 1-11**

**Channel Groove**

**Reverse Board and Batten**

### **Panel Siding Patterns**

**Vertical Joints**

**Horizontal Joints**

**Interior Corners**

**Exterior Corners**

**CSI MasterFormat 07 46 29: Plywood Siding**

## **7.33 WOOD SHINGLE SIDING**

On exterior walls, wood shingles are laid in uniform courses that resemble lap siding.  The courses should be adjusted to meet the heads and sills of window openings and other horizontal bands neatly.  The shingles may be stained or painted.  Premium-grade shingles can be left unpainted to weather naturally. 

Wood shingle siding may be applied in single or double coursing, with the following exposures:

**Types of Sheathing**

### **Single Coursing Application**

### **Double Coursing Application**

### **Dimension Shingles**

Dimension and fancy butt shingles are cut to uniform widths and shapes.  They are used on walls to create certain effects such as scalloped or fish-scale textures. 

  * Square

  * Arrow

  * Diamond

  * Round

  * Octagonal

  * Half cove

  * Hexagonal

  * Fish scale

### **Corners**

At corners, alternating courses are lapped over the adjacent corner shingles on the other side.  Exposed edges should be treated.  Corner boards can also be used to receive the shingles at both interior and exterior corners.  Building paper should be used to flash corners and wherever the shingles abut wood trim. 

**CSI MasterFormat 07 46 23: Wood Siding**

## **7.34 HORIZONTAL BOARD SIDING**

Horizontal board sidings are available in different forms. 

  * Bevel siding, also known as lap siding, is made by cutting a board diagonally across its cross section so that the siding has one thin edge and one thick edge.  The rough, resawn side can be exposed for stain finishes, while the smooth, planed side can be either painted or stained. 

  * Dolly Varden siding is bevel siding rabbeted along the lower edge to receive the upper edge of the board below it. 

  * Shiplap siding consists of boards joined edge to edge with overlapping rabbeted joints. 

  * Drop siding is composed of boards narrowed along the upper edges to fit into rabbets or grooves in the lower edges, laid horizontally with their backs flat against the sheathing or studs of the wall. 

### **Siding Application**

Horizontal board sidings are fastened through the wall sheathing and into the wall studs with hot-dipped galvanized, aluminum, or stainless steel nails.  Nailing is done to allow the individual boards to expand and contract freely with changes in moisture content.  Board ends should meet over a stud or butt against corner boards or window and door trim; a sealant is usually applied to the board ends during installation and the joints caulked. 

**CSI MasterFormat 07 46 23: Wood Siding**

## **7.35 VERTICAL BOARD SIDING**

Vertical board siding can be laid in various patterns.  Matched boards that interlap or interlock can have flush, V-groove, or beaded joints.  Square-edged boards can be used with other boards or battens to protect their vertical joints and form board-and-board or board-and-batten patterns. 

While horizontal siding is nailed directly to the wall studs, vertical siding requires solid blocking at 24″ (610) o.c.,  or plywood sheathing at least ⅝″ or ¾″ (16 or 19) thick.  Over thinner sheathing, 1x4 furring can be used at 24″ (610) o.c A permeable building paper that allows water vapor to escape to the outside is used under the siding. 

As with other wood siding materials, only hot-dipped galvanized or other corrosion-resistant nails should be used.  Treat ends and edges of siding, and the back of batten strips, with a preservative before installation. 

### **Corners**

### **Alternative Sidings**

A variety of siding materials have been designed to mimic the appearance of traditional wood siding, offer improved durability and resistance to weathering, and reduce maintenance costs.  These alternatives include aluminum siding, vinyl (PVC) siding, and fiber-cement planks and panels.  Consult the following sources for more information on the suitability of these siding alternatives for specific applications. 

  * American Architectural Manufacturers Association (AAMA) Publication 1402 for aluminum siding
  * Vinyl Siding Institute's (VSI) publication on rigid vinyl siding application instructions
  * National Evaluation Service, Inc. (NES) Report No.  NER-405 for cement-fiber products

### **Vertical Joints**

## **7.36 STUCCO**

Stucco is a coarse plaster composed of portland or masonry cement, sand, and hydrated lime, mixed with water and applied in a plastic state to form a hard covering for exterior walls.  This weather- and fire-resistant finish is normally used for exterior walls and soffits, but it can also be used for interior walls and ceilings that are subject to direct wetting or damp conditions. 

### **Stud Wall Base**

### **Masonry or Concrete Base**

### **Stucco Finishes**

The finish coat may have a float, stippled, combed, or pebbled texture.  The finish may be natural or be integrally colored through the use of pigment, colored sand, or stone chips. 

### **Thickness of Portland Cement Stucco**

**CSI MasterFormat 09 24 23: Portland Cement Stucco**

## **7.37 STUCCO DETAILS**

Like gypsum plaster, stucco is a relatively thin, hard, brittle material that requires reinforcement or a sturdy, rigid, unyielding base.  Unlike gypsum plaster, which expands slightly as it hardens, portland cement stucco shrinks as it cures.  This shrinkage, along with the stresses caused by structural movement of the base support and variations in temperature and humidity, can cause the stucco to crack.  Control and relief joints are required to eliminate or minimize any cracking. 

### **@ Soffit**

### **Relief Joints**

  * Relief joints relieve stress by permitting independent movement along the perimeter of a stucco membrane.  They are required where two planes of stucco meet at an internal corner, or where a stucco membrane abuts or is penetrated by a structural element, such as a beam, column, or loadbearing wall. 

### **Plan**

### **Section**

## **7.38 EXTERIOR INSULATION & FINISH SYSTEMS**

Exterior insulation and finish systems (EIFS) are available for cladding the exterior of new structures as well as insulating and refacing existing buildings.  The system consists of a thin layer of synthetic stucco troweled, rolled, or sprayed over a layer of rigid plastic foam insulation. 

EIFS systems are susceptible to leaking around windows and doors because of poor detailing or faulty installation.  There is no internal drainage system that would allow any water that does penetrate the system to escape.  This trapped water can cause the insulation layer to separate from the substrate or the sheathing to deteriorate.  To address this problem, a proprietary system uses a drainage mat installed between an air and water barrier and the insulation layer to allow water to drain to plastic flashings above wall openings and at the base of the wall. 

There are two generic types of EIFS systems: polymer-modified and polymer-based systems.  Polymer-modified systems consist of a portland cement base coat from ¼″ to ⅜″ (6.4 to 9.5 mm) thick, reinforced with metal wire lath or glass-fiber mesh fastened to the insulation layer.  In areas subject to impact, heavy-duty fiberglass mesh is used in place of, or in addition to, the standard mesh.  The finish coat of portland cement is modified with acrylic polymers. 

Polymer-based systems consist of a portland cement or acrylic polymer base coat 1/16″ to ¼″ (1.6 to 6.4 mm) thick, reinforced with glass-fiber mesh embedded at the time of installation.  The finish coat is made with acrylic polymers.  Polymer-based systems are more elastic and crack-resistant than polymer-modified systems, but also more susceptible to denting and puncturing. 

  * Consult standards published by the Exterior Insulation Manufacturers Association (EIMA) for installation details. 

**CSI MasterFormat 07 24 00: Exterior Insulation and Finish Systems**

## **7.39 THERMAL INSULATION**

The primary purpose of thermal insulation is to control the flow or transfer of heat through the exterior assemblies of a building and thereby prevent excessive heat loss in cold seasons and heat gain in hot weather.  This control can effectively reduce the amount of energy required by heating and cooling equipment to maintain conditions for human comfort in a building. 

LEED EA Credit 1: Optimize Energy Performance

### **Recommended Minimum Thermal Resistances of Building Insulation***

* Use these R-values only for preliminary design.  Consult the local or state energy code for specific requirements. 

  * For a discussion of the factors that affect human comfort, see 11.03. 
  * For siting factors that also affect potential heat loss or gain, see Chapter 1. 

**CSI MasterFormat 07 21 00: Thermal Insulation**

## **7.40 THERMAL RESISTANCE OF BUILDING MATERIALS**

## **7.41 INSULATING MATERIALS**

Almost all building materials offer some resistance to heat flow.  To achieve the desired Rt value, however, wall, floor, and roof assemblies usually require the addition of an insulating material.  Below is an outline of the basic materials used to insulate the components and assemblies of a building.  Note that all effective insulating materials usually incorporate some form of captured dead air space. 

  * Batt insulation consists of flexible, fibrous thermal insulation of glass or mineral wool, made in various thicknesses and lengths and in 16″ or 24″ (406 or 610) widths to fit between studs, joists, and rafters in light wood frame construction, sometimes faced with a vapor retarder of kraft paper, metal foil, or plastic sheet.  Batt insulation is also as a component in sound-insulating construction. 

  * Rigid foam insulation is a preformed, nonstructural insulating board of foamed plastic or cellular glass.  Cellular glass insulation is fire-resistant, impervious to moisture, and dimensionally stable, but has a lower thermal-resistance value than foamed plastic insulations, which are flammable and must be protected by a thermal barrier when used on the interior surfaces of a building.  Rigid insulations having closed-cell structures, such as extruded polystyrene and cellular glass, are moisture-resistant and may be used in contact with the earth. 

  * Foamed-in-place insulation consists of a foamed plastic, as polyurethane, that is sprayed or injected into a cavity where it adheres to the surrounding surfaces. 

  * Loose-fill insulation consists of mineral wool fibers, granular vermiculite or perlite, or treated cellulosic fibers, poured by hand or blown through a nozzle into a cavity or over a supporting membrane. 

  * Reflective insulation uses a material of high reflectivity and low emissivity, as paper-backed aluminum foil or foil-backed gypsum board, in conjunction with a dead-air space to reduce the transfer of heat by radiation. 

## **7.42 INSULATING MATERIALS**

The steady state method for calculating heat loss or gain takes into account primarily the total thermal resistance (Rt) of the construction assembly and the differential in air temperature.  Other factors that affect heat loss or gain are:

  * The surface color and reflectivity of the materials used; light colors and shiny surfaces tend to reflect more thermal radiation than dark, textured ones. 
  * The mass of the assembly, which affects the time lag or delay before any absorbed and stored heat is released by the structure; time lag becomes a significant factor with thick, dense materials. 
  * The orientation of the exterior surfaces of a building, which affects solar heat gain as well as exposure to wind and the attendant potential for air infiltration. 
  * Latent heat sources and heat gain from the occupants, lighting, and equipment within a building. 
  * Proper installation of thermal insulation and vapor retarders. 

### **Comparison of R-values for Insulated and Uninsulated Assemblies**

## **7.43 INSULATING ROOFS & FLOORS**

### **Concrete**

### **Steel**

### **Wood**

### **Floor Conditions**

### **Roof Conditions**

## **7.44 INSULATING WALLS**

### **Masonry Cavity Walls**

### **Cast Concrete or Concrete Masonry Walls**

### **Stud Frame Walls**

## **7.45 MOISTURE CONTROL**

Moisture is normally present in the air as water vapor.  Evaporation from occupants and equipment can raise the humidity of the air in a building.  This moisture vapor will transform itself into a liquid state or condense when the air in which it exists becomes completely saturated with all the vapor it can hold and reaches its dew point temperature.  Warm air is capable of holding more moisture vapor and has a higher dew point than cooler air. 

Because it is a gas, moisture vapor always migrates from high to lower pressure areas.  This normally means it tends to diffuse from the higher humidity levels of a building's interior toward the lower humidity levels outside.  This flow is reversed when hot, humid conditions exist outdoors and a building's interior spaces are cooler.  Most building materials offer little resistance to this passage of moisture vapor.  If the moisture vapor comes into contact with a cool surface whose temperature is at or below the dew point of the air, it will condense. 

Condensation can lessen the effectiveness of thermal insulation, be absorbed by building materials, and deteriorate finishes.  Moisture vapor, therefore, must be:

  * Prevented by vapor retarders from penetrating the enclosed spaces of exterior construction;
  * Or be allowed to escape, by means of ventilation, before it can condense into a liquid. 

  * Surface condensation on windows can be controlled by raising the surface temperature with a warm air supply or by using double or triple glazing. 

### **Wall without Insulation**

### **Wall with Insulation**

  * Wall requires a vapor retarder to prevent water vapor from condensing within the layer of insulation.  A vapor retarder becomes more important as the level of thermal insulation increases. 

### **Permeability of Some Building Materials**

* Perm is a unit of water vapor transmission, expressed in grains of vapor per one square foot per hour per inch of mercury pressure difference. 

## **7.46 VAPOR RETARDERS**

A vapor retarder is a material of low permeance installed in a construction to prevent moisture from entering and reaching a point where it can condense into a liquid.  Vapor retarders are normally placed as close as possible to the warm side of insulated construction in temperate and cold climates.  In warm, humid climates, the vapor retarder may have to be placed closer to the outer face of the construction. 

  * Some rigid foam insulation boards have inherent vapor resistance, while other insulating materials have a vapor-retarding facing.  A vapor retarder is most effective, however, when it is applied as a separate layer of aluminum foil, polyethylene film, or treated paper. 

**CSI MasterFormat 07 26 00: Vapor Retarders**

## **7.47 VENTILATION**

### **Whole-House Ventilation**

  * Whole-house ventilators are motor-driven fans for pulling stale air from the living areas of a house and exhausting it through attic and roof vents. 

  * Vapor retarders installed in a seamless manner can result in airtight construction, in which case, a forced-air ventilating system with an air-to-air heat exchanger is required to rid interior spaces of moisture, odors, and pollutants. 

### **Energy-Recovery Ventilation**

  * Energy-recovery ventilation systems are whole-house ventilators that provide a controlled way of ventilating a building while minimizing energy loss through the use of either heat-recovery ventilators or energy-recovery ventilators. 

  * Heat-recovery ventilators (HRV) use a heat-exchange core to transfer heat from the exhaust air stream to the prefiltered fresh air stream in the winter and, during the summer, cool the prefiltered fresh air stream with the exhaust air stream. 
  * Energy-recovery ventilators (ERV) have a heat exchanger that transfers both heat and moisture, cooling and dehumidifying the incoming fresh airstream in the summer while heating and humidifying the cold, drier incoming airstream in the winter. 

### **Roof and Attic Ventilation**

  * Ventilation of concealed roof spaces and attics is provided by eave vents and, on sloping roofs, by vents close to the ridge.  The total net free ventilating area should be at least 1/300th of the area being vented, with at least 50% of the required area being at or along the ridge.  Openings should be protected against the penetration of rain, snow, and insects. 
  * Eave or soffit vents may consist of a continuous screened vent slot or a metal vent strip installed in the eave soffit, or comprise a series of evenly distributed circular plug vents in frieze boards. 

### **Crawl Space Ventilation**

  * Unheated crawl spaces also require ventilation.  Openings should have a net area of at least 1-¼ sf (0.14 m2) for each 25 lineal feet (7620) of perimeter wall.  There should be at least one opening on each side of the crawl space, located as high as possible and near a corner to promote cross ventilation.  Openings should be protected against insects and vermin with wire mesh screening. 

**CSI MasterFormat 07 71 00: Roof Specialties  
CSI MasterFormat 08 90 00: Louvers and Vents**

## **7.48 MOVEMENT JOINTS**

All building materials expand and contract in response to normal changes in temperature.  Some also swell and shrink with changes in moisture content, while others deflect under loading.  Joints must be constructed to allow this movement to occur in order to prevent distortion, cracking, or breaks in the building materials.  Movement joints should provide a complete separation of material and allow free movement while, at the same time, maintaining the weathertightness of the construction. 

### **Types of Movement Joints**

  * Expansion joints are continuous, unobstructed slots constructed between two parts of a building or structure permitting thermal or moisture expansion to occur without damage to either part.  Expansion joints can often serve as control and isolation joints.  See 5.22 for expansion joints in brick masonry walls, 7.29 for horizontal expansion joints in masonry veneer walls, and 10.04 for expansion joints in gypsum plaster. 
  * Control joints are continuous grooves or separations formed in concrete ground slabs and concrete masonry walls to form a plane of weakness and thus regulate the location and amount of cracking resulting from drying shrinkage, thermal stresses, or structural movement.  See 3.19 for control joints in concrete ground slabs and 5.22 for control joints in concrete masonry walls. 
  * Isolation joints divide a large or geometrically complex structure into sections so that differential movement or settlement can occur between the parts.  At a smaller scale, an isolation joint can also protect a nonstructural element from the deflection or movement of an abutting structural member. 

The width of an expansion joint depends on the building material and the temperature range involved.  It varies from ¼″ (6) to 1″ (25) or more, and should be calculated for each specific situation. 

  * The coefficient of surface expansion is approximately twice the linear coefficient. 
  * The coefficient of volume expansion is approximately three times the linear coefficient. 

## **7.49 MOVEMENT JOINTS**

These expansion joint details, although general in nature, have the following elements in common:

  * A joint that creates a complete break through the structure, which is then usually filled with a compressible material
  * A weatherstop that may be in the form of an elastic joint sealant, a flexible waterstop embedded within the construction, or a flexible membrane over flat roof joints. 

### **Wall and Roof Juncture**

### **Flat Roof**

### **Concrete Foundation Wall**

### **Masonry Cavity Wall**

### **Column and Wall Juncture**

### **Expansion Joint Covers**

## **7.50 JOINT SEALANTS**

To provide an effective seal against the passage of water and air, a joint sealant must be durable, resilient, and have both cohesive and adhesive strength.  Sealants can be classified according to the amount of extension and compression they can withstand before failure. 

### **Joint Movement**

  * Compressed

  * As installed

  * Elongated

**CSI MasterFormat 07 92 00: Joint Sealants**

# **Chapter 8**  
 **DOORS & WINDOWS**

8.02 Doors & Windows

8.03 Doors & Doorways

8.04 Door Operation

8.05 Hollow Metal Doors

8.06 Hollow Metal Doorframes

8.08 Wood Flush Doors

8.09 Wood Rail & Stile Doors

8.10 Wood Doorframes

8.11 Sliding Glass Doors

8.12 Folding & Pocket Sliding Doors

8.13 Overhead & Coiling Doors

8.14 Glass Entrance Doors

8.15 Storefronts

8.16 Revolving Doors

8.17 Door Hardware

8.18 Door Hinges

8.19 Door Locksets

8.20 Panic Hardware & Closers

8.21 Weatherstripping & Thresholds

8.22 Window Elements

8.23 Window Operation

8.24 Metal Windows

8.26 Wood Windows

8.28 Glazing Systems

8.30 Insulating Glass

8.31 Glazed Curtain Walls

8.35 Double-Skin Facades

8.36 Skylights

8.37 Skylight Details

8.38 Sunspaces

## **8.02 DOORS & WINDOWS**

Doors and doorways provide access from the outside into the interior of a building as well as passage between interior spaces.  Doorways should therefore be large enough to move through easily and accommodate the moving of furnishings and equipment.  They should be located so that the patterns of movement they create between and within spaces are appropriate to the uses and activities housed by the spaces. 

Exterior doors should provide weathertight seals when closed and maintain the approximate thermal insulation value of the exterior walls they penetrate.  Interior doors should offer the desired degree of visual and acoustical privacy.  All doors should be evaluated for their ease of operation, durability under the anticipated frequency of use, security provisions, and the light, ventilation, and view they may offer.  Further, there may be building code requirements for fire resistance, emergency egress, and safety glazing that must be satisfied. 

There are many types and sizes of windows, the choice of which affects not only the physical appearance of a building, but also the natural lighting, ventilation, view potential, and spatial quality of the building's interior spaces.  As with exterior doors, windows should provide a weathertight seal when closed.  Window frames should have low thermal conductivity or be constructed to interrupt the flow of heat.  Window glazing should retard the transmission of heat and control solar radiation and glare. 

Because door and window units are normally factory-built, their manufacturers may have standard sizes and corresponding rough-opening requirements for the various door and window types.  The size and location of doors and windows should be carefully planned so that adequate rough openings with properly sized lintels can be built into the wall systems that will receive them. 

From an exterior point of view, doors and windows are important compositional elements in the design of building facades.  The manner in which they punctuate or divide exterior wall surfaces affects the massing, visual weight, scale, and articulation of the building form. 

## **8.03 DOORS & DOORWAYS**

### **Doorframes**

  * The detailing of a doorframe establishes the appearance of a doorway.  Depending on the thickness of the wall construction, a doorframe may be set within the rough opening or overlap its edges. 

  * ADA accessibility guidelines require that a threshold, if provided, be no higher than ½″ (13) and beveled with a slope not steeper than 1:2. 
  * Saddle is a raised piece of flooring between the jambs of a doorway, to which a door fits closely so as to prevent its binding when opened. 

### **Minimum Maneuvering Clearances at Doorways**

### **ADA Accessibility Guidelines for Doors**

## **8.04 DOOR OPERATION**

### **Swinging**

  * Exterior and interior use

  * Door normally turns on hinges about a side jamb when pushed or pulled, but may also be pivoted from head jamb and threshold. 
  * Requires space around doorway for door swing; check clearance required
  * Most convenient operation for entry and passage
  * Most effective door type for thermal and acoustic insulation and for weather resistance; can be fire-rated

### **Bypass Sliding**

  * Exterior and interior use

  * Doors slide on overhead track and along guides or a track on the floor. 
  * Requires no operating space but is difficult to seal against weather and sound
  * Offers access only through 50% of doorway width
  * Used on exterior as sliding glass doors
  * Used in interiors primarily for visual screening

### **Surface Sliding**

  * Exterior and interior use

  * Similar to a bypass sliding door but provides access through full width of doorway
  * No operating space required but is difficult to weatherproof
  * Door is surface-hung on an exposed overhead track

### **Pocket Sliding**

  * Interior use

  * Door slides on an overhead track into and out of a recess within the width of a wall. 
  * Doorway has a finished appearance when fully open. 
  * Often used where a normal door swing would interfere with the use of a space

### **Folding**

  * Interior use

  * Hinged door panels fold flat against one another when opened. 
  * Bifold doors divide into two parts, require little operating space, and are used primarily as a visual screen to enclose closet and storage spaces. 
  * Accordion doors are multileafed doors that are used primarily to subdivide interior spaces.  They are hung from an overhead track and open by folding back in the manner of an accordion. 

  * See 8.16 for revolving doors. 

## **8.05 HOLLOW METAL DOORS**

### **Door Designs**

  * Flush

  * Glass

  * Vision

  * Narrow light

  * Full-louvered

  * Vision/louvered

### **Door Finishes**

  * Primed or galvanized for painting
  * Baked enamel paint
  * Vinyl clad

### **Door Construction**

  * Hollow metal doors have face sheets of 16- to 22-gauge steel bonded to a steel channel frame and reinforced with channels, a kraft honeycomb structure, or a rigid plastic-foam core. 

### **Rail-and-Stile Construction**

### **Rail Panel Construction**

### **Flush Construction**

### **Fire Doors**

**UL Label** | **Rating** | **Glazing Permitted: ¼″ (6) wired glass**  
---|---|---  
A | 3 hour | No glass permitted  
B | 1-½ hour | 100 sq.  in. ( 0.06 m2) per leaf  
C | ¾ hour | 1296 sq.  in. ( 0.84 m2) per leaf: 54″ (1370) max.  dimension  
D | 1-½ hour | No glass permitted  
E | ¾ hour | 720 sq.  in. ( 0.46 m2) per light; 54″ (1370) max.  dimension

  * Fire door assemblies, consisting of a fire-resistive door, doorframe, and hardware, are required to protect openings in fire-rated walls.  See 2.07. 
  * Maximum door size: 4′ x 10′ (1220 x 3050)
  * Doorframe and hardware must have a fire-resistance rating similar to that of the door. 
  * Door must be self-latching and be equipped with closers. 
  * Louvers with fusible links are permitted for B and C label doors; maximum area = 576 sq.  in. ( 0.37 m2)
  * No glass and louver combinations are permitted. 

**CSI MasterFormat™ 08 13 13: Hollow Metal Doors**

## **8.06 HOLLOW METAL DOORFRAMES**

### **Standard Double-Rabbet Frame**

### **Single Rabbet Frame**

  * Standard gauges: 14, 16, 18
  * Standard finish: Factory-primed for painting
  * Frame profiles vary with manufacturer
  * Frames are mortised and reinforced to receive hinges, strike, and closer. 

### **Wrap-Around Installation**

### **Butt Frame Installation**

### **Corner Construction**

### **Doorframe Anchors**

  * Wood stud anchor

  * Loose T masonry anchor

  * UL-approved masonry anchor

  * Spacing bracket anchor for existing walls

  * Steel channel stud anchor

  * Adjustable floor clip

  * Minimum of three anchors required per jamb

**CSI MasterFormat 08 12 13: Hollow Metal Frames**

## **8.07 HOLLOW METAL DOORFRAMES**

### **Frame Sizes**

### **Masonry Walls**

### **Wood Stud Walls**

### **Steel Stud Walls**

### **Hollow Metal Stick Systems**

Standard hollow metal frame components may be used to create architectural entrances incorporating a combination of transoms, sidelights, and borrowed lights. 

  * Maximum door size: 4′ x 8′ (1220 x 2440)
  * Minimum jamb depth: 3-¾″ (95)
  * Maximum glass size: 1296 sq.  in. ( 0.84 m2) with a maximum dimension of 4′-6″ (1370)
  * Maximum fire-resistance rating: ¾ hour
  * Consult manufacturer for details. 

## **8.08 WOOD FLUSH DOORS**

### **Door Designs**

  * Flush door

  * Flush door w/ glass inserts

  * Flush door w/ louvered insert

### **Hollow Core Doors**

Hollow core doors have a framework of stiles and rails encasing an expanded honeycomb core of corrugated fiberboard or a grid of interlocking horizontal and vertical wood strips.  They are lightweight but have little inherent thermal or acoustic insulation value.  While intended primarily for interior use, they may be used for exterior doors if bonded with waterproof adhesives. 

### **Solid Core Doors**

Solid core doors have a core of bonded lumber blocks, particleboard, or a mineral composition.  Of these, the bonded lumber core is the most economical and widely used.  The mineral composition core is lightest but has low screw-holding strength and cutouts are difficult.  Solid core doors are used primarily as exterior doors, but they may also be used wherever increased fire resistance, sound insulation, or dimensional stability is desired. 

### **Grades and Finishes**

  * There are three hardwood veneer grades: premium, good, and sound. 
  * Premium grade veneers are suitable for natural, transparent finishes. 
  * Good grade veneers are for transparent or paint finishes. 
  * Sound grade veneers are for paint finishes only; they require two coats to cover surface defects. 
  * Hardboard face panels are suitable for paint finishes. 
  * High-pressure plastic laminates may be bonded to the face panels. 
  * Flush doors may also be factory-finished partially with a seal coat or completely including prefitting and premachining for hinges and locksets. 

### **Special Doors**

  * Fire-rated doors have mineral composition cores. 
  * B-label doors have a 1 hour or 1-½ hour UL-approved rating. 
  * C-label doors have a ¾ hour UL-approved rating. 
  * Sound-insulating doors have faces separated by a void or damping compound.  Special stops, gaskets, and thresholds are also required. 

**CSI MasterFormat 08 14 16: Flush Wood Doors**

## **8.09 WOOD RAIL & STILE DOORS**

### **Door Designs**

  * Panel

  * Panel
  * Various panel designs are available

  * Panel

  * Panel with sash

  * Louvered

  * French door

  * French door w/ divided lights

Wood rail-and-stile doors consist of a framework of vertical stiles and horizontal rails that hold solid wood or plywood panels, glass lights, or louvers in place.  The stiles and rails may be solid softwood or veneered hardwood. 

Batten doors consist of vertical board sheathing nailed at right angles to cross strips or ledgers.  Diagonal bracing is nailed between and notched into the ledgers. 

  * Used primarily for economy in rough construction
  * Usually site-fabricated
  * Tongue-and-groove sheathing is recommended for weathertightness. 
  * Subject to expansion and contraction with changes in moisture content

**CSI MasterFormat 08 14 33: Stile and Rail Wood Doors**

## **8.10 WOOD DOORFRAMES**

### **Exterior Door • Stud Wall**

### **Exterior Door • Masonry Veneer Wall**

### **Interior Door • Stud Wall**

### **General Notes**

  * Most door manufacturers offer doors that are prehung in a doorframe; some doors are also available prefinished and prefitted with all necessary hardware and casing trim. 

  * Head and side jamb conditions are usually similar so that the profile of the casing trim may continue around the doorway. 

## **8.11 SLIDING GLASS DOORS**

### **Typical Sizes**

  * Dimensions are nominal stock sizes; consult manufacturer for stock sizes, required rough or masonry openings, glazing options, and installation details. 
  * As a guide, add 1″ (25) to nominal width for rough framed openings and 3″ (75) for masonry openings. 

Sliding glass doors are available with wood, aluminum, or steel frames.  Wood frames may be treated with preservative, primed for painting, or clad in aluminum or vinyl.  Metal frames are available in a variety of finishes, with thermal breaks and integral windproof mounting fins. 

### **ADA Accessibility Guideline**

  * Thresholds for exterior residential sliding doors should be no higher than for ¾″ (19). 

**CSI MasterFormat 08 32 00: Sliding Glass Doors**

## **8.12 FOLDING & POCKET SLIDING DOORS**

## **8.13 OVERHEAD & COILING DOORS**

  * Wood or Aluminum Panel Doors

  * Wood or Steel Flush Doors

  * Steel or Fiberglass Ribbed Doors

  * Steel or Aluminum Slatted Sections

### **Overhead Doors**

Overhead doors are constructed of one or several leaves of wood, steel, aluminum, or fiberglass and open by swinging or rolling up to a position above the door opening.  The door may be operated manually, or by a chain hoist or electric motor. 

  * Overhead doors are available up to 20′ (6095) high and 30′ (9145) wide. 

### **Coiling Doors**

Coiling or rolling doors consist of horizontal, interlocking metal slats guided by a track on either side and open by coiling about an overhead drum at the head of the door opening.  The door may be operated by a chain hoist or electric motor. 

  * Coiling doors are available up to 24′ (7315) high and 32′ (9755) wide. 

  * Both overhead and coiling doors are available with vision panels, pass-through sections, thermal insulation, and other options.  Consult the door manufacturer for available sizes, designs, and installation requirements. 

**CSI MasterFormat 08 33 00: Coiling Doors and Grilles  
CSI MasterFormat 08 36 00: Panel Doors**

## **8.14 GLASS ENTRANCE DOORS**

### **Glass Doors**

Glass doors are constructed of heat-strengthened or tempered glass, with or without rails or stiles, and used primarily as entrance doors. 

  * Consult the building code for requirements when used as an emergency exit door. 
  * Consult manufacturer for sizes, glazing options, and frame requirements. 

  * Door may be offset in frame to swing in one direction only or be center-hung for double-acting operation. 

  * Pivoted doors are carried on and swing about on a center or offset pivot, as distinguished from one hung on hinges. 
  * Balanced doors are pivoted doors that are partially counterbalanced for easier opening and closing. 
  * Automatic doors open automatically at the approach of a person or automobile when actuated by a radio transmitter, electric eye, or other device. 

### **Frameless Doors**

  * Continuous top and bottom rails w/ locks

  * Continuous bottom rail w/ lock

  * Corner pivots w/ bottom lock

### **Framed Doors**

  * Narrow Stile

  * Medium Stile

  * Wide Stile

**CSI MasterFormat 08 41 00: Entrances and Storefronts**

## **8.15 STOREFRONTS**

Storefronts are coordinated systems of extruded metal frames, glass panels, glass entrance doors, and hardware fittings.  The size and spacing of the mullions are determined by the glass strength and thickness and the wind load on the wall plane.  The deflection normal to the wall plane should be limited to 1/200 of each component's clear span; the deflection of glass supports should be limited to 1/300 of the support distance. 

  * Consult manufacturer for frame profiles, sizes, finishes, glazing options, and installation details. 
  * Consult the building code for safety glazing requirements. 

All-glass wall systems use glass mullions and structural silicone sealant to support the glazing.  The thickness of the glass mullions is related to the width and height of the glass panels and the wind load on the wall plane.  Consult the glass manufacturer for sizing and installation requirements. 

  * Butt-joint glazing is a glazing system in which the glass panes or units are supported at the head and sill in a conventional manner, with their vertical edges being joined with a structural silicone sealant without mullions. 

  * Glass mullion system is a glazing system in which sheets of tempered glass are suspended from special clamps, stabilized by perpendicular stiffeners of tempered glass, and joined by a structural silicone sealant and by metal patch plates at corners and edges. 

## **8.16 REVOLVING DOORS**

Revolving doors consist of three or four leaves that rotate about a central, vertical pivot within a cylindrically shaped vestibule.  Used typically as entrance doors in large commercial and institutional buildings, revolving doors provide a continuous weatherseal, eliminate drafts, and hold heating and cooling losses to a minimum while accommodating traffic up to 2000 persons per hour. 

  * 6′-6″ (1980) diameter for general use; 7′-0″ (2135) diameter or greater for high traffic areas
  * An optional speed control automatically aligns doors at quarter points when not in use and turns wings ¾ of a revolution at walking speed when activated by slight pressure. 
  * Some revolving doors have leaves that automatically fold back in the direction of egress when pressure is applied, providing a legal passageway on both sides of the door pivot. 
  * Some building codes may credit revolving doors with satisfying 50% of the legal exit requirements.  Other codes do not credit revolving doors and require adjacent hinged doors for use as emergency exits. 

### **Revolving Door Layouts**

  * Enclosure flanked by hinged doors

  * Enclosure set within a wall plane

  * Enclosure projecting from sidelights

  * Bank of enclosures with sidelights between

  * Sidelights centered on enclosure

  * Enclosure set back within a wall recess

**CSI MasterFormat 08 42 33: Revolving Door Entrances**

## **8.17 DOOR HARDWARE**

Finish door hardware for doors include the following items:

  * Locksets incorporating locks, latches, and bolts, a cylinder and stop works, and operating trim
  * Hinges
  * Closers
  * Panic hardware
  * Push and pull bars and plates
  * Kick plates
  * Door stops, holders, and bumpers
  * Thresholds
  * Weatherstripping
  * Door tracks and guides

Hardware selection factors:

  * Function and ease of operation
  * Recessed or surface-mounted installation
  * Material, finish, texture, and color
  * Durability in terms of anticipated frequency of use and possible exposure to weather or corrosive conditions

### **Hardware Locations**

### **ADA Accessibility Guidelines**

  * Door handles, pulls, latches, and locks should be easy to grasp with one hand without tight grasping, pinching, or twisting of the wrist. 
  * Hardware should be mounted within the reach ranges specified in A.03. 

### **Door Hand Conventions**

Door hand conventions are used in specifying door hardware such as locksets and closers.  The terms right and left assume a view from the exterior of the building or room to which the doorway leads. 

  * Left hand (LH)
  * Door opens inward; hinges on left

  * Right hand (RH)
  * Door opens inward; hinges on right

  * Left hand reverse (LHR)
  * Door opens outward; hinges on left

  * Right hand reverse (RHR)
  * Door opens outward; hinges on right

### **Hardware Finishes**

**CSI MasterFormat 08 71 00: Door Hardware**

## **8.18 DOOR HINGES**

### **Butt Hinges**

Butt hinges are composed of two plates or leaves joined by a pin and secured to the abutting surfaces of wood and hollow metal doors and door jambs. 

  * Full-mortise hinges have both leaves fully mortised into the abutting surfaces of a door and door jamb so that only the knuckle is visible when the door is closed. 
  * Template hinges are mortise hinges manufactured to fit the recess and match the arrangement of holes of hollow metal doors and frames; non-template hinges are used for wood doors. 
  * Half-mortise hinges have one leaf mortised into the edge of a door and the other surface-mounted to the doorframe. 
  * Half-surface hinges have one leaf mortised into a doorframe and the other surface-mounted to the face of the door. 
  * Full-surface hinges have two leaves surface-mounted to the adjacent faces of a door and doorframe. 

  * The pin in the knuckle may be removable (loose) so that a door can be unhung by separating the two leaves or fixed (nonrising).  Self-locking pins which cannot be removed when the door is closed are also available for security. 

### **Hinge Size**

  * Hinge width is determined by door thickness and clearance required. 
  * Hinge height is determined by the door width and thickness. 

### **Special-Purpose Hinges**

  * Parliament hinges have T-shaped leaves and a protruding knuckle so that a door can stand away from the wall when fully opened. 

**CSI MasterFormat 08 71 00: Door Hardware**

## **8.19 DOOR LOCKSETS**

Locksets are manufactured assemblies of parts making up a complete locking system, including knobs, plates, and a locking mechanism.  Described below are the major types of locksets: mortise locks, unit and integral locks, and cylinder locks.  Consult hardware manufacturer for lockset functions, installation requirements, trim designs, dimensions, and finishes. 

### **Mortise Lock**

  * Mortise lock is housed within a mortise cut into a door edge so that the lock mechanism is covered on both sides. 
  * Lock is concealed except for a faceplate at the door edge, knobs or levers, a cylinder, and operating trim. 
  * Backset: 2-½″ (64) for 1-⅜″ (35) doors; 2-¾″ (70) for 1-¾″ (45) doors

### **Unit and Integral Locks**

  * Unit lock is housed within a rectangular notch cut into the edge of a door. 
  * Integral lock fits into a mortise cut into the edge of a door. 
  * Unit and integral locks combine the security advantages of a mortise lock with the economy of a cylinder lock. 
  * Backset: 2-¾″ (70) for unit locks; 2-¼″ (57) for integral locks

### **Cylinder Lock**

  * Cylinder lock is housed within two holes bored at right angles to each other, one through the lock stile of a door and the other in the door edge. 
  * Cylinder locks are relatively inexpensive and easy to install. 
  * Backset: 2-⅜″ (60) for standard locksets; 2-¾″ (70) for heavy-duty locksets

### **Door Knobs**

  * Rose refers to a round or square ornamental plate surrounding the shaft of a doorknob at the face of a door. 
  * Escutcheon is a protective or ornamental plate that may be substituted for a rose. 

### **Lever Handles**

  * Lever-operated mechanisms, push-type mechanisms, and U-shaped handles are generally easier for people with disabilities to grasp. 

### **Pull Handles and Push Plates**

### **ADA Accessibility Guidelines**

  * Door handles, pulls, latches, and locks should be easy to grasp with one hand without tight grasping, pinching, or twisting of the wrist. 
  * The force required for pushing open or pulling open a door should be no greater than 5.0 lbs. ( 22.2 N). 

## **8.20 PANIC HARDWARE & CLOSERS**

### **Panic Hardware**

Panic hardware is a door-latching assembly that disengages when pressure is applied on a horizontal bar that spans the interior of an emergency exit door at waist height.  The push bar should extend across at least one-half the width of the door leaf on which it is installed. 

  * Building codes require the use of panic hardware on emergency egress doors in certain building occupancies.  Consult the applicable building code for details. 

### **Exposed Vertical Rod**

### **Concealed Lateral Latching**

### **ADA Accessibility Guideline**

  * The force required for pushing open or pulling open a door should be no greater than 5.0 lbs. ( 22.2 N). 

### **Door Closers**

Door closers are hydraulic or pneumatic devices that automatically close doors quickly but quietly.  They help reduce the shock a large, heavy, or heavily used door would otherwise transmit upon closing to its frame, hardware, and surrounding wall. 

  * Building codes require the use of self-latching, self-closing doors with UL-rated hardware to protect openings in fire walls and occupancy separations; see 2.07. 

**CSI MasterFormat 08 71 00: Door Hardware**

## **8.21 WEATHERSTRIPPING & THRESHOLDS**

### **Weatherstripping**

Weatherstripping consists of metal, felt, vinyl, or foam rubber strips, placed between a door or window sash and its frame, to provide a seal against windblown rain and reduce the infiltration of air and dust. 

  * Weatherstripping may be fastened to the edge or face of a door, or to the doorframe and threshold. 
  * The weatherstripping material should be durable under extended use, noncorrosive, and replaceable. 
  * Basic types of weatherstripping include:
  * Spring-tensioned strip of aluminum, bronze, or stainless or galvanized steel
  * Vinyl or neoprene gaskets
  * Foam plastic or rubber strips
  * Woven pile strips

### **Weatherstripping Door Jambs**

  * Metal spring strip

  * Foam rubber or felt

  * Vinyl or rubber

### **Weatherstripping Meeting Stiles**

  * Metal spring strip

  * Vinyl gasket

  * Vinyl gasket

### **Weatherstripping Door Thresholds**

  * Vinyl gasket

  * Vinyl gasket

  * Applied sweep

  * Bumperstrip

  * Interlocking J-hook

  * Vinyl insert

### **Thresholds**

Thresholds cover the joints between two flooring materials at doorways and serve as a weather barrier at exterior sills. 

  * Metal thresholds may be cast or covered with abrasive material to provide a non-slip surface. 

### **ADA Accessibility Guideline**

## **8.22 WINDOW ELEMENTS**

### **Building Code Requirements**

In selecting a window unit, review the building code requirements for:

  * Natural light and ventilation of habitable spaces
  * Thermal insulation value of the window assembly
  * Structural resistance to wind loads
  * Clear opening of any operable window that serves as an emergency exit for a residential sleeping space; such windows are typically required to be at least 5.7 sf (0.53 m2) in area and have a minimum clear width of 20″ (510), a minimum clear height of 24″ (610), and a sill no higher than 44″ (1120) above the floor. 
  * Safety glazing for a window that could be mistaken for an open doorway; any window that is more than 9 sf (0.84 m2) and within 24″ (610) of a doorway or less than 60″ (1525) above the floor be safety glazed with tempered glass, laminated glass, or plastic. 
  * Type and size of glazing allowable in fire-rated walls and corridors. 

## **8.23 WINDOW OPERATION**

### **Fixed**

  * 0% ventilating

  * Fixed windows consist of a frame and stationary sash. 
  * When used in conjunction with operable window units, the thickness of the fixed sash should approximate the cross-sectional dimension of the operating sashes. 

### **Casement**

  * 100% ventilating

  * Casement windows have operating sashes that are side-hinged and usually swing outward. 
  * When open, the sash is able to direct ventilation. 
  * The inner end of the sash may slide along a track on the sill or jamb as the sash swings outward. 
  * A pair of sashes may close on a vertical mullion or have a floating astragal to close on each other. 

### **Awning & Hopper**

  * 100% ventilating

  * Awning windows have operating sashes that swing outward on hinges attached to the top of their frames. 
  * Hopper windows have operating sashes that swing inward on hinges attached to the bottom of their frames. 
  * When open, the sash is able to direct ventilation. 
  * The sashes may be stacked vertically with sashes closing on each other or on meeting stiles. 

LEED® EQ Credit 2: Increased Ventilation  
LEED EQ Credit 8: Daylight & Views

### **Sliding**

  * 50% ventilating

  * A sliding window has two or more sashes, of which at least one slides along horizontal grooves or tracks. 

### **Double-Hung**

  * 50% ventilating

  * Double-hung windows have two vertically sliding sashes, each in separate grooves or tracks, closing different parts of the window. 
  * The sashes are held in the desired position by means of counterweights, pretensioned springs, or friction. 
  * Single-hung windows have two sashes, of which only one is movable. 

### **Jalousie**

  * 100% ventilating

  * Jalousie windows have horizontal glass or wood louvers that pivot simultaneously in a common frame. 
  * Jalousies are used primarily in mild climates to control ventilation and to cut off visibility from the outside. 

### **Pivoting**

  * 100% ventilating

  * Pivoting windows have sashes that rotate 90° or 180° about a vertical or horizontal axis at or near their centers. 
  * Pivoting sashes are used in air-conditioned multistory or high-rise buildings and operated only for cleaning, maintenance, or emergency ventilation. 

## **8.24 METAL WINDOWS**

Metal windows may be fabricated and of aluminum, steel, or bronze.  Shown on this and the following page are typical sections for aluminum windows and steel windows.  Because window frame and sash sections vary greatly from one manufacturer to the next, refer to the manufacturer's literature for:

  * Large-scale details of frame and sash profiles
  * Alloy, weight, and thickness of sections
  * Thermal performance of window assembly
  * Resistance to corrosion, water pressure, air infiltration, and wind loading
  * Glazing methods and options
  * Finishes available
  * Rough or masonry openings required; some manufacturers offer stock window sizes while others will fabricate custom sizes, shapes, and configurations. 

### **Aluminum Windows**

Aluminum window frames are relatively low in cost, lightweight, and corrosion resistant, but because they are such efficient conductors of heat, synthetic rubber or plastic thermal breaks are required to interrupt the flow of heat from the warm to the cool side of the frame.  Aluminum frames may have anodized, baked enamel, or fluoropolymer resin finishes. 

Consult the American Architectural Manufacturers Association (AAMA) for criteria developed for the performance of aluminum windows, including minimum provisions for frame strength and thickness, corrosion resistance, air infiltration, water resistance, and wind load capability. 

**CSI MasterFormat 08 51 00: Metal Windows**

## **8.25 METAL WINDOWS**

### **Steel Windows**

Steel window frame and sash sections are manufactured from hot-rolled or cold-rolled steel.  Because steel is stronger than aluminum, these sections are more rigid and thinner in profile than aluminum sections, offer narrower sightlines, and allow larger lights to be installed in a given rough or masonry opening.  Steel also has a lower coefficient of heat transfer than aluminum and therefore steel window frames do not normally require thermal breaks. 

The frame and sash sections are welded together and are usually galvanized or bonderized and primed for painting.  Baked acrylic enamel, urethane, and polyvinyl chloride (PVC) finishes are also available. 

Consult the Steel Window Institute (SWI) for the criteria and standards established for various weights of steel window frames and sashes. 

## **8.26 WOOD WINDOWS**

Wood frames are thicker than aluminum or steel frames, but they are also more effective as thermal insulators.  The frames are usually of kiln-dried, clear, straight-grain wood, factory-treated with a water-repellant preservative.  The wood may be stained, painted, or primed for painting on site.  To minimize the need for maintenance, the majority of wood frames are now clad with vinyl or bonded to acrylic-coated aluminum sections that require no painting. 

Most stock wood windows are manufactured according to standards established by the National Wood Window and Door Association (NWWDA) and adopted by the American National Standards Institute (ANSI).  The exact profile and dimensions of the window frame and sash vary with the type of window operation and from manufacturer to manufacturer.  Each manufacturer, however, usually has large-scale 1-½″ or 3″ = 1′-0″ (1:10 or 1:5) details that can be used to work out specific window installations. 

  * Consult window manufacturer for stock window sizes and rough openings required.  Some manufacturers will fabricate custom sizes, shapes, and configurations. 

Window manufacturers offer various combinations of both fixed and venting units to cover large openings. 

  * Window units may be stacked vertically or be banked side by side. 

  * Special shapes are available from many manufacturers. 
  * Angled or box bay windows

**CSI 08600: Wood Windows**

## **8.27 WOOD WINDOWS**

## **8.28 GLAZING SYSTEMS**

### **Face Glazing**

Small glass panes may be set in a rabbeted frame, held in place with glazier's points, and sealed with a beveled bead of putty or glazing compound. 

  * Putty is a compound of whiting and linseed oil, of doughlike consistency when fresh, used in securing windowpanes or patching woodwork defects. 
  * Glazing compound is an adhesive compound used as putty, formulated so as not to become brittle with age. 

Lights more than 6 sf (0.56 m2) in area, must be wet- or dry-glazed. 

### **Wet Glazing**

Wet glazing is the setting of glass in a window frame with glazing tape or a liquid sealant. 

### **Dry Glazing**

Dry glazing is the setting of glass in a window frame with a compression gasket instead of glazing tape or a liquid sealant. 

### **Structural Gaskets**

Structural gaskets are preformed of synthetic rubber or other elastomeric material to secure a glass pane or unit in a window frame or opening.  The gaskets are held in compression by forcing a keyed locking strip into a groove in the gasket.  They require smooth contact surfaces and a frame or opening with exacting dimensional tolerances and true plane alignment.  The glass must be supported on at least two sides by the frame or a supported gasket. 

**CSI MasterFormat 08 81 00: Glass Glazing**

## **8.29 GLAZING SYSTEMS**

Both wet- and dry-glazing systems should allow the glass unit to float in its opening and be cushioned with a resilient glazing material.  There should be no direct contact between the glass and the perimeter frame.  The perimeter frame itself must support the glass against wind pressure or suction, and be strong enough that structural movements and thermal stresses are not transferred to the glass. 

## **8.30 INSULATING GLASS**

Insulating glass consists of two or more sheets of glass separated by a hermetically sealed air space to provide increased thermal insulation and restrict condensation. 

## **8.31 GLAZED CURTAIN WALLS**

Glazed curtain walls are exterior nonloadbearing walls consisting of vision glass or opaque spandrel panels supported by metal framing.  They may be categorized according to their method of assembly. 

### **Stick Systems**

The stick system consists of tubular metal mullions and rails assembled piece by piece on site to frame vision glass and spandrel units.  It offers relatively low shipping and handling costs and can be adjusted more readily than other systems to on-site conditions. 

### **Unit Systems**

Unit systems consist of preassembled, framed wall units which may be preglazed or glazed after installation.  Shipping bulk is greater than with the stick system, but less field labor and erection time is required. 

### **Unit-and-Mullion Systems**

In the unit-and-mullion system, one- or two-story-high mullions are installed before preassembled wall units are lowered into place behind the mullions.  The panel units may be full-story height, preglazed or unglazed, or may be separate vision glass and spandrel units. 

### **Column-Cover-and-Spandrel Systems**

Column-cover-and-spandrel systems consist of vision-glass assemblies and spandrel units supported by spandrel beams between exterior columns clad with cover sections. 

  * See 7.24–7.26 for general conditions and requirements of curtain wall construction. 

**CSI MasterFormat 08 44 00: Curtain Wall and Glazed Assemblies**

## **8.32 GLAZED CURTAIN WALLS**

These details illustrate typical conditions of glazed curtain wall construction.  When using standard fabricated wall systems, there is no need for extensive detailing except when components are modified.  For more in-depth information, refer to the Aluminum Curtain Wall Design Guide Manual, published by the American Architectural Manufacturers Association (AAMA), the Flat Glass Marketing Association (FGMA), and standards developed by the American Society for Testing and Materials (ASTM).  Things to note include:

  * Overall wall pattern
  * Type of glazing
  * Type, size, and location of any operable window sash
  * Type and finish of infill or spandrel panels
  * Perimeter, corner, and anchorage conditions

## **8.33 GLAZED CURTAIN WALLS**

A curtain wall system may utilize structural gaskets to glaze both fixed glass units and spandrel panels.  The supporting frame members should be of the same thickness as the insulating glass unit to ensure balanced support. 

When stacking insulating glass units vertically, the weight of the upper glass units can introduce stresses into the lower glass units.  For this reason, the horizontal mullion rather than the gaskets should provide the necessary support for the glazing. 

See 8.28 for more information on glazing with structural gaskets. 

### **Flush Glazing**

Flush glazing is a glazing system in which the metal framing members are set entirely behind the glass panes or units to form a flush exterior surface.  The glass units adhere to the framing with a structural silicone sealant; the silicone sealant transfers wind and other loads from the glass to the metal curtain wall frame without mechanical fastenings.  The design should allow for easy maintenance and replacement of broken glass units.  Factory-glazing is preferred for better quality control.  Consult manufacturer for details. 

## **8.34 GLAZED CURTAIN WALLS**

### **Channel Glass**

Channel glass is cast by drawing molten glass over a series of steel rollers to form a continuous flat U-shape, which is cut to specified length after cooling.  The translucent channel sections are available in widths from 9″ to 19″ (230 to 480) and in lengths up to 23 feet (7010).  For exterior applications, the channel sections have 2-⅜″ (60) flanges and come in three standard widths, 9″ (230), 10-5/16″ (260), and 13″ (330). 

The thermal performance of channel glass can be enhanced with a low-e coating applied directly to the inside face of the glass.  When greater performance is required a thermal insulating material can be inserted into the cavity of a double-glazed wall system, bringing down the U-value of the system to as low as 0.19. 

Channel glass is suitable for interior and exterior applications.  For exterior applications, channel glass systems can be constructed as double-glazed curtain walls and store fronts or as single-glazed rain screens and trombe walls. 

The self-supporting sections may be installed vertically or horizontally within extruded aluminum perimeter frames.  Vertical systems are site-built while horizontal systems are usually pre-assembled for better quality control and to shorten the project construction schedule. 

LEED EA Credit 1: Optimize Energy Performance  
LEED IEQ Credits 6 & 7: Controllability of Systems & Thermal Comfort

**CSI MasterFormat 08 44 00: Curtain Wall and Glazed Assemblies**

## **8.35 DOUBLE-SKIN FACADES**

Double-skin facades, also known as smart facades, refer to cladding systems designed to conserve and reduce the energy needed for heating, cooling, and lighting a building by integrating passive solar collection, solar shading, daylighting, thermal resistance, and natural ventilation into its assembly.  The assembly usually consists of a double- or triple-glazed unit on the interior, an air space for harvesting heat and containing adjustable shading devices to control solar radiation and daylighting, and an exterior layer of safety or laminated glazing with operable panels and sometimes energy-generating photovoltaic technologies. 

## **8.36 SKYLIGHTS**

Glazed openings in a roof allow daylight to enter an interior space from above.  This efficient and cost-effective source of lighting can be in place of or in addition to the normal daylighting from windows.  Careful consideration, however, should be paid to the control of brightness and glare, which may require the use of louvers, shades, or reflector panels.  Horizontal and south-facing skylights also increase solar heat gain in the winter, but in the summer, shading may again be required to prevent excessive heat gain. 

Glazed openings may be constructed using the following elements:

  * Skylights are metal-framed units preassembled with glass or plastic glazing and flashing.  They are available in stock sizes and shapes but may also be custom-fabricated. 

  * Vault

  * Ridge

  * Hipped

  * Circular Dome

  * Square dome

  * Pyramid

  * Roof windows are stock wood windows designed for installation in a sloping roof.  These windows either pivot or swing open for ventilation and cleaning.  They are typically 2′ to 4′ (610 to 1220) wide and 3′ to 6′ high (915 to 1830) and available with shades, blinds, and electric operators. 

### **Skylight Forms**

  * Skylights set at an angle of less than 45° require a curb at least 4″ (100) high to elevate the skylight above the surrounding roof surface.  This curb may be job-built or be an integral part of the skylight unit. 

**CSI MasterFormat 08 61 00: Roof Windows  
CSI MasterFormat 08 62 00: Unit Skylights  
CSI MasterFormat 08 44 33: Sloped Glazing Assemblies**

## **8.37 SKYLIGHT DETAILS**

### **Typical Curb Detail**

### **Curb Types**

**Aluminum**

**Wood**

**Concrete**

## **8.38 SUNSPACES**

A sunspace is a glass-enclosed porch or room adjoining another living space and oriented to admit large amounts of sunlight.  Sunspaces are often used in passive solar design in conjunction with a thermal mass of masonry, rock, or concrete to store the solar heat gain.  Because of the possibility of overheating, provision should be made for shading and ventilation with operable windows and, if necessary, an exhaust fan. 

  * Sunspaces, solariums, and greenhouses are available as manufactured systems with wood or metal frames, complete with glazing and flashing. 
  * A ventilating fan can be mounted on the roof or in either of the gable ends. 
  * Insulating shades and blinds follow the slope of the roof and can be operated manually or by remote control. 
  * French or sliding doors can be located in either of the gable ends. 
  * Awning and casement sashes for ventilation are available for the front and side walls; some systems offer ventilating roof sashes. 

  * The details in the lower half of 8.37 characterize the construction of metal-framed glazed structures.  Shown below are typical details for a wood-framed sunspace or solarium. 

**CSI MasterFormat 13 34 13: Glazed Structures**

# **Chapter 9**  
 **SPECIAL CONSTRUCTION**

9.02 Special Construction

9.03 Stair Design

9.04 Stair Requirements

9.06 Stair Plans

9.08 Wood Stairs

9.10 Concrete Stairs

9.11 Steel Stairs

9.12 Spiral Stairs

9.13 Ladders

9.14 Elevators

9.17 Escalators

9.18 Fireplaces

9.19 Fireplace Requirements

9.20 Masonry Chimneys

9.21 Prefabricated Fireplaces & Stoves

9.22 Kitchen Layouts

9.23 Kitchen Dimensions

9.24 Kitchen Cabinets

9.25 The Kitchen Space

9.26 Bathroom Layouts

9.27 Plumbing Fixtures

9.28 Accessible Fixtures

9.30 The Bathroom Space

## **9.02 SPECIAL CONSTRUCTION**

This chapter discusses those elements of a building that have unique characteristics and that therefore should be considered as separate entities.  While not always affecting the exterior form of a building, they do influence the internal organization of spaces, the pattern of the structural system, and in some cases, the layout of heating, plumbing, and electrical systems. 

Stairs provide means for moving from one level to another and are therefore important links in the overall circulation scheme of a building.  Whether punctuating a two-story volume or rising through a narrow shaft, a stairway takes up a significant amount of space.  The landings of a stairway should be logically integrated with the structural system to avoid overly complicated framing conditions.  Safety and ease of travel are, in the end, the most important considerations in the design and placement of stairs. 

Multistory buildings require elevators to move people, equipment, and freight from one floor to another.  For accessibility to multistory public and commercial facilities by persons with disabilities, federal regulations mandate their installation.  An alternative to elevators is the escalator, which can move a large number of people efficiently and comfortably between a limited number of floors. 

Fireplaces and woodburning stoves are sources of heat and visual points of interest for any interior space.  The placement and size of a fireplace or stove in a room should be related to the scale and use of the space.  Both fireplaces and stoves must be located and constructed to draft properly.  The damper and flue sizes should correspond to the size and proportions of the firebox and precautions should be taken against fire hazards and heat loss. 

Kitchens and bathrooms are unique areas of a building that demand the careful integration of plumbing, electrical, and heating/ventilating systems with the functional and aesthetic requirements of the spaces.  These areas also require special fixtures and equipment, as well as durability, ease of maintenance, and sanitary surfaces and finishes. 

## **9.03 STAIR DESIGN**

The dimensions of risers and treads in a stairway should be proportioned to accommodate our body movement.  Their pitch, if steep, can make ascent physically tiring as well as psychologically forbidding, and can make descent precarious.  If the pitch of a stairway is shallow, its treads should be deep enough to fit our stride. 

Building codes regulate the minimum and maximum dimensions of risers and treads; see 9.04–9.05.  For comfort, the riser and tread dimensions can be proportioned according to either of the following formulas:

  * Tread (inches) + 2x riser (inches) = 24 to 25
  * Riser (inches) x tread (inches) = 72 to 75

Exterior stairs are generally not as steep as interior stairs, especially where dangerous conditions such as snow and ice exist.  The proportioning formula can therefore be adjusted to yield a sum of 26. 

For safety, all risers in a flight of stairs should be the same rise and all treads should have the same run.  Building codes limit the allowable variation in riser height or tread run to ⅜″ (9.5 mm).  Consult the building code to verify the dimensional guidelines outlined on this and the following page. 

  * The actual riser and tread dimensions for a set of stairs are determined by dividing the total rise or floor-to-floor height by the desired riser height.  The result is rounded off to arrive at a whole number of risers.  The total rise is then redivided by this whole number to arrive at the actual riser height. 
  * This riser height must be checked against the maximum riser height allowed by the building code.  If necessary, the number of risers can be increased by one and the actual riser height recalculated. 
  * Once the actual riser height is fixed, the tread run can be determined by using the riser:tread proportioning formula. 
  * Since in any flight of stairs, there is always one less tread than the number of risers, the total number of treads and the total run can be easily determined. 

## **9.04 STAIR REQUIREMENTS**

Stairway design is strictly regulated by the building code, especially when a stairway is an essential part of an emergency egress system.  Because an accessible stairway should also serve as a means of egress during an emergency, the ADA accessibility requirements illustrated on the next page are similar to those of an emergency egress stairway. 

## **9.05 STAIR REQUIREMENTS**

### **ADA Accessibility Guidelines**

Accessible stairs should also serve as a means of egress during an emergency, or lead to an accessible area of refuge where people who are unable to use stairs may remain temporarily in safety to await assistance during an emergency evacuation. 

### **Handrails**

  * Handrails should be free of sharp or abrasive elements and have a circular cross section with an outside diameter of 1-¼″ (32) minimum and 2″ (51) maximum; other shapes are allowable if they provide equivalent graspability and have a maximum cross-sectional dimension of 2-¼″ (57). 

  * 1-½″ (38) minimum clearance between handrail and wall

### **Ramps**

Ramps provide smooth transitions between the floor levels of a building.  To have comfortable low slopes, they require relatively long runs.  They are typically used to accommodate a change in level along an accessible route or to provide access for wheeled equipment.  Short, straight ramps act as beams and may be constructed as wood, steel, or concrete floor systems.  Long or curvilinear ramps are usually of steel or reinforced concrete. 

### **Landings**

### **Handrails**

## **9.06 STAIR PLANS**

### **Straight-Run Stair**

  * A straight-run stair extends from one level to another without turns or winders. 
  * Building codes generally limit the vertical rise between landings to 12′ (3660). 

  * A stairway may be approached or departed either axially or perpendicular to the stair run. 

### **Quarter-Turn Stair**

  * A quarter-turn or L-shaped stair makes a right-angled turn in the path of travel. 
  * The two flights connected by an intervening landing may be equal or unequal, depending on the desired proportion of the stairway opening. 

  * Landings that are below normal eye level and provide a place to rest or pause are inviting. 

### **Half-Turn Stair**

  * A half-turn stair turns 180° or through two right angles at an intervening landing. 
  * A half-return stair is more compact than a single straight-run stair. 
  * The two flights connected by the landing may be equal or unequal, depending on the desired proportion of the stairway opening. 

## **9.07 STAIR PLANS**

### **Winding Stair**

  * A winding stair is any stairway constructed with winders, as a circular or spiral stair.  Quarter-turn and half-turn stairs may also use winders rather than a landing to conserve space when changing direction. 
  * Winders can be hazardous since they offer little foothold at their interior corners.  Building codes generally restrict the use of winders to private stairs within individual dwelling units. 

### **Circular Stair**

  * A circular stair, as its name implies, has a circular plan configuration.  Even though a circular stair is constructed with winders, the building code may allow its use as part of the means of egress from a building if its inner radius is at least twice the actual width of the stairway. 

### **Spiral Stair**

  * A spiral stair consists of wedge-shaped treads winding around and supported by a central post. 
  * Spiral stairs occupy a minimum amount of floor space, but building codes permit their use only as private stairs in individual dwelling units. 
  * See 9.12 for typical dimensions. 

## **9.08 WOOD STAIRS**

A wood stair is constructed of the following elements:

**CSI MasterFormat™ 06 43 00: Wood Stairs and Railings**

## **9.09 WOOD STAIRS**

  * Open-riser stairs do not comply with ADA accessibility guidelines. 

## **9.10 CONCRETE STAIRS**

A concrete stair is designed as an inclined, one-way reinforced slab with steps formed on its upper surface.  If the stair is constructed after the floor beam or wall supports, it acts as a simple beam.  If it is cast with the beam or slab supports, it is designed as a continuous beam.  Concrete stairs require careful analysis of load, span, and support conditions; consult a structural engineer for final design requirements. 

### **Longitudinal Section**

**CSI MasterFormat 03 30 00: Cast-in-place Concrete  
CSI MasterFormat 03 11 23: Permanent Stair Forming**

## **9.11 STEEL STAIRS**

Steel stairs are analogous in form to wood stairs. 

**CSI MasterFormat 05 51 00: Metal Stairs**

## **9.12 SPIRAL STAIRS**

### **Plan and Elevation**

### **Stair Connections**

### **Stair Treads**

### **Representative Sizes and Dimensions of Spiral Stairs***

**CSI MasterFormat 05 71 13: Fabricated Metal Spiral Stairs**

## **9.13 LADDERS**

Ladders are used primarily in industrial construction and in utility and service areas.  They may also be used in private residential construction where space is extremely tight and traffic is minimal. 

The drawings on this page illustrate ladders built with metal components.  The ladder forms may be translated into wood construction. 

Safety considerations include:

  * Proper riser height
  * Adequate toe space
  * Adequate support for strings and railings
  * Slip-resistant treads

### **Ship's Ladder**

### **Vertical Ladders**

**CSI MasterFormat 05 51 33: Metal Ladders**

## **9.14 ELEVATORS**

Elevators travel vertically to carry passengers, equipment, and freight from one level of a building to another.  The two most common types are electric elevators and hydraulic elevators. 

### **Electric Elevators**

Electric elevators consist of a car that is mounted on guide rails, supported by hoisting cables, and driven by electric hoisting machinery in a penthouse.  Geared traction elevators are capable of speeds up to 350 fpm (1.75 m/s) and are suitable for medium-rise buildings.  Gearless traction elevators are available with speeds up to 1200 fpm (6 m/s) and typically serve high-rise buildings. 

**CSI MasterFormat 14 20 00: Elevators**

## **9.15 ELEVATORS**

### **Hydraulic Elevators**

Hydraulic elevators consist of a car supported by a piston that is moved by or moves against a fluid under pressure.  A penthouse is not required, but the hydraulic elevator's lower speed and piston length limit its use to buildings up to six stories in height. 

### **Elevator Car Dimensions**

### **Limited Use/Limited Access Elevators**

Limited Use/Limited Access (LU/LA) elevators are small hydraulic elevators designed for installation in new or existing low-rise structures.  LU/LA elevators are limited to 25′ (7620) of travel at a speed of 30 fpm (0.55 km/h), a load capacity of 1400 lb. ( 635 kg), and a cab floor area of 18 sf (1.67 m2).  They can operate on single-phase power and require less pit depth and overhead space than do regular commercial elevators. 

## **9.16 ELEVATORS**

### **Elevator Layout**

The type, size, number, speed, and arrangement of elevators are determined by:

  * Type of occupancy
  * Amount and tempo of traffic to be carried
  * Total vertical distance of travel
  * Round-trip time and speed desired

  * Consult elevator manufacturer for recommended type, size, layout, controls, and installation requirements and details. 
  * Consult the building code for structural requirements and shaftway requirements for fire separation, ventilation, and soundproofing. 

### **ADA Accessibility Guidelines**

## **9.17 ESCALATORS**

Escalators are power-driven stairways consisting of steps attached to a continuously circulating belt.  They can move a large number of people efficiently and comfortably between a limited number of floors; six floors are a practical limit.  Because escalators move at a constant speed, there is practically no waiting period, but there should be adequate queuing space at each loading and discharge point.  Escalators may not be used as required fire exits. 

  * Moving sidewalks are power-driven, continuously moving surfaces, similar to a conveyor belt, used for carrying pedestrians horizontally or along low inclines. 

**CSI MasterFormat 14 30 00: Escalators and Moving Walks**

## **9.18 FIREPLACES**

A fireplace is a framed opening in a chimney to hold an open fire.  It must be designed and constructed to:

  * Sustain the combustion of fuel;
  * Draw properly to carry smoke and other combustive by-products to the outside;
  * Radiate the maximum amount of heat comfortably into the room;
  * Ensure proper distances from combustible materials. 

Thus the dimensions and proportions of a fireplace and its flue and the arrangement of its components, are subject to the laws of nature and the requirements of the building and mechanical codes.  The table below provides typical dimensions for three types of fireplaces.  See facing page for key to letter heads (A) through (G). 

### **Types of Fireplaces**

**Open Front**

**Open Front and Side**

**Open Front and Back**

### **Typical Fireplace Dimensions in Inches (mm)**

**CSI MasterFormat 04 57 00: Masonry Fireplaces**

## **9.19 FIREPLACE REQUIREMENTS**

### **Fireplace Plan**

### **Fireplace Elevation**

  * For typical fireplace dimensions, see table on previous page. 

### **Fireplace Section**

## **9.20 MASONRY CHIMNEYS**

**Minimum Flue Sizes**

  * Square or rectangular: 1/10th of fireplace opening
  * Round: 1/12th of fireplace opening

  * Flue linings are smooth-surfaced units of heat-resistant fire clay or lightweight concrete. 

  * Rectangular flues
  * Size = outside faces

  * Modular flues
  * Size = actual + ½″ (13)

  * Round flues
  * Size = inside ø

### **Chimney Hood**

  * Consult building or mechanical code for chimney requirements of high heat appliances such as incinerators. 

  * In certain seismic zones, masonry chimneys require reinforcement and anchorage to the structural frame of a building.  Consult the building code for detail requirements. 

### **Typical Flue Dimensions and Areas**

**CSI MasterFormat 04 51 00: Flue Liner Masonry**

## **9.21 PREFABRICATED FIREPLACES & STOVES**

Prefabricated fireplaces and woodburning stoves should be certified by the Environmental Protection Agency (EPA) for burning efficiency and allowable particulate emissions. 

### **Prefabricated Fireplaces**

  * Typical widths: 36″, 38″, 46″, 48″, 54″ (915, 965, 1170, 1220, 1370)
  * Typical heights: 30″, 32″, 36″ (760, 815, 915)
  * Typical depth: 24″ (610)

### **Woodburning Stoves**

**CSI MasterFormat 10 31 00: Manufactured Fireplaces  
CSI MasterFormat 10 35 00: Stoves**

## **9.22 KITCHEN LAYOUTS**

These plans illustrate the basic types of kitchen layouts.  They can be readily adapted to various structural or spatial situations, but they are all based on a work triangle that connects the three major kitchen centers:

(A) Refrigerator center for receiving and preparing food

(B) Sink center for food preparation and clean up

(C) Range center for cooking and serving

The sum of the sides of the triangle should be not more than 22′ (6705) nor less than 12′ (3660). 

### **Parallel Walls**

Additional factors to consider in laying out a kitchen space include:

  * Amount of counter space and work surfaces required
  * Type and quantity of under-counter and overhead storage required
  * Requirements for natural light, views, and ventilation
  * Type and degree of access desired
  * Degree of enclosure envisioned for the space
  * Integration of electrical, plumbing, and mechanical systems

### **L-Shape**

### **U-Shape**

### **Single Wall**

### **ADA Accessibility Guidelines**

## **9.23 KITCHEN DIMENSIONS**

### **Appliances**

Verify appliance dimensions when planning a kitchen layout.  For preliminary planning purposes, the following range of widths can be used:

  * Range: 33″ to 40″ (840 to 1015)
  * Refrigerator: 32″ to 36″ (815 to 915)
  * Dishwasher: 24″ (610)
  * Sink: 32″ to 42″ (815 to 1065)

  * Countertop dimensions should be coordinated with standard cabinet sizes; see 9.24. 

### **ADA Accessibility Guidelines**

## **9.24 KITCHEN CABINETS**

Kitchen cabinets may be constructed of wood or enameled steel.  Wood cabinets usually have hardwood frames and plywood or particle board panels with plastic laminate, hardwood veneer, or lacquer finishes. 

Stock kitchen cabinets are manufactured in 3″ (75) modules and should conform to standards established by the National Kitchen Cabinet Association (NKCA).  There are three basic types of units: base units, wall units, and special units.  Consult manufacturer for available sizes, finishes, hardware, and accessories. 

### **Basic Wall Unit**

  * 24″ to 48″ (610 to 1220) long in 3″ (75) increments
  * 12″ to 33″ (305 to 840) high

### **Combination Wall Unit**

  * For use over sinks and ranges
  * 60″ to 84″ (1525 to 2135) long
  * 30″ (760) high

### **Sink Base Unit**

  * 54″ to 84″ (1370 to 2135) long in 3″ (75) increments

### **Drawer Unit**

  * 15″ to 24″ (380 to 610) wide

### **Basic Base Unit**

  * 12″ to 24″ (305 to 610) wide for one-door units
  * 27″ to 48″ (685 to 1220) wide for two-door units
  * 23″ or 24″ (585 or 610) deep

  * 34-½″ (875) height of base units allows for countertops up to 1-½″ (38) thick. 

  * Base units for bathroom vanities are 30″ (760) high and 21″ (535) deep. 
  * Base units for buffets and desks are 28-½″ (725) high. 

### **Wall Oven Unit**

  * 18″ to 30″ (455 to 760) wide
  * 84″ (2135) tall

### **Utility Closet or Pantry Unit**

  * 12″ and 24″ (305 and 610) depths

### **Base Corner Unit**

  * 39″ to 48″ (990 to 1220) long

### **Base Corner Unit**

  * 36″ (915) long

  * Finished end and filler panels are available. 

**CSI MasterFormat 12 35 30.13: Kitchen Casework**

## **9.25 THE KITCHEN SPACE**

## **9.26 BATHROOM LAYOUTS**

These bathroom plans illustrate basic layouts and relationships, which can be adjusted to suit specific situations.  Fixture spacing and clearances are important for safe and comfortable movement within a bathroom space.  Recommended dimensions can be perceived through the study of these plans and the drawings on the facing page.  The overall dimensions of a bathroom will vary according to the actual sizes of the fixtures used. 

The layout of bathrooms and other restroom facilities should also take into account the

  * Space for and locations of accessories such as towel bars, mirrors, and medicine cabinets
  * Number of plumbing walls required and the location of stacks, vents, and horizontal runs. 

### **ADA Accessibility Guidelines**

  * The clear floor spaces at fixtures, the accessible route, and the wheelchair turning space are permitted to overlap. 
  * See 9.28–9.29 for accessible fixture requirements. 
  * See A.03 for general ADA accessibility guidelines. 

## **9.27 PLUMBING FIXTURES**

The range of fixture dimensions given below is for preliminary planning purposes only.  Consult the fixture manufacturer for actual dimensions of specific models. 

Plumbing fixtures may be made of the following materials. 

  * Water closets, urinals, and bidets: vitreous china
  * Lavatories, bathtubs, and utility sinks: vitreous china, enameled cast iron, enameled steel
  * Shower receptacles: terrazzo, enameled steel
  * Shower enclosures: enameled steel, stainless steel, ceramic tile, fiberglass
  * kitchen sinks: enameled cast iron, enameled steel, stainless steel

### **Fixture Clearances**

**Water Closet**

**Lavatory**

**Bathtub**

## **9.28 ACCESSIBLE FIXTURES**

### **Bathtubs**

  * Diameter or width of grab bars should be 1-¼″ to 1-½″ (32 to 38) with a 1-½″ (38) space between the grab bar and the wall. 

### **Shower Stalls**

### **Lavatories and Sinks**

**CSI MasterFormat 10 28 16: Bath Accessories**

## **9.29 ACCESSIBLE FIXTURES**

### **Water Closets**

### **Toilet Stalls**

  * Grab bars should be mounted in a horizontal position 33″ to 36″ (840 to 915) above the floor, on the rear wall and on the side wall closest to the water closet. 

**CSI MasterFormat 10 21 13: Toilet Compartments**

## **9.30 THE BATHROOM SPACE**

**CSI MasterFormat 12 35 30.23: Bathroom Casework**

# **Chapter 10**  
 **FINISH WORK**

10.02 Finish Work

10.03 Plaster

10.04 Plaster Lath & Accessories

10.05 Plaster Partition Systems

10.06 Plaster Details

10.07 Plaster over Masonry

10.08 Plaster Ceilings

10.09 Gypsum Board

10.11 Gypsum Board Details

10.12 Ceramic Tile

10.13 Ceramic Tile Applications

10.14 Ceramic Tile Details

10.15 Terrazzo Flooring

10.16 Wood Flooring

10.17 Wood Flooring Installation

10.18 Stone Flooring

10.19 Resilient flooring

10.20 Carpeting

10.22 Acoustical Ceiling Tiles

10.23 Suspended Acoustical Ceilings

10.24 Wood Joints

10.26 Wood Moldings & Trim

10.28 Wood Paneling

10.29 Plywood Veneer

10.30 Plastic Laminate

## **10.02 FINISH WORK**

This chapter illustrates the major materials and methods used to finish the interior wall, ceiling, and floor surfaces of a building.  Interior walls should be resistant to wear and be cleanable; floors should be durable, comfortable, and safe to walk on; ceilings should be relatively maintenance-free. 

Because exterior wall surfaces, such as stucco and wood siding, must serve effectively as barriers against the penetration of water into the interior of a building, they are covered in Chapter 7 along with roof coverings. 

Rigid finish materials capable of spanning short distances may be applied to a supporting grid of linear members.  More flexible finish materials, on the other hand, require a solid, rigid backing.  Additional technical factors to consider include the acoustic qualities, fire resistance, and thermal insulation value of a finish material. 

Surface finishes have a critical influence on the aesthetic qualities of a space.  In the selection and use of a finish material, we should carefully consider its color, texture, and pattern, and the way it meets and joins with other materials.  If a finish material has modular characteristics, then its unit dimensions can be used to regulate the dimensions of a wall, floor, or ceiling surface. 

LEED EQ Credit 4: Low-Emitting Materials

## **10.03 PLASTER**

Plaster refers to any of various mixtures applied in a pasty form to the surfaces of walls or ceilings in a plastic state and allowed to harden and dry.  The most common type of plaster used in construction is gypsum plaster, which is made by mixing calcined gypsum with water, fine sand or lightweight aggregate, and various additives to control its setting and working qualities.  Gypsum plaster is a durable, relatively lightweight, and fire-resistant material that can be used on any wall or ceiling surface that is not subject to moist or wet conditions.  Portland cement plaster, also known as stucco, is used on exterior walls and in areas subject to wet or moist conditions; see 7.36. 

## **10.04 PLASTER LATH & ACCESSORIES**

### **Metal Lath**

Metal lath is a plaster base fabricated of expanded metal or of wire fabric, galvanized or coated with a rust-inhibiting paint for corrosion resistance. 

  * The weight and strength of the metal lath used is related to the spacing and rigidity of its supports. 
  * Expanded metal lath is fabricated by slitting and expanding a sheet of steel alloy to form a stiff network with diamond-shaped openings. 

  * Rib lath is an expanded-metal lath having V-shaped ribs to provide greater stiffness and permit wider spacing of the supporting framing members. 

  * Self-centering lath is a rib lath used over steel joists as formwork for concrete slabs, or as lathing in solid plaster partitions. 
  * Self-furring lath is expanded-metal, welded-wire, or woven-wire lath that is dimpled to space itself from the supporting surface, creating a space for the keying of plaster or stucco. 

  * Paper-backed lath is expanded-metal or wire lath having a backing of perforated or building paper, used as a base for ceramic tile and exterior stucco walls. 

### **Gypsum Lath**

Gypsum lath is a panel having an air-entrained core of hardened gypsum plaster faced with fibrous, absorbent paper to which plaster adheres. 

  * Perforated gypsum lath is punched with ¾″ (19) ø holes @ 4″ (100) o.c.  to provide a mechanical key for the plaster. 
  * Insulating gypsum lath has an aluminum foil backing that serves as a vapor retarder and reflective thermal insulator. 
  * Type X lath has glass fibers and other additives for greater fire resistance. 
  * Veneer base is a gypsum lath having a special paper facing for receiving veneer plaster. 

### **Trim Accessories**

Various accessories made of galvanized steel or zinc alloy are used to protect and reinforce the edges and corners of plaster surfaces.  These trim accessories also serve as grounds that help the plasterer level the finish coat and bring it up to the proper thickness.  For this reason, all grounds should be securely fastened to their supports and installed straight, level, and plumb.  Wood grounds may be used where a nailable base is required for the addition of wood trim. 

**CSI MasterFormat 09 22 36: Lath**

## **10.05 PLASTER PARTITION SYSTEMS**

### **Plaster over Metal Lath**

  * Three-coat plaster is applied over metal lath. 
  * Wood or metal studs are spaced 16″ or 24″ (405 or 610) o.c.,  depending on the weight of metal lath used; see table on 10.04.  The frame should be sturdy, rigid, plane, and level; deflection should be limited to 1/360th of the support spacing. 
  * The long dimension or ribs of the lath are laid across the supports. 

### **Plaster over Gypsum Lath**

  * Two-coat plaster is normally used over gypsum lath.  Veneer plaster can also be applied as a 1/16″ to 1/8″ (2 to 3) thick one-coat finish over a special gypsum board base. 
  * Supports may be spaced 16″ (405) o.c.  for ⅜″ (10) lath, and 24″ (610) o.c.  for ½″ (13) lath. 
  * The long dimension of the lath is laid across the supports; ends of lath should bear on a support or be supported by sheet metal clips. 

### **Solid Plaster Partition**

  * 2″ (51) total thickness of partition conserves floor space. 
  * Three-coat plaster is applied to both sides of metal or gypsum lath. 
  * Proprietary ceiling runners and metal base anchors are required to stabilize the partition. 

## **10.06 PLASTER DETAILS**

### **Ceiling Detail**

### **Ceiling Detail**

### **Ceiling Detail**

### **Partition End Detail**

### **Metal Door Frame**

### **Acoustic Wall Treatment**

### **Metal Door Frame**

### **Metal Door Frame**

### **Wood Door Frame**

### **Alternative Base Details**

## **10.07 PLASTER OVER MASONRY**

### **Plaster over Furring**

Plaster should be applied over lath and furring when:

  * The masonry surface is not suitable for direct application. 
  * The possibility exists that moisture or condensation might penetrate the wall. 
  * Additional air space or space for insulating material is required. 
  * A resilient wall surface is desired for acoustical treatment of the space. 

  * Wood or metal furring may be applied vertically or horizontally. 
  * Plaster requires either metal or gypsum lath over the furring; the application and support spacing are similar to the examples shown on 10.06. 
  * Wall anchors are available that adjust to various furring depths. 

### **Direct Application**

  * Two-coat plaster, 5/8″ (16) thick, is normally applied directly over masonry. 
  * Plaster may be applied directly to brick, clay tile, or concrete masonry if the surface is sufficiently rough and porous to allow for a good bond. 
  * A bonding agent is required when applying plaster directly to dense, nonporous surfaces such as concrete. 

## **10.08 PLASTER CEILINGS**

### **Control Joints**

Plaster ceilings should have control joints at least every 30′ (9145) in each direction, with a maximum area of 900 sf (84 m2) without control joints.  These joints relieve shrinkage, temperature, or structural stresses within a large plastered area. 

### **Wall and Ceiling Joints**

**No Bond Condition**

**No Bond Condition**

**Restrained Condition**

## **10.09 GYPSUM BOARD**

Gypsum board is a sheet material used for covering walls or as lath.  It consists of a gypsum core surfaced and edged to satisfy specific performance, location, application, and appearance requirements.  It has good fire resistance and dimensional stability.  In addition, its relatively large sheet size makes it an economical material to install.  Gypsum wallboard is often referred to as drywall because of its low moisture content, and little or no water is used in its application to interior walls or ceilings.  Sheetrock is a trademark for a brand of gypsum board. 

Gypsum board may have different edge conditions.  Base or intermediate boards in multilayer construction may have square or tongue-and-groove edges.  Prefinished boards may have square or beveled edges.  Most commonly, however, gypsum board has a tapered edge.  The tapered edge allows the joints to be taped and filled to produce strong, invisible seams.  Gypsum board thus can form smooth surfaces that are monolithic in appearance and that can be finished by painting or applying a paper, vinyl, or fabric wall covering. 

### **Types of Gypsum Board**

**Regular Wallboard**

  * Tapered edge
  * 4′ (1220) wide, 8′ to 16′ (2440 to 4875) long
  * ¼″ (6) board is used as the base layer in sound-control walls; ⅜″ (10) board is used in multilayer construction, and for remodeling projects; ½″ and ⅝″ (13 and 16) boards are for single-layer construction. 

**Coreboard**

  * Square or tongue-and-groove edge
  * 1″ (25) thick
  * 2′ (610) wide, 4′ to 16′ (1220 to 4875) long
  * Used to line elevator shafts, stairways, and mechanical chases, and as a base in solid gypsum partitions

**Foil-Backed Board**

  * Square or tapered edge
  * ⅜″, ½″, ⅝″ (10, 13, 16) thick
  * 4′ (1220) wide, 8′ to 16′ (2440 to 4875) long
  * Aluminum-foil backing serves as a vapor retarder and as a reflective thermal insulator when the foil faces a ¾″ (19) minimum dead air space. 

**Water-Resistant Board**

  * Tapered edge
  * ½″, ⅝″ (13, 16) thick
  * 4′ (1220) wide, 8′ to 12′ (2440 to 3660) long
  * Used as a base for ceramic or other nonabsorbent tile in high-moisture areas

**Type-X Board**

  * Tapered or rounded edge
  * ½″, ⅝″ (13, 16) thick
  * 4′ (1220) wide, 8′ to 16′ (2440 to 4875) long
  * Core has glass fibers and other additives to increase its fire-resistance; available with foil backing. 

**Prefinished Board**

  * Square edge
  * 5/16″ (8) thick
  * 4′ (1220) wide, 8′ (2440) long
  * Vinyl or printed paper surface in various colors, patterns, and textures

**Backing Board**

  * Square or tongue-and-groove edge
  * ⅜″, ½″, ⅝″ (10, 13, 16) thick
  * 4′ (1220) wide, 8′ (2440) long
  * Used as the base layer in a multilayer assembly for increased rigidity, sound insulation, and fire resistance; available with regular or Type-X cores, or with foil backing

**Sheathing Board**

  * Square or tongue-and-groove edge
  * ½″, ⅝″ (13, 16) thick
  * 2′ or 4′ (610 or 1220) wide, 8′ to 10′ (2438 to 3048) long
  * Has a fire-resistant core and is faced with a water-repellent paper for use as exterior sheathing; available with regular or Type X-cores

### **Types of Edges**

**CSI MasterFormat 09 29 00: Gypsum Board**

## **10.10 GYPSUM BOARD APPLICATION**

### **Masonry or Concrete Base**

Gypsum board may be applied to above-grade masonry or concrete walls whose surfaces are dry, smooth, even, and free of oil or other parting materials. 

### **Stud Wall Base**

Gypsum board may be fastened directly to wood or metal stud framing that is structurally sound and rigid enough to prevent buckling or cracking of the gypsum board.  The face of the frame should form a flat and even plane. 

Horizontal application is preferred for greater stiffness if it results in fewer joints.  Butt-end joints, which should be kept to a minimum, must fall over a support. 

Wood or metal furring is required when:

  * The frame or masonry base is not sufficiently flat and even. 
  * The framing supports are spaced too far apart. 
  * Additional space for thermal or acoustic insulation is desired. 
  * The use of resilient furring channels is needed to improve the acoustic performance of the assembly. 

**CSI MasterFormat 09 21 16: Gypsum Board Assemblies**

## **10.11 GYPSUM BOARD DETAILS**

### **Ceilings**

Gypsum board may be fastened directly to the undersides of joists @ 16″ (405) o.c.  The deflection of the floor or roof structure should be limited to 1/240th of its span.  For improved resistance to sound transmission, and when attaching the gypsum board to concrete or steel joists, resilient furring channels @ 16″ or 24″ (405 or 610) o.c.  are used.  For fire-resistance, Type-X board can be used; see A.12–A.13 for fire ratings of various wall and ceiling assemblies. 

  * Gypsum board may also be supported by a grid of furring channels and hung as a suspended ceiling. 

### **Walls**

### **Edges**

  * Corner bead

  * Metal edge trim
  * Various profiles are available

  * External corners and exposed edges should be protected against damage by metal corner beads and edge trims.  Metal trim accessories require finishing with a joint compound. 

## **10.12 CERAMIC TILE**

Ceramic tiles are relatively small, modular surfacing units made of clay or other ceramic material.  The tiles are fired in a kiln at very high temperatures.  The result is a durable, tough, dense material that is water-resistant, difficult to stain, and easy to clean; its colors generally do not fade. 

Ceramic tile is available glazed or unglazed.  Glazed tile has a face of ceramic material fused into the body of the tile, and may have glossy, matte, or crystalline finishes in a wide range of colors.  Unglazed tiles are hard and dense, and derive their color from the body of the clay material.  These colors tend to be more muted than those of glazed tiles. 

### **Trim Shapes**

### **Types of Ceramic Tile**

### **Glazed Wall Tile**

Glazed wall tile has a nonvitreous body and a bright, matte, or crystalline glaze, used for surfacing interior walls and light-duty floors.  Exterior tiles are weatherproof and frostproof, and can be used for both exterior and interior walls. 

  * 5/16″ (8) thick
  * 4 -¼″ x 4 -¼″ (108 x 108)
  * 4 -¼″ x 6″ (108 x 150)
  * 6″ x 6″ (150 x 150)
  * 8″ x 8″ (205 x 205)
  * 1-⅜″ (35) square
  * 4 -½″ (108) octagon
  * 5″ (125) hexagon

### **Ceramic Mosaic Tile**

Ceramic mosaic tile has a porcelain or natural clay body, glazed for surfacing walls or unglazed for use on both floors and walls.  Porcelain tiles have bright colors, while natural clay tiles have more muted colors.  To facilitate the handling and speed of installation, small tiles are usually faced with paper or backed with mesh to form 1′ x 1′ (305 x 305) or 1′ x 2′ (305 x 610) sections with the proper tile spacing. 

  * ¼″ (6) thick
  * 1″ x 1″ (25 x 25)
  * 1″ x 2″ (25 x 51)
  * 2″ x 2″ (51 x 51)
  * 1″ and 2″ (25 and 51) hexagons

### **Quarry and Paver Tiles**

Quarry tile is unglazed floor tile of natural clay or porcelain.  The tiles are impervious to dirt, moisture, and stains, and resistant to freezing and abrasion.  Pavers are similar in composition to ceramic mosaic tiles but thicker and larger.  They are weatherproof and can be used on floors subjected to heavy-duty loads. 

  * ⅜″, ½″, ¾″ (10, 13, 19) thick
  * 3″ x 3″ (75 x 75)
  * 4″ x 4″ (100 x 100)
  * 4″ x 6″ (100 x 150)
  * 6″ x 6″ (150 x 150)
  * 8″ x 8″ (205 x 205)
  * 6″ and 8″ (150 and 205) hexagons

  * Consult tile manufacturer for exact sizes, shapes, colors, and glazes. 

**CSI MasterFormat 09 30 13: Ceramic Tiling**

## **10.13 CERAMIC TILE APPLICATIONS**

### **Thinset Process**

In the thinset process, ceramic tile is bonded to a continuous, stable backing with a thin coat of dry-set mortar, latex-portland cement mortar, epoxy mortar, or an organic adhesive. 

  * Suitable floors for thinset installations include concrete slabs and double wood floors. 
  * Concrete slabs should be smooth, level, and properly reinforced and cured; a leveling topping can be used if required. 

  * Maximum deflection of the floor under full load should be limited to 1/360th of the span. 

### **Thickset Process**

In the thickset process, ceramic tile is applied over a bed of portland cement mortar.  This relatively thick bed allows for accurate slopes and true planes in the finished work.  The mortar bed is also not affected by prolonged contact with water. 

**CSI MasterFormat 09 31 00: Thinset Tiling  
CSI MasterFormat 09 32 00: Mortar-Bed Tiling**

## **10.14 CERAMIC TILE DETAILS**

### **Interior Wall Applications**

**Cement Mortar**

**Thinset Mortar**

**Organic Adhesive**

### **Interior Floor Applications**

**Cement Mortar**

**Thinset Mortar**

**Organic Adhesive**

**Ceramic Tile Shower**

**Tile Tub Enclosure**

**Tile Countertops**

## **10.15 TERRAZZO FLOORING**

Terrazzo is a mosaic floor or paving composed of marble or other stone chips, set in a cementitious or resinous matrix and ground and polished when dry.  It provides a dense, extremely durable, smooth flooring surface whose mottled coloring is controlled by the size and colors of the aggregate and the color of the binder. 

### **Terrazzo Finishes**

Metal or plastic-tipped divider strips are used:

  * To localize shrinkage cracking;
  * To serve as construction joints;
  * To separate the different colors of a floor pattern;
  * To act as decorative elements. 

  * Exterior and below-grade masonry or concrete walls require furring before the application of gypsum board to eliminate the capillary transfer of water and to minimize condensation on interior wall surfaces. 

### **Terrazzo Stair**

### **Thinset Terrazzo**

### **Monolithic Terrazzo**

### **Bonded Terrazzo**

### **Chemically Bonded Terrazzo**

### **Sand-Cushion Terrazzo**

### **Terrazzo Base**

**CSI MasterFormat 09 66 00: Terrazzo Flooring**

## **10.16 WOOD FLOORING**

Wood flooring combines durability and wear resistance with comfort and warmth.  Durable, hard, close-grained species of both hardwood and softwood are used for flooring.  Common species of hardwood flooring species include oak, maple, birch, pecan, and cherry.  Common species of softwood flooring include southern pine, Douglas fir, and hemlock.  Whenever possible, woods used for flooring should be from certified sustainable sources.  While technically not a wood, bamboo is a relatively fast-growing grass product that qualifies as a renewable resource. ( LEED® MR Credit 6: Rapidly Renewable Materials)

The various species of wood flooring are appearance-graded, but not according to the same standards.  The best grades—clear or select—typically minimize or exclude defects such as knots, streaks, checks, and torn grain.  Consult the flooring manufacturer for precise standards and specifications. 

Solid wood flooring is available in strips and planks. 

### **Strip Flooring**

Strip flooring is composed of long wood strips 3-¼″ (85) or less in face width. 

### **Plank Flooring**

Plank flooring refers to flooring boards that are wider than 3-¼″ (85).  End- and side-matched boards are blind-nailed.  The boards may also be face-nailed or screwed and then plugged.  Some new plank flooring systems can be laid with mastic or adhesive.  To minimize the effect of variations in humidity on the wide planks, 3-ply laminated planks are available. 

Wood flooring is most often finished with clear polyurethane, varnish, or a penetrating sealer.  Finishes can range from high gloss to satin.  Ideally, the finish should enhance the durability of the wood and its resistance to water, dirt, and staining, without concealing the wood's natural beauty.  Stains are used to add color to the natural color of the wood without obscuring the wood grain.  Wood flooring can also be waxed, painted, or stenciled, but painted surfaces require more maintenance. 

### **Engineered Flooring**

Engineered flooring is impregnated with acrylic or sealed with urethane or vinyl.  Laminated flooring assembles high-pressure laminates, including wood veneers, into durable, acrylic-urethane sealed panels.  Bamboo is also laminated under high pressure, milled into planks, immersed in polyurethane, and coated with acrylic polyurethane. 

**CSI MasterFormat 09 62 23: Bamboo Flooring  
CSI MasterFormat 09 64 00: Wood Flooring**

## **10.17 WOOD FLOORING INSTALLATION**

Wood strip and plank flooring requires a wood subfloor or a base of spaced wood sleepers.  Plywood or panel subfloors, integral parts of a wood joist floor system, may be laid over other floor systems as well to receive the wood flooring.  Treated wood sleepers are usually required over concrete slabs to receive a wood subfloor or the finish wood flooring.  This is especially important to protect the flooring from dampness when it is installed on concrete slabs on or below grade. 

Wood block flooring requires a clean, dry, smooth, flat surface such as a plywood subfloor or underlayment.  While block tiles can be applied to the surface of a dry concrete slab, it is best, especially in basements, to lay the flooring over a plywood subfloor and a vapor barrier set on treated wood sleepers. 

Wood flooring will shrink and swell as its moisture content changes with variations in atmospheric humidity.  It should not be installed until the building is enclosed, permanent lighting and the heating plant are installed, and all building materials are dry.  The wood flooring should be stored for several days in the space where it will be installed to allow the flooring to become acclimated to the interior conditions.  As the flooring is installed, space should be provided along the perimeter for ventilation and expansion of the flooring. 

### **Strip Flooring over Wood Subflooring**

### **Strip Flooring over Concrete Slab**

### **Floating Wood Flooring Installation**

### **Glueless Laminated Wood Flooring Installation**

## **10.18 STONE FLOORING**

Stone flooring may consist of sandstone, limestone, polished marble or granite, or split-face slate.  Consideration should be given to the color and texture of the stone finish, its abrasion- and slip-resistance, as well as the additional dead load the stone will impose on the floor structure.  Stone flooring ½″ (13) thick weighs about 7.5 psf (359 Pa). 

The tiles or slabs may be laid in regular or irregular patterns over a portland cement mortar bed in a manner similar to the installation of ceramic tile flooring.  Thin stone flooring may also be applied using the thinset process.  See 10.13. 

**CSI MasterFormat 09 63 40: Stone Flooring**

## **10.19 RESILIENT FLOORING**

Resilient flooring materials provide an economical, relatively dense, nonabsorbent flooring surface that is durable and easy to maintain.  Their degree of resilience enables them to resist permanent indentation and contributes to their quietness and comfort underfoot.  How comfortable a resilient floor covering is, however, depends not only on its resilience but also on its backing and the hardness of the supporting substrate. 

None of the resilient flooring types is superior in all respects.  Listed below are the types that perform well in specific areas. 

  * Resilience and quietness: cork tile, rubber tile, homogeneous vinyl tile
  * Resistance to indentation: homogeneous vinyl tile, vinyl sheet, cork tile w/ vinyl coating
  * Stain resistance: rubber tile, homogeneous vinyl tile, vinyl composition tile, linoleum
  * Alkali resistance: cork tile w/ vinyl coating, vinyl sheet, homogeneous vinyl tile, rubber tile
  * Grease resistance: vinyl sheet, homogeneous vinyl tile, cork tile w/ vinyl coating, linoleum
  * Durability: homogeneous vinyl tile, vinyl sheet, vinyl composition tile, rubber tile
  * Ease of maintenance: vinyl sheet, homogeneous vinyl tile, vinyl composition tile, cork tile w/ vinyl coating

### **Wood Subfloors**

### **Concrete Subfloors**

LEED EQ Credit 4.1: Low-Emitting Materials, Adhesives & Sealants

  * Various resilient flooring accessories are available for use as wall bases, stair nosings and treads, and thresholds. 

**CSI MasterFormat 09 65 00: Resilient Flooring**

## **10.20 CARPETING**

Carpeting provides floors with both visual and textural softness, resilience, and warmth in a wide range of colors and patterns.  These qualities, in turn, enable carpeting to absorb sound, reduce impact noise, and provide a comfortable and safe surface to walk on.  As a group, carpeting is also fairly easy to maintain. 

Carpeting is normally installed wall to wall, covering the entire floor of a room.  It can be laid directly over a subfloor and underlayment pad, obviating the need for a finish floor.  It can also be laid over an existing floor. 

### **Carpet Fibers**

  * Nylon: predominant face fiber; excellent strength and wearability; soil- and mildew-resistant; anti-static properties achieved through the use of conductive filaments
  * Polypropylene (Olefin): good resistance to abrasion, soil, and mildew; used extensively in outdoor carpeting
  * PET polyester: durable form of polyester made from recycled plastic containers; resists soiling, abrasion, stains, and fading. 
  * Wool: excellent resilience and warmth; good soil, flame, and solvent resistance; cleanable
  * Cotton: not as durable as other face fibers, but softness and colorability used to advantage in flat-woven rugs

  * Plastic fibers are a source of gases harmful to the respiratory system; some also yield toxic fumes when burned.  Select carpets, carpet adhesives, and carpet pads that have passed the Carpet and Rug Institute's tests for indoor air quality.  The Carpet and Rug Institute also recommends that ventilating fans be operated at full capacity and, if possible, doors and windows be opened for maximum ventilation during and for 48 to 72 hours after installation. 

  * LEED EQ Credit 4.3: Low-Emitting Materials, Carpet Systems

### **Carpet Construction**

  * Tufted carpet is made by mechanically stitching pile yarn through a primary fabric backing and bonding the yarn with latex to a secondary backing.  The majority of carpet produced today is tufted. 

  * Woven carpet is made by simultaneously interweaving the backing and pile yarns on a loom.  Woven carpet is longer-wearing and more stable than tufted carpet, but it is more expensive to produce. 

  * Knitted carpet is made by looping the backing, stitching, and pile yarns with three sets of needles. 

  * Fusion-bonded carpet is made by heat-fusing face yarns to a vinyl backing supported by other materials. 

  * Flocked carpet is made by propelling short strands of pile fiber electrostatically against an adhesive-coated backing. 

  * Needle-punched carpet is made by punching carpet fibers back and forth through a woven polypropylene sheet with barbed needles to form a felted fiber mat. 

**CSI MasterFormat 09 68 00: Carpeting**

## **10.21 CARPETING**

### **Carpet Terminology**

### **Carpet Textures**

After color, texture is the prime visual characteristic of a carpet.  The various carpet textures available are a result of the pile construction, pile height, and the manner in which the carpet is cut.  There are three major groups of carpet textures—cut pile, loop pile, and a combination of cut and loop pile. 

  * Cut pile is created by cutting each loop of pile yarn, producing a range of textures from informal shags to short, dense velvets. 

  * Loop pile is created by weaving, tufting, or knitting the pile yarn into loops.  Loop pile is tougher and more easily maintained than cut pile but is less versatile in color and pattern. 

### **ADA Accessibility Guidelines**

  * Securely attach carpet to a firm underlayment. 

  * Fasten and trim all exposed edges to the floor surface. 
  * Bevel edge trim to a slope of 1:20 if more than ¼″ (6) high. 

## **10.22 ACOUSTICAL CEILING TILES**

Acoustical ceiling tiles are made in various sizes and textures from a soft, sound-absorbing material, such as cork, mineral fiber, or glass fiber.  These modular units have perforated, patterned, textured, or fissured faces that allow sound to penetrate into the fiber voids.  Because of their light weight and low density, the tiles can be easily damaged.  To improve their resistance to humidity, impact, and abrasion, the tiles may be factory-painted or have a ceramic, plastic, steel, or aluminum facing. 

  * Acoustical ceiling tiles are manufactured in 12″ x 12″ (305 x 305), 24″ x 24″ (610 x 610), and 24″ x 48″ (610 x 1220) modules.  Tiles based on 20″, 30″, 48″, and 60″ (510, 760, 1220, and 1525) dimensions are also available. 

  * Typical tile thicknesses: ½″, ⅝″, ¾″ (13, 16, 19)
  * Tiles may have square, beveled, rabbeted, or tongue-and-groove edges. 

  * Metal pan tiles consist of a steel or aluminum pan having a perforated face and containing a separate layer of sound-absorbing material. 

Consult the ceiling tile manufacturer for:

  * Sizes, patterns, and finishes
  * Noise-reduction coefficient (NRC)
  * Fire rating
  * Light-reflectance value
  * Suspension-system details

### **Direct Application of Acoustical Ceilings**

**Set with Adhesive**

**Fastened to Furring**

**Sprayed On**

**CSI MasterFormat 09 51 00: Acoustical Ceilings**

## **10.23 SUSPENDED ACOUSTICAL CEILINGS**

Acoustical ceiling tiles can be suspended from an overhead floor or roof structure to provide a concealed space for mechanical ductwork, electrical conduit, and plumbing lines.  Light fixtures, sprinkler heads, fire detection devices, and sound systems can be recessed into the ceiling plane.  The ceiling membrane can be fire-rated and provide fire protection for the supporting floor and roof structure.  Thus, the ceiling system is able to integrate the functions of lighting, air distribution, acoustical control, and fire protection. 

Although the suspension systems of each manufacturer may vary in their details, they all consist of a grid of main channels or runners, cross tees, and splines.  This grid, suspended from the overhead floor or roof structure, may be exposed, recessed, or fully concealed.  In most suspension systems, the acoustical tiles are removable for replacement or for access into the ceiling space. 

Ceiling canopies and clouds are made of fabric, acoustical tile, metal, translucent plastic, or other materials.  Suspended from pendants or wires, they allow ceilings to be dropped over small areas, even below other ceiling finish materials, and usually allow access to equipment above. 

Integrated ceiling systems incorporate acoustical, lighting, and air-handling components into a unified whole.  The suspension systems, which typically form a 60″ x 60″ (1525 x 1525) grid, may support either flat or coffered acoustical panels.  Air-handling components may be integral parts of modular luminaires and disperse conditioned air along the edges of the fixtures, or be integrated into the suspension system and diffuse conditioned air through long, narrow slots between the ceiling panels. 

  * Exposed grid suspension systems support the acoustical tiles with inverted tees. 

  * Recessed grid suspension systems support acoustical tiles within rabbeted joints. 

  * Concealed grid suspension systems are hidden within kerfs cut into the edges of the acoustical tiles. 

Linear metal ceilings consist of narrow anodized aluminum, painted steel, or stainless steel strips.  The slots between the spaced strips may be open or closed.  Open slots permit sound to be absorbed by a backing of batt insulation in the ceiling space.  Linear metal ceiling systems usually incorporate modular lighting and air-handling components. 

**CSI MasterFormat 09 53 00: Acoustical Ceiling Suspension Assemblies  
CSI MasterFormat 09 54 00: Specialty Ceilings**

## **10.24 WOOD JOINTS**

The strength and rigidity of ordinary wood framing are more important than its appearance because it is normally covered with a finish surface.  In finish trim, cabinetry, and furniture work, however, the appearance of a wood joint becomes just as important as its strength.  Small-scale work requires more sophisticated and refined joints that present a clean appearance. 

Wood joints can express the manner in which the members are connected, or they can be relatively inconspicuous.  In either case, they must remain tight.  If they open due to the shrinkage or structural movement of the wood, they become both weaker and more noticeable. 

In designing and constructing a wood joint, it is important to understand the basic nature of the compressive, tensile, shear forces acting on the joint, and to comprehend their relationship to the direction of the wood grain.  See 12.11. 

### **End Joints**

### **Edge Joints**

### **Angle Joints**

### **Miter Joints**

**CSI MasterFormat 06 20 00: Finish Carpentry**

## **10.25 WOOD JOINTS**

### **Lap Joints**

  * Mitered halving

  * Cross lap

  * End lap

### **Dovetail Joints**

  * Halving refers to cutting away half of each member at the place of joining so that a flush surface results. 

  * Dovetail halving

  * Secret dovetail or blind miter

  * Lap or half-blind dovetail

### **Mortise-and-Tenon Joints**

## **10.26 WOOD MOLDINGS & TRIM**

## **10.27 WOOD MOLDINGS & TRIM**

For use as trim, a variety of stock wood moldings are available at millwork shops.  They vary in section, length, and species of wood.  They can be used singly or be combined to form more complex sections.  In addition to these stock sections, wood moldings can be milled to custom specifications. 

The type of wood used for trim depends on the type of finish to be applied to the woodwork.  For painted finishes, the wood should be close-grained, smooth, and free of pitch streaks or other imperfections.  If the woodwork is to receive a transparent or natural finish, the wood should have a uniform color, an attractive figure, and a degree of hardness. 

Interior trim is normally applied after the finish walls, ceiling, and flooring are in place.  Although decorative in nature, interior trim also serves to conceal, finish, and perfect the joints between interior materials. 

### **Casings**

  * Head and jamb casings for windows and doorways are generally treated in a similar manner. 

## **10.28 WOOD PANELING**

Interior wood paneling may consist of veneer-faced panels applied directly to wood or metal framing or furring.  Furring is required over masonry or concrete walls.  Furring may also be used over frame walls when improved thermal insulation properties, greater acoustical isolation, or additional wall depths are desired.  The panels are normally fastened with nails or screws although adhesives can be used for greater rigidity.  The final appearance of the paneled wall will depend on the treatment of the joints and the grain or figure of the wood panels. 

Solid wood planks may also be used for interior paneling.  The planks may have square cut, tongue-and-groove, or shiplap edges.  The resulting wall pattern and texture will depend on the plank width, orientation, spacing, and joint details. 

**CSI MasterFormat 06 42 00: Wood Paneling**

## **10.29 PLYWOOD VENEER**

Decorative plywood panels are available with hardwood or softwood face veneers for use as wall paneling, cabinetry, and furniture work.  The panels are typically 4′ x 8′ (1220 x 2440) and available in ¼″, ⅜″, ½″, and ¾″ (6, 10, 13, and 19) thicknesses. 

### **Matching Patterns**

The appearance of naturally finished plywood paneling depends on the species of wood used for the face veneer and the way in which the sheets of veneer are arranged so as to emphasize the color and figure of the wood. 

### **Softwood Veneer Grades**

N – select, smooth surface for natural finishes  
A – smooth face suitable for painting  
B – solid surface utility panel

### **Hardwood Veneer Grades**

  * Premium grade permits only a few small burls, knots, and inconspicuous patches. 
  * Good grade is similar to premium grade except that matching of veneer faces is not required and no sharp contrasts in color are allowed. 
  * Sound grade is a smooth veneer free of open defects but containing streaks, discoloration, patches, and small, sound, and tight knots. 
  * Utility grade permits discoloration, streaks, patches, tight knots, small knotholes, and splits. 
  * Backing grade permits larger defects not affecting the strength or durability of the panel. 

### **Grain Figures**

Figure refers to the natural pattern on a sawn wood surface produced by the intersection of annual rings, knots, burls, rays, and other growth characteristics.  Different figures may be produced by varying the way in which a wood veneer is cut from a log. 

  * Rotary cutting against the edge of a knife in a lathe produces a continuous veneer with a variegated ripple figure. 

  * Flat or plain slicing of a half-log parallel to a line through its center produces a variegated wavy figure. 

  * Quarter slicing of a log perpendicular to the annual rings produces a series of straight or varied stripes in the veneer. 

  * Half-round slicing of a flitch mounted off-center in the lathe, slightly across the annual rings, produces characteristics of both rotary cutting and flat slicing. 

  * Rift cutting is the slicing of oak and similar species perpendicular to the conspicuous, radiating rays so as to minimize their appearance. 

LEED EQ Credit 4.4: Low-Emitting Materials, Composite Wood & Agrifiber Products

**CSI MasterFormat 06 42 16: Wood-Veneer Paneling**

## **10.30 PLASTIC LAMINATE**

Plastic laminate is a hard surfacing material consisting of superposed layers of kraft paper, foil, printed paper, wood veneer, or fabric impregnated with melamine and phenolic resins, fused together under heat and pressure.  Plastic laminates provide a durable, heat- and water-resistant surface covering for countertops, furniture, doors, and wall panels.  They may be applied to smooth plywood, hardboard, particleboard, and other common core materials.  They may be bonded with contact adhesive in the field or with thermosetting adhesive, under pressure, in the shop. 

  * High-pressure laminate is molded and cured in the range of pressures from 1200 to 2000 psi (84 to 140 kg/m2), and used for surfacing countertops and tabletops. 
  * Low-pressure laminate is molded and cured with a maximum pressure of 400 psi (28 kg/m2), and used in vertical and low-wear applications. 
  * Formica is a trademark for a brand of plastic laminate. 
  * Plastic laminate surfaces with tight rolls and bends should be postformed during manufacture and bonded with thermosetting adhesive.  Postformed plastic laminate 1/20″ (1.2 mm) thick may be bent to a radius as small as ¾″ (19).  Plastic laminate edge banding may be bent to a radius of 3″ (75) or smaller if heated. 

### **Plastic Laminate Countertops**

### **Edge Treatments for Plastic-Laminate-Faced Panels**

**CSI MasterFormat 06 41 16: Plastic-Laminate-Clad Architectural Cabinets  
CSI MasterFormat 09 62 19: Laminate Flooring  
CSI MasterFormat 12 36 23.13: Plastic-Laminate-Clad Countertops**

EQ Credit 4.1: Low-Emitting Materials, Adhesives & Sealants

# **Chapter 11**  
 **MECHANICAL & ELECTRICAL SYSTEMS**

11.02 Mechanical & Electrical Systems

11.03 Thermal Comfort

11.04 Comfort Zone

11.05 Psychrometric Charts

11.06 Heating & Cooling Systems

11.07 Alternative Energy Sources

11.09 Heating & Cooling Loads

11.10 Forced-Air Heating

11.11 Hot-Water Heating

11.12 Electric Heating

11.13 Radiant Heating

11.15 Active Solar Energy Systems

11.16 Cooling Systems

11.17 HVAC Systems

11.21 Air Distribution Outlets

11.22 Water Supply

11.23 Water Supply Systems

11.25 Fire Protection Systems

11.26 Plumbing Fixtures

11.27 Sanitary Drainage Systems

11.29 Sewage Disposal Systems

11.30 Electric Power

11.31 Electrical Service

11.33 Electrical Circuits

11.34 Electrical Wiring

11.35 Access Flooring Systems

11.36 Electrical Outlets

11.37 Light

11.38 Light & Vision

11.39 Light Sources

11.43 Luminaires

11.44 Lighting

## **11.02 MECHANICAL & ELECTRICAL SYSTEMS**

This chapter discusses the mechanical and electrical systems that are required to maintain the necessary conditions of environmental comfort, health, and safety for the occupants of a building.  The intent is not to provide a complete design manual but to outline those factors that should be considered for the successful operation of these systems and their integration with other building systems. 

Heating, ventilating, and air-conditioning systems condition the interior spaces of a building for the environmental comfort of the occupants.  A potable water supply is essential for human consumption and sanitation.  The efficient disposal of fluid waste and organic matter is necessary in order to maintain sanitary conditions within a building and in the surrounding area.  Electrical systems furnish light and heat for a building's occupants, and power to run its machines. 

These systems require a significant amount of space.  Because much of the hardware for these systems is normally hidden from view—within concealed construction spaces or special rooms—the layout of these systems should be carefully integrated with each other as well as with the structural and enclosure systems of the building. 

## **11.03 THERMAL COMFORT**

At rest, the human body produces about 400 Btu/h (117 W) of energy.  Moderate activities like walking can raise this amount to 750 Btu/h (220 W), while strenuous activities can cause the body to generate up to 1200 Btu/h (351 W).  Thermal comfort is achieved when the human body is able to dissipate the heat and moisture it produces by metabolic action in order to maintain a stable, normal body temperature.  In other words, thermal equilibrium must exist between the body and its environment. 

The human body loses or transfers heat to the surrounding air and surfaces in the following ways. 

### **Conduction**

  * Conduction is the transfer of heat from the warmer to the cooler particles of a medium or of two bodies in direct contact, occurring without perceptible displacement of the particles themselves. 
  * Conduction accounts for a very small portion of the total heat loss from the body. 

### **Convection**

  * Convection is the transfer of heat by the circulatory motion of the heated parts of a liquid or gas owing to a variation in density and the action of gravity.  In other words, the body gives off heat to the surrounding cooler air. 
  * A large differential between air and skin temperature and increased air motion induce more heat transmission by convection. 

### **Radiation**

  * Radiation is the process by which heat energy in the form of electromagnetic waves is emitted by a warm body, transmitted through an intervening space, and absorbed by a cooler body.  No air motion is required for the transfer of heat. 
  * Light colors reflect while dark colors absorb heat; poor reflectors make good radiators. 
  * Radiant heat cannot travel around corners and is not affected by air motion. 

### **Evaporation**

  * Heat is required for the evaporative process of converting body moisture into a vapor. 
  * Heat loss by evaporation increases with air motion. 
  * Evaporative cooling is especially beneficial when high air temperatures, humidity, and activity levels exist. 

## **11.04 COMFORT ZONE**

Factors affecting human comfort include air temperature, relative humidity, mean radiant temperature, air motion, air purity, sound, vibration, and light.  Of these, the first four are of primary importance in determining thermal comfort.  Certain ranges of air temperature, relative humidity, mean radiant temperature, and air motion have been judged to be comfortable by a majority of Americans and Canadians tested.  These comfort zones are described by the following graphs of the interaction between the four primary thermal comfort factors.  Note that a specific level of comfort for any individual is a subjective judgment of these thermal comfort factors and will vary with prevailing and seasonal variations in climate as well as the age, health, clothing, and activity of the individual. 

LEED® EQ Credit 7: Thermal Comfort

### **Air Temperature and Mean Radiant Temperature**

  * Mean radiant temperature (MRT) is important to thermal comfort because the human body receives radiant heat from or loses heat by radiation to the surrounding surfaces if their MRT is significantly higher or lower than the air temperature.  See diagram on following page. 
  * The higher the MRT of the surrounding surfaces, the cooler the air temperature should be. 
  * MRT has about 40% more effect on comfort than air temperature. 
  * In cold weather, the MRT of the interior surfaces of exterior walls should not be more than 5°F (2.8°C) below the indoor air temperature. 

### **Air Temperature and Relative Humidity**

  * Relative humidity (RH) is the ratio of the amount of water vapor actually present in the air to the maximum amount that the air could hold at the same temperature, expressed as a percentage. 
  * The higher the relative humidity of a space, the lower the air temperature should be. 
  * Relative humidity is more critical at high temperatures than within the normal temperature range. 
  * Low humidity (<20%) can have undesirable effects such as the buildup of static electricity and the drying out of wood; high humidity can cause condensation problems. 

### **Air Temperature and Air Motion**

  * Air motion (V) increases heat loss by convection and evaporation. 
  * The cooler the moving air stream is, relative to the room air temperature, the less velocity it should have. 
  * Air velocity should range between 10 and 50 feet per minute (fpm) [3 and 15 meters per minute (mpm)]; higher velocities can cause drafty conditions. 
  * Air motion is especially helpful for cooling evaporation in hot, humid weather. 

## **11.05 PSYCHROMETRIC CHARTS**

A psychrometer is an instrument for measuring atmospheric humidity, consisting of two thermometers, the bulb of one being dry and the bulb of the other being kept moist and ventilated so that the cooling that results from evaporation makes it register a lower temperature than the dry one, with the difference between the readings being a measure of atmospheric humidity.  Psychrometric charts relate the wet-bulb and dry-bulb readings from a psychrometer to relative humidity, absolute humidity, and dew point.  Mechanical engineers use psychrometric charts to determine the amount of heat that must be added or removed by an HVAC system to achieve an acceptable level of thermal comfort in a space. 

  * Adiabatic heating is a rise in temperature occurring without the addition or removal of heat, as when excess water vapor in the air condenses and the latent heat of vaporization of the water vapor is converted to sensible heat in the air. 

  * Mean radiant temperature (MRT) is the sum of the temperatures of the surrounding walls, floor, and ceiling of a room, weighted according to the solid angle subtended by each at the point of measurement. 

  * Evaporative cooling is a drop in temperature occurring without the addition or removal of heat, as when moisture evaporates and the sensible heat of the liquid is converted to latent heat in the vapor. 

## **11.06 HEATING & COOLING SYSTEMS**

The siting, orientation, and construction assemblies of a building should minimize heat loss to the outside in cold weather and minimize heat gain in hot weather.  Any excessive heat loss or heat gain must be balanced by passive energy systems or by mechanical heating and cooling systems in order to maintain conditions of thermal comfort for the occupants of a building.  While heating and cooling to control the air temperature of a space is perhaps the most basic and necessary function of a mechanical system, attention should be paid to the other three factors that affect human comfort—relative humidity, mean radiant temperature, and air motion. 

LEED EQ Credit 7: Thermal Comfort

The traditional fossil fuels—gas, oil, and coal—continue to be the most commonly used to produce the energy for heating and cooling buildings.  Natural gas burns cleanly and does not require storage or delivery except through a pipeline.  Propane gas is also a clean-burning fuel that is slightly more expensive than natural gas.  Oil is an efficient fuel choice, but it requires delivery by trucks to storage tanks located in or near the point of utilization.  Coal is rarely used for heating in new residential construction; its use fluctuates in commercial and industrial construction. 

Electricity is a clean energy source requiring no combustion or fuel storage at the site.  It is also a compact system, being distributed through small wires and using relatively small and quiet equipment.  However, the cost to electrically heat or cool a building can be prohibitive and most electric power must be generated by using other sources of energy—nuclear fission or the burning of fossil fuels—to drive turbines.  Nuclear energy, despite continuing concerns with the safety of its installations and the disposal of nuclear waste material, may still become an important source of power.  A small percentage of turbines are driven by flowing water (hydropower), wind, and the gases produced by burning natural gas, oil, and coal. 

Of increasing concern are the uncertain cost and availability of conventional energy sources, the impact of energy extraction and production on environmental resources, and the burning of greenhouse-gas-emitting fossil fuels (see 1.06).  Because more than 40% of all energy and more than 65% of all electricity in the United States are consumed in buildings, the design professions, construction industry, and governmental agencies are exploring strategies for reducing the energy consumption of buildings and evaluating alternative, renewable sources of energy: solar, wind, biomass, hydrogen, hydropower, ocean, and geothermal. 

## **11.07 ALTERNATIVE ENERGY SOURCES**

### **Solar Energy**

Solar energy can be used directly for passive heating, daylighting, hot water heating, and generating electricity with photovoltaic (solar cell) systems.  The conversion efficiency is low with present technology but some systems may be able to produce enough electricity to operate off-grid or to sell the extra electricity to the public utility.  Businesses and industry can employ larger-scale applications of solar technology for preheating ventilation air, solar process heating, and solar cooling.  Utilities and power plants are also taking advantage of the sun's energy in concentrating solar power systems to produce electricity on a larger scale.  These large-scale systems require sizable installations as well as a means of storing the electricity when the sun is not available to produce it. 

### **Wind Power**

Wind power is the process by which a turbine converts the kinetic energy of wind flow into mechanical power that a generator can use to produce electricity.  The technology consists of blades, sails, or hollow drums that catch the flow of winds and rotate, causing a shaft connected to a generator to turn.  Small wind turbines can be used to pump water and power homes and telecommunication dishes; some can be connected to a utility power grid or be combined with a photovoltaic (solar cell) system.  For utility-scale sources of wind energy, a large number of wind turbines are usually built close together to form a wind plant.  Like solar power, wind power is dependent upon location and weather and can be intermittent; the electricity generated when the wind is blowing cannot be stored without batteries.  The best sites for wind farms are often remote and distant from where the electricity is needed.  Additional concerns include the aesthetics of wind turbines, noise, and the potential for birdkill. 

### **Biomass Energy**

Biomass, the organic matter that makes up plants, can be used to produce electricity, transportation fuels, and chemicals that would otherwise be made from fossil fuels.  Properly harvested wood is one example of a natural and sustainable biomass, but its burning can create air pollution and harm indoor air quality.  Wood-burning appliances should meet Environmental Protection Agency (EPA) regulations for emissions.  Wood pellets made from wood by-products burn cleanly and should be considered as an alternative.  Other viable sources of biomass include food crops, such as corn for ethanol and soybeans for biodiesel, grassy and woody plants, residues from forestry or agriculture, and the organic component of municipal and industrial wastes. 

Some consider biomass to be a carbon-neutral fuel because its burning does not release more carbon dioxide than that captured in its own growth and released by its natural biodegradation.  The conversion process of biomass into fuel, however, can be energy negative if more energy is required for the conversion process than is obtained from the product itself.  Using grain such as corn also precludes it from being used as food for humans or livestock. 

### **Hydrogen**

Hydrogen is the most abundant element on earth and can be found in many organic compounds as well as water.  While it does not occur naturally as a gas, once separated from another element, hydrogen can be burned as a fuel or used by fuel cells to electrochemically combine with oxygen to produce electricity and heat, emitting only water vapor in the process.  Because hydrogen has very high energy for its weight, but very low energy for its volume, new technology is needed to more efficiently store and transport it. 

LEED EA Credit 2: On-Site Renewable Energy  
LEED EA Credit 6: Green Power

## **11.08 ALTERNATIVE ENERGY SOURCES**

### **Hydropower**

Hydroelectric power, or hydropower, is created and controlled by the damming of rivers.  As the water stored behind a dam is released at high pressure, its kinetic energy is transformed into mechanical energy and used by turbine blades to generate electricity.  Because the water cycle is an endless, constantly recharging system, hydropower is considered a clean, renewable energy source, but hydropower plants can be impacted by drought.  Benefits of hydropower include flood control and the recreational opportunities afforded by the reservoirs created by dams.  Disadvantages include enormous installation costs, loss of farmland, disruption of fish migration, and uncertain effects on riparian habitats and historical sites. 

### **Ocean Energy**

Covering more than 70% of the earth's surface, the ocean can produce thermal energy from the sun's heat and mechanical energy from its tides and waves.  Ocean Thermal Energy Conversion (OTEC) is a process for generating electricity from the heat energy stored in the earth's oceans.  The process works best in tropical coastal areas, where the surface of the ocean is warm and the depths are cold enough to create a modest temperature differential.  OTEC utilizes this temperature differential to run a heat engine—pumping warm surface-seawater through a heat exchanger where a low-boiling-point fluid, such as ammonia, is vaporized, with the vapor expanding to rotate a turbine connected to a generator.  Cold deep-seawater—pumped through a second heat exchanger—condenses the vapor back into a liquid, which is then recycled through the system.  Because its conversion efficiency is very low, an OTEC plant would have to be vast and move an enormous amount of water while anchored in the deep open ocean subject to storms and corrosion. 

Similar to more conventional hydroelectric dams, the tidal process uses the natural motion of the tides to fill reservoirs, which are then discharged through electricity-producing turbines.  Because seawater has a much higher density than air, ocean currents carry significantly more energy than wind currents.  Utilizing tidal power requires a high tide and special coastline conditions present in both the northeastern and northwestern coasts of the United States.  Damming estuaries would have considerable environmental impact, affecting both sea life migration and fisheries. 

Wave energy can be converted into electricity through both offshore and onshore systems.  Offshore systems are situated in deep water and use either the bobbing motion of the waves to power a pump or the funneling of waves through internal turbines on floating platforms to create electricity.  Onshore wave power systems are built along shorelines to extract the energy in breaking waves by using the alternating compression and depressurization of an enclosed air column to drive turbines.  The potential energy of waves can be effectively harvested in only certain areas of the world, such as the northeastern and northwestern coasts of the United States.  Careful site selection is the key to keeping the environmental impacts of wave power systems to a minimum, preserving scenic shorefronts, and avoiding altering flow patterns of sediment on the ocean floor. 

### **Geothermal Energy**

Geothermal energy—the earth's internal heat—can yield warmth and power for a variety of uses without burning fuels, damming rivers, or harvesting forests.  The shallow ground near the earth's surface maintains a relatively constant temperature of 50°–60°F (10°–16°C), heat that can be used to provide direct heating and cooling in homes and other buildings.  Steam, heat or hot water from deeper geothermal reservoirs can provide the force that spins turbine generators to produce electricity.  The used geothermal water is then returned down an injection well into the reservoir to be reheated, to maintain pressure, and to sustain the reservoir. 

## **11.09 HEATING & COOLING LOADS**

Calculating heat loss in cold weather and heat gain in hot weather is necessary to size the heating and cooling equipment required for a building.  It takes into account the differential between desired indoor air temperature and outdoor design temperature, the daily temperature range, the solar orientation and thermal resistance of wall, window, and roof assemblies, and the use and occupancy of inhabited spaces.  The more heat loss and heat gain can be reduced by the siting, layout, and orientation of a building, the less energy will be consumed by smaller heating and cooling equipment.  Other energy-conscious design strategies include using thermal insulation and thermal mass to effectively control the transmission of heat through building assemblies; making wise choices in selecting energy-efficient HVAC systems, water heaters, appliances, and lighting systems; and employing "smart" systems to control thermal conditions and lighting. 

### **Heating Load**

  * Heating load is the hourly rate of net heat loss in an enclosed space, expressed in Btu per hour and used as the basis for selecting a heating unit or system. 
  * British thermal unit (Btu) is the quantity of heat required to raise the temperature of 1 lb. ( 0.4 kg) of water 1°F. 
  * Degree-day is a unit that represents 1 degree of departure in the mean daily outdoor temperature from a given standard temperature.  It is used to compute heating and cooling loads, size HVAC systems, and calculate yearly fuel consumption. 
  * Heating degree-day is one degree-day below the standard temperature of 65°F (18°C), used in estimating fuel or power consumption by a heating system. 

### **Cooling Load**

  * Cooling load is the hourly rate of heat gain in an enclosed space, expressed in Btu per hour and used as the basis for selecting an air-conditioning unit or cooling system. 
  * Cooling degree-day is one degree-day above the standard temperature of 75°F (24°C), used in estimating energy requirements for air-conditioning and refrigeration. 
  * Ton of refrigeration is the cooling effect obtained when 1 ton of ice at 32°F (0°C) melts to water at the same temperature in 24 hours, equivalent to 12,000 Btu/hr (3.5 kW). 
  * Energy efficiency rating is an index of the efficiency of a refrigerating unit, expressing the Btu removed per watt of electrical energy input. 

  * For more detailed information on the calculation of heating and cooling loads, refer to the handbook published by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). 

### **Heat Loss**

The primary sources of heat loss in cold weather are:

  * Convection, radiation, and conduction of heat through exterior wall, window, and roof assemblies to the outside, and through floors over unheated spaces
  * Infiltration of air through cracks in exterior construction, especially around windows and doorways

LEED EA Credit 1: Optimize Energy Performance

### **Heat Gain**

Sources of heat gain in warm or hot weather include:

  * Convection, radiation, and conduction through exterior wall, window, and roof assemblies when outdoor temperatures are high; varies with the time of day, the solar orientation of the assemblies, and the effect of thermal lag
  * Solar radiation on glazing; varies with solar orientation and the effectiveness of any shading devices used
  * Building occupants and their activities
  * Lighting and other heat-producing equipment
  * Ventilation of spaces that may be required to remove odors and pollutants
  * Latent heat, requiring energy to condense the moisture in warm air so that the relative humidity in a space will not be excessive

## **11.10 FORCED-AIR HEATING**

Forced-air heating is a system for heating by means of air heated in a gas, oil, or electric furnace and distributed by a fan through ductwork to registers or diffusers in inhabited spaces.  It is the most versatile and widely used system for heating houses and small buildings. 

**CSI MasterFormat™ 23 30 00: HVAC Air Distribution  
CSI MasterFormat 23 50 00: Central Heating Equipment  
CSI MasterFormat 23 55 00: Fuel-Fired Heaters**

## **11.11 HOT-WATER HEATING**

Hot-water or hydronic heating is a system for heating a building by means of water heated in a boiler and circulated by a pump through pipes to radiators or convectors.  Steam heating is similar in principle, using steam generated in a boiler and circulating it through piping to radiators.  In large cities and building complexes, hot water or steam generated at a central boiler plant may be available via underground pipelines.  This availability would eliminate the need for an on-site boiler. 

  * Boiler is a closed vessel or arrangement of vessels and tubes in which water is heated or steam is generated.  The heat may be supplied by the combustion of gas or oil, or by electric-resistance coils.  Safety relief valves on boilers open when actuated by a vapor pressure above a predetermined level, allowing the vapor to escape until its pressure is reduced to a safe or acceptable level. 

## **11.12 ELECTRIC HEATING**

Electric heating is more accurately described as electric-resistance heating.  Resistance is the property of a conductor by virtue of which the passage of current is opposed, causing electric energy to be converted into heat.  Electric-resistance heating elements may be exposed to the air stream in a furnace or ductwork in a forced-air heating system or provide the heat for a boiler in a hydronic heating system.  More direct means of heating with electric energy involves housing the resistance wires or coils in space-heating units.  While compact and versatile, these electric-resistance heaters have no provision for controlling humidity and air quality. 

### **Comparative Heat Values of Energy Sources**

**CSI MasterFormat 23 83 00: Radiant Heating Units  
CSI MasterFormat 23 83 33: Electric Radiant Heaters**

## **11.13 RADIANT HEATING**

Radiant heating systems use heated ceilings, floors, and sometimes walls, as radiating surfaces.  The heat source may be pipes or tubing carrying hot water or electric-resistance heating cables embedded within the ceiling, floor, or wall construction.  The radiant heat is absorbed by surfaces and objects in the room, reradiates from the warmed surfaces, and raises the mean radiant temperature (MRT) as well as the ambient temperature in the space. 

Radiant heat:

  * Travels in a direct path;
  * Cannot travel around corners and may therefore be obstructed by physical elements within the space such as furniture;
  * Cannot counteract cold downdrafts along exterior glass areas;
  * Is not affected by air motion. 

Floor installations are effective in warming concrete slabs.  In general, however, ceiling installations are preferred because ceiling constructions have less thermal capacity and can respond faster.  Ceiling panels can also be heated to a higher surface temperature than floor slabs.  In both electric and hot-water radiant systems, the installations are completely concealed except for thermostats or balancing valves. 

Because radiant panel heating systems cannot respond quickly to changing temperature demands, they may be supplemented with perimeter convector units.  For complete air-conditioning, separate ventilating, humidity control, and cooling systems are required. 

**CSI MasterFormat 23 83 13: Radiant-Heating Electric Cables  
CSI MasterFormat 23 83 23: Radiant-Heating Electric Panels**

## **11.14 RADIANT HEATING**

Liquid radiant heating systems circulate warm water through metal or plastic pipes either encased in a concrete slab that serves as a thermal mass or secured to the underside of subflooring with conductive heat plates.  The supply water may be heated in a boiler, heat pump, solar collector, or geothermal system.  In response to the thermostat setting, a control valve adjusts the supply water temperature by mixing it with the circulating water from the pipe loops. 

**CSI MasterFormat 23 83 16: Radiant-Heating Hydronic Piping**

## **11.15 ACTIVE SOLAR ENERGY SYSTEMS**

Active solar energy systems absorb, transfer, and store energy from solar radiation for building heating and cooling.  They normally consist of the following components:

  * Solar collector panels
  * Circulation and distribution system for the heat transfer medium
  * Heat exchanger and storage facility

  * The heat distributing components of the solar energy system are similar to those of conventional systems. 
  * Heat may be delivered by an all-air or an air-water system. 
  * For cooling, a heat pump or absorption cooling unit is required. 
  * A backup heating system is recommended. 

  * For an active solar energy system to be efficient, the building itself must be thermally efficient and well insulated.  Its siting, orientation, and window openings should take advantage of the seasonal solar radiation. 

  * See 1.16–1.17 for passive solar design. 
  * See 11.32 for photovoltaic technology. 

**CSI MasterFormat 23 56 00: Solar Energy Heating Equipment**

## **11.16 COOLING SYSTEMS**

### **Compressive Refrigeration**

Compressive refrigeration is a process in which cooling is effected by the vaporization and expansion of a liquid refrigerant. 

### **Heat Pumps**

Heat pumps are electrically powered heating and cooling units.  For cooling, the normal compressive refrigeration cycle is used to absorb and transfer excess heat to the outdoors.  For heating, heat energy is drawn from the outdoor air by reversing the cooling cycle and switching the heat exchange functions of the condenser and evaporator. 

Heat pumps are most efficient in moderate climates where heating and cooling loads are almost equal.  In freezing temperatures, a heat pump requires an electric resistance heater to keep the outdoor coils from freezing. 

**CSI MasterFormat 23 60 00: Central Cooling Equipment**

## **11.17 HVAC SYSTEMS**

Heating, ventilating, and air-conditioning (HVAC) systems simultaneously control the temperature, humidity, purity, distribution, and motion of the air in the interior spaces of a building. 

**CSI MasterFormat 23 70 00: Central HVAC Equipment**

## **11.18 HVAC SYSTEMS**

### **All-Air Systems**

  * In a single-zone system, a master thermostat regulates the temperature for the entire building. 
  * In a multizone system, separate ducts from a central air-handling unit serve each of a number zones. 

### **All-Water Systems**

  * Pipes, which require less installation space than air ducts, deliver hot or chilled water to fan-coil units in the served spaces. 

## **11.19 HVAC SYSTEMS**

### **Air-Water Systems**

  * The primary air draws in room air through a filter and the mixture passes over coils that are heated or chilled by secondary water piped from a boiler or chilled-water plant. 
  * Local thermostats control water flow over the coils to regulate air temperature. 

### **Packaged Systems**

  * Packaged systems are self-contained, weatherproof units incorporating a fan, filters, compressor, condenser, and evaporator coils for cooling.  For heating, the unit may operate as a heat pump or contain auxiliary heating elements.  Packaged systems are powered by electricity or by a combination of electricity and gas. 

  * Rooftop packaged units may be placed at intervals to serve long buildings. 
  * Packaged systems with vertical shafts that connect to horizontal branch ducts can serve buildings up to four or five stories in height. 

## **11.20 HVAC SYSTEMS**

Factors to consider in the selection, design, and installation of a heating, ventilating, and air-conditioning system include:

  * Performance, efficiency, and both the initial and life costs of the system
  * Fuel, power, air, and water required and the means for their delivery and storage; some equipment may require direct access to the outdoors. 
  * Flexibility of the system to service different zones of a building, which may have different demands because of use or site orientation.  Decentralized or local systems are economical to install, require short distribution runs, and allow each space or zone to have individual temperature control, while central systems are generally more energy-efficient, easier to service, and offer better control of air quality. 
  * Type and layout of the distribution system used for the heating and cooling media.  To minimize friction loss, ductwork and piping should have short, direct runs with a minimum of turns and offsets. 
  * Space requirements for the mechanical equipment and the distribution system.  The heating, ventilating, and air-conditioning equipment of a building can often occupy 10% to 15% of the area of a building; some pieces of equipment also require space or a domain for access, service, and maintenance.  Air duct systems require more space than either pipes carrying hot or chilled water or wiring for electric resistance heating.  Ductwork should therefore be carefully laid out to be integrated with the structure and spaces of a building, as well as with its plumbing and electrical systems. 
  * Access required for service and maintenance
  * Construction requirements for the enclosure of the mechanical plant, fire resistance, and noise and vibration control
  * Structural requirements imposed by the weight of the equipment
  * Degree of visibility, whether concealed within the construction or exposed to view.  If ductwork is to be left exposed, the layout should have a visually coherent order and be coordinated with the physical elements of the space (e.g., structural elements, lighting fixtures, surface patterns). 

  * A single core is often used in high-rise office buildings to leave a maximum amount of unobstructed rentable area. 
  * Central locations are ideal for short runs and efficient distribution patterns. 

  * Placing the core along an edge leaves an unobstructed floor space but occupies a portion of the daylit perimeter. 

  * Detached cores leave a maximum amount of floor space but require long service runs and cannot serve as lateral bracing. 

  * Two cores may be symmetrically placed to reduce service runs and to serve effectively as lateral bracing, but the remaining floor area loses some flexibility in layout and use. 

  * Multiple cores are often used in broad, low-rise buildings in order to avoid long horizontal runs. 
  * The cores may be dispersed to better serve spaces or zones that have different demands and load requirements. 
  * In apartment buildings and other structures housing repetitive units, the cores may be situated between the units or along interior corridors. 

  * The service core or cores of a building house the vertical distribution of mechanical and electrical services, elevator shafts, and exit stairways.  These cores must be coordinated with the structural layout of columns, bearing walls, and shear walls or lateral bracing as well as with the desired patterns of space, use, and activity.  Shown above are some basic ways in which we can lay out the service cores of a building. 

## **11.21 AIR DISTRIBUTION OUTLETS**

Air for heating, cooling, and ventilating is supplied through registers and diffusers.  They should be evaluated in terms of their air-flow capacity and velocity, pressure drop, noise factor, and appearance. 

Air-supply outlets should be located to distribute warm or cool air to the occupied areas of a space comfortably, without noticeable drafts, and without stratification.  The throw distance and spread or diffusion pattern of the supply outlet should be carefully considered along with any obstructions that might interfere with the air distribution. 

**CSI MasterFormat 23 37 13: Diffusers, Registers, and Grilles**

## **11.22 WATER SUPPLY**

Water is used in a building in the following ways:

  * Water is consumed by drinking, cooking, and washing. 
  * HVAC systems circulate water for heating and cooling, and maintaining a desirable level of humidity. 
  * Fire-protection systems store water for extinguishing fires. 

Water must be supplied to a building in the correct quantity, and at the proper flow rate, pressure, and temperature, to satisfy the above requirements.  For human consumption, water must be potable—free of harmful bacteria—and palatable.  To avoid the clogging or corrosion of pipes and equipment, water may have to be treated for hardness or excessive acidity. 

If water is supplied by a municipal or public system, there can be no direct control over the quantity or quality of water supplied until it reaches the building site.  If a public water system is not available, then either drilled or bored wells or rainwater storage tanks are required. 

Well water, if the source is deep enough, is usually pure, cool, and free of discoloration and taste or odor problems.  A sample should be checked for bacteria and chemical content by the local health department before a well is put into operation. 

### **Private Well**

### **Public Water Supply**

**CSI MasterFormat 33 10 00: Water Utilities  
CSI MasterFormat 33 21 00: Water Supply Wells**

## **11.23 WATER SUPPLY SYSTEMS**

Water supply systems operate under pressure.  The service pressure of a water supply system must be great enough to absorb pressure losses due to vertical travel and friction as the water flows through pipes and fittings, and still satisfy the pressure requirement of each plumbing fixture.  Public water systems usually supply water at about 50 psi (345 kPa).  This pressure is the approximate upper limit for most private well systems. 

If water is supplied at 50 psi (345 kPa), upfeed distribution is feasible for low-rise buildings up to six stories in height.  For taller buildings, or where the water service pressure is insufficient to maintain adequate fixture service, water is pumped up to an elevated or rooftop storage tank for gravity downfeed.  Part of this water is often used as a reserve for fire-protection systems. 

There must be sufficient pressure at each fixture to ensure its satisfactory operation.  Fixture pressure requirements vary from 5 to 30 psi (35 to 207 kPa).  Too much pressure is as undesirable as insufficient pressure.  Water supply pipes are therefore sized to use up the differential between the service pressure, allowing for the pressure loss due to vertical lift or hydraulic friction, and the pressure requirement for each fixture.  If the supply pressure is too high, pressure reducers or regulators may be installed on plumbing fixtures. 

**CSI MasterFormat 22 00 00: Plumbing  
CSI MasterFormat 22 11 00: Facility Water Distribution**

## **11.24 WATER SUPPLY SYSTEMS**

Water supply lines may be of copper, galvanized steel, or plastic.  Copper piping is commonly used for water supply lines because of its corrosion resistance, strength, low friction loss, and small outside diameter.  Plastic pipes are lightweight, easily joined, produce low friction, and do not corrode, but not all types are suitable for carrying potable water.  Polybutylene (PB), polyethylene (PE), polyvinyl chloride (PVC), and chlorinated polyvinyl chloride (CPVC) pipes may be used for cold-water supply lines; only PB and CPVC are suitable for hot-water lines. 

Engel-method crosslinked polyethylene (PEX-A) tubing is suitable for both cold- and hot-water lines.  It is flexible, immune to corrosion and mineral buildup, retains more heat in hot-water lines, resists condensation in cold-water lines, and dampens water noise. 

Water pipes are sized according to the number and types of plumbing fixtures served and pressure losses due to hydraulic friction and static head.  Each type of fixture is assigned a number of fixture units.  Based on the total number of fixture units for a building, an equivalent demand in gallons per minute (gpm) is estimated.  Because it is assumed that not all fixtures will be used at the same time, the total demand is not directly proportional to the total load in fixture units. 

The water supply system can usually be accommodated within floor and wall construction spaces without too much difficulty.  It should be coordinated with the building structure and other systems, such as the parallel but bulkier sanitary drainage system. 

Water supply pipes should be supported at every story vertically and every 6′ to 10′ (1830 to 3050) horizontally.  Adjustable hangers can be used to ensure proper pitch along horizontal runs for drainage. 

Cold-water pipes should be insulated to prevent heat flow into the water from the warmer surrounding air.  Hot-water pipes should be insulated against heat loss and should be no closer than 6″ (150) to parallel cold-water pipes. 

In very cold climates, water pipes in exterior walls and unheated buildings can freeze and rupture.  Provision should be made for their drainage to a low point in the system where a drainage faucet is located. 

## **11.25 FIRE PROTECTION SYSTEMS**

Fire-alarm systems are installed in a building to automatically sound an alarm when actuated by a fire-detection system.  The fire-detection system may consist of heat sensors such as thermostats, or smoke detectors that are actuated by-products of combustion.  Most jurisdictions require the installation and hard-wiring of smoke detectors in residential occupancies and hotel/motel units.  Refer to the National Fire Protection Association's (NFPA's) Life Safety Code for recommendations concerning the type and placement of heat and smoke detectors. 

In large commercial and institutional buildings where public safety is an issue, building codes often require a fire sprinkler system; some codes allow an increase in floor area if an approved sprinkler system is installed.  Some jurisdictions require the installation of fire sprinkler systems in multifamily housing as well. 

Fire sprinkler systems consist of pipes that are located in or below ceilings, connected to a suitable water supply, and supplied with valves or sprinkler heads made to open automatically at a certain temperature.  The two major types of sprinkler systems are wet-pipe systems and dry-pipe systems. 

  * Wet-pipe systems contain water at sufficient pressure to provide an immediate, continuous discharge through sprinkler heads that open automatically in the event of a fire. 
  * Dry-pipe systems contain pressurized air that is released when a sprinkler head opens in the event of fire, allowing water to flow through the piping and out the opened nozzle.  Dry-pipe systems are used where the piping is subject to freezing. 
  * Preaction systems are dry-pipe sprinkler systems through which water flow is controlled by a valve operated by fire-detection devices more sensitive than those in the sprinkler heads.  Preaction systems are used when an accidental discharge would damage valuable materials. 
  * Deluge systems have sprinkler heads open at all times, through which water flow is controlled by a valve operated by a heat-, smoke-, or flame-sensing device. 

**CSI MasterFormat 21 00 00: Fire Suppression**

## **11.26 PLUMBING FIXTURES**

Plumbing fixtures receive water from a supply system and discharge the liquid waste into a sanitary drainage system.  They should be of a dense, smooth, nonabsorbent material, and be free of concealed fouling surfaces.  Some building codes mandate the use of water-efficient fixtures and valves in order to conserve water resources. 

### **Traps**

An essential feature of the sanitary drains from plumbing fixtures is a trap, a U-shaped or S-shaped section of drainpipe in which wastewater remains.  This wastewater forms a seal that prevents the passage of sewer gas without affecting the normal flow of wastewater or sewage through it. 

  * Every plumbing fixture requires a trap. 
  * Fixtures should have sufficient water flow to periodically clean out their traps and prevent sediment from collecting. 

  * See 9.27 for typical sizes of plumbing fixtures. 

**CSI MasterFormat 22 40 00: Plumbing Fixtures**

## **11.27 SANITARY DRAINAGE SYSTEMS**

The water supply system terminates at each plumbing fixture.  After water has been drawn and used, it enters the sanitary drainage system.  The primary objective of this drainage system is to dispose of fluid waste and organic matter as quickly as possible. 

Since a sanitary drainage system relies on gravity for its discharge, its pipes are much larger than the water supply lines, which are under pressure.  Drainage lines are sized according to their location in the system and the total number and types of fixtures served.  Always consult the plumbing code for allowable pipe materials, pipe sizing, and restrictions on the length and slope of horizontal runs and on the types and number of turns allowed. 

Drainage lines may be of cast iron or plastic.  Cast iron, the traditional material for drainage piping, may have hubless or bell-and-spigot joints and fittings.  The two types of plastic pipe that are suitable for drainage lines are polyvinyl chloride (PVC) and acrylonitrile-butadiene-styrene (ABS).  Some building codes also permit the use of galvanized wrought iron or steel. 

### **Maximum Pipe Sizes**

  * The plumbing or wet wall behind fixtures should be deep enough to accommodate branch lines, fixture runouts, and air chambers. 

**4″ (100) stud wall**

  * 3″ (75) ø hubless cast iron or plastic pipe
  * 2″ (51) ø bell-and-spigot cast iron pipe

**6″ (150) stud wall**

  * 5″ (125) ø hubless cast iron or plastic pipe
  * 3″ (75) ø bell-and-spigot cast iron pipe

**8″ (205) stud wall**

  * 6″ (150) ø hubless cast iron or plastic pipe
  * 5″ (125) ø bell-and-spigot cast iron pipe

### **Pipe Fittings**

  * Elbows have an angled bend, usually 45° or 90°. 

  * Drop elbow has lugs for attachment to a wall or joist. 

  * Closet bend is a 90° soil fitting installed directly beneath a water closet. 
  * Tees are T-shaped pipe fittings for making three-way joints. 

  * Drop tee has lugs for attachment to a wall or joist. 
  * Sanitary tees have a slight curve in the 90° transition to channel the flow from a branch pipe in the direction of the main. 

  * Wyes are Y-shaped pipe fittings for joining a branch pipe with a main, usually at a 45° angle. 

  * Nipples are short lengths of pipe with threads on each end, used for joining couplings or other pipe fittings. 

  * Couplings are short lengths of pipe having each end threaded on the inside, used for joining two pipes of the same diameter. 

  * Increaser is a coupling increasing in diameter at one end. 
  * Reducer is a coupling decreasing in diameter at one end. 

  * Unions connect two pipes neither of which can be turned, consisting of two internally threaded end pieces that are tightened around the pipe ends to be joined, and an externally threaded center piece, which draws the two end pieces together as it is rotated. 

  * Plugs are externally threaded fittings for closing the end of a pipe. 

  * Caps are internally threaded fittings for enclosing the end of a pipe. 

  * Bell-and-spigot pipe joints are made by fitting the end (spigot) of one pipe into the enlarged end (bell) of another pipe and sealing with a caulking compound or a compressible ring. 

**CSI MasterFormat 33 30 00: Sanitary Sewerage Utilities**

## **11.28 SANITARY DRAINAGE SYSTEMS**

The layout of the sanitary drainage system should be as direct and straightforward as possible to prevent the deposit of solids and clogging.  Cleanouts should be located to allow pipes to be easily cleaned if they do clog. 

### **Vents**

The vent system permits septic gases to escape to the outside and supplies a flow of fresh air into the drainage system to protect trap seals from siphonage and back pressure. 

**CSI MasterFormat 33 31 00: Sanitary Utility Sewerage Piping**

## **11.29 SEWAGE DISPOSAL SYSTEMS**

Sanitary sewers usually convey sewage from plumbing fixtures to a public facility for treatment and disposal.  When this is not possible, a private sewage disposal system is required.  Its type and size depend on the number of fixtures served and the permeability of the soil as determined by a percolation test.  Sewage disposal systems are designed by sanitary engineers and must be approved and inspected by the health department before being put into use.  Consult the building and health codes for specific regulations and requirements. 

**CSI MasterFormat 33 36 00: Utility Septic Tanks**

## **11.30 ELECTRIC POWER**

The electrical system of a building supplies power for lighting, heating, and the operation of electrical equipment and appliances.  This system must be installed according to the building and electrical codes in order to operate safely, reliably, and effectively.  All electrical equipment should meet Underwriters' Laboratories (UL) standards.  Consult the National Electrical Code for specific requirements in the design and installation of any electrical system. 

Electrical energy flows through a conductor because of a difference in electrical charge between two points in a circuit. 

  * Volt (V) is the SI unit of electromotive force, defined as the difference of electric potential between two points of a conductor carrying a constant current of one ampere, when the power dissipated between the points is equal to one watt. 
  * Ampere (A) is the basic SI unit of electric current, equivalent to a flow of one coulomb per second or to the steady current produced by one volt applied across a resistance of one ohm. 
  * Watt (W) is the SI unit of power, equal to one joule per second or to the power represented by a current of one ampere flowing across a potential difference of one volt. 
  * Ohm is the SI unit of electrical resistance, equal to the resistance of a conductor in which a potential difference of one volt produces a current of one ampere.  Symbol: Ω

Power is usually supplied to a building by the electric utility company.  The schematic diagram below illustrates several voltage systems that may be furnished by the public utility according to the load requirements of a building.  A large installation may use its own transformer to step down from a more economical, higher supply voltage to the service voltage.  Generator sets may be required to supply emergency electrical power for exit lighting, alarm systems, elevators, telephone systems, fire pumps, and medical equipment in hospitals. 

**Hydraulic Analogy to Electric Circuit**

**CSI MasterFormat 33 70 00: Electrical Utilities**

## **11.31 ELECTRICAL SERVICE**

The public utility company should be notified of the estimated total electrical load requirements for a building during the planning phase to confirm service availability and to coordinate the location of the service connection and meter. 

The service connection may be overhead or underground.  Overhead service is less expensive, easily accessible for maintenance, and can carry high voltages over long runs.  Underground service is more expensive but is used in high load-density situations such as urban areas.  The service cables are run in pipe conduit or raceways for protection and to allow for future replacement.  Direct burial cable may be used for residential service connections. 

**CSI MasterFormat 26 05 26: Grounding and Bonding for Electrical Systems**

## **11.32 ELECTRICAL SERVICE**

### **Photovoltaic Technology**

  * Net metering is a policy of some public utilities that promotes investment in renewable energy–generating technologies by allowing customers to offset their consumption over a billing period when they generate electricity in excess of their demand. 

### **Building-Integrated Photovoltaics**

Second-generation thin-film solar cells are made from amorphous silicon or nonsilicon materials such as cadmium telluride.  Because of their flexibility, thin-film solar cells can be incorporated into the roof, walls, or windows of a building as either a principal or ancillary source of electrical power, often replacing conventional building materials.  They can be can be integrated with flexible roofing membranes, shaped and used as roofing shingles or tiles, serve as components of a curtain-wall system, or used for the glazing of skylights. 

LEED EA Credit 2: On-site Renewable Energy

**CSI MasterFormat 48 14 13: Solar Energy Collectors**

## **11.33 ELECTRICAL CIRCUITS**

Once the electrical power requirements for the various areas of a building are determined, wiring circuits must be laid out to distribute the power to the points of utilization. 

  * Load requirements for lighting fixtures and electrically powered appliances and equipment are specified by their manufacturer.  The design load for a general purpose circuit, however, depends on the number of receptacles served by the circuit and how they are used.  Consult the National Electrical Code for requirements. 

  * Separate wiring circuits are required for the sound and signal equipment of telephone, cable, intercom, and security or fire alarm systems. 
  * Telephone systems should have their outlets located and wired during construction.  Large installations also require a service connection, terminal enclosures, riser spaces, etc.,  similar to electrical systems.  Large systems are usually designed, furnished, and installed by a telecommunications company. 
  * Cable television systems may receive their signals from an outdoor antenna or satellite dish, a cable company, or a closed circuit system.  If several outlets are required, a 120 V outlet is supplied to serve an amplifier.  Coaxial cables in a nonmetallic conductor raceway transmit the amplified signal to the various outlets. 

**CSI MasterFormat 26 10 00: Medium-Voltage Electrical Distribution  
CSI MasterFormat 26 18 00: Medium-Voltage Circuit Protection Devices**

## **11.34 ELECTRICAL WIRING**

Metals, offering little resistance to the flow of electric current, make good conductors.  Copper is most often used.  The various forms of conductors—wire, cable, and busbars—are sized according to their safe current-carrying capacity and the maximum operating temperature of their insulation.  They are identified according to:

A conductor is covered with insulation to prevent its contact with other conductors or metal, and to protect it against heat, moisture, and corrosion.  Materials with a high resistance to the flow of electric current, such as rubber, plastics, porcelain, and glass are commonly used to insulate electrical wiring and connections. 

Conduit provides support for wires and cables and protects them against physical damage and corrosion.  Metal conduit also provides a continuous grounded enclosure for the wiring.  For fireproof construction, rigid metal conduit, electrical metallic tubing, or flexible metal conduit can be used.  For frame construction, armored or nonmetallic sheathed cable is used.  Plastic tubing and conduits are most commonly used for underground wiring. 

Being relatively small, conduit can be easily accommodated in most construction systems.  Conduit should be adequately supported and laid out as directly as possible.  Codes generally restrict the radius and number of bends a run of conduit may have between junction or outlet boxes.  Coordination with a building's mechanical and plumbing systems is required to avoid conflicting paths. 

Electrical conductors are often run within the raceways of cellular steel decking to allow for the flexible placement of power, signal, and telephone outlets in office buildings.  Flat conductor cable systems are also available for installation directly under carpet tiles. 

For exposed installations, special conduit, raceways, troughs, and fittings are available.  As with exposed mechanical systems, the layout should be visually coordinated with the physical elements of the space. 

**CSI MasterFormat 26 05 00: Common Work Results for Electrical**

## **11.35 ACCESS FLOORING SYSTEMS**

Access flooring systems are typically used in office spaces, hospitals, laboratories, computer rooms, and television and communication centers to provide accessibility and flexibility in the placement of desks, workstations, and equipment.  Equipment can be moved and reconnected fairly easily with modular wiring systems. 

**CSI MasterFormat 09 69 00: Access Flooring**

## **11.36 ELECTRICAL OUTLETS**

Lighting fixtures, wall switches, and convenience outlets are the most visible parts of an electrical system.  Switches and receptacle outlets should be located for convenient access, and coordinated with visible surface patterns.  Wall plates for these devices may be of metal, plastic, or glass, and are available in a variety of colors and finishes. 

The design load for a general purpose circuit depends on the number of outlets served by the circuit and how they are used.  Consult the National Electrical Code for calculating the required number and spacing of convenience outlets. 

### **Heights of Switches and Outlets**

### **Switches**

  * Toggle switch has a lever or knob that moves through a small arc and causes the contacts to open or close an electric circuit. 

  * Dimmer is a rheostat or similar device for regulating the intensity of an electric light without appreciably affecting spatial distribution. 

### **Number of Convenience Outlets**

**Residences**

  * One outlet every 12′ (3660) along walls in a living space
  * One outlet every 4′ (1220) along countertops in kitchens
  * One GFI-protected outlet in bathrooms

**Offices**

  * One outlet every 10′ (3050) along walls, or
  * One outlet every 40 sf (3.7 m2) of floor area for the first 400 sf (37 m2) and one outlet for every 100 sf (9.3 m2) thereafter

### **Receptacles**

### **Typical Electrical Plan Symbols**

## **11.37 LIGHT**

## **11.38 LIGHT & VISION**

Light reveals to our eyes the shape, texture, and color of objects in space.  An object in its path will reflect, absorb, or allow the light striking its surface to pass through.  Luminance is the quantitative measure of brightness of a light source or an illuminated surface, equal to the luminous intensity per unit projected area of the source or surface viewed from a given direction. 

Brightness is the sensation by which an observer is able to distinguish between differences in luminance.  Visual acuity increases with object brightness.  Of equal importance is the ratio of the luminance of an object being viewed and that of its background.  To discern shape and form, some degree of contrast or brightness ratio is required.  Contrast is especially critical for visual tasks that require discrimination of shape and contour.  For seeing tasks requiring discrimination of texture and detail, less contrast is desirable since our eyes adjust automatically to the average brightness of a scene.  When the contrast or brightness ratio is too high, glare can result. 

  * Lambert is a unit of luminance or brightness equal to 0.32 candela per square centimeter. 
  * Foot-lambert is a unit of luminance or brightness equal to 0.32 candela per square foot. 
  * Brightness is affected by both color and texture.  Shiny, light-colored surfaces reflect more light than dark, matte or rough-textured surfaces, even though both surfaces may receive the same amount of illumination. 

Glare is the sensation produced by any brightness within the visual field that is sufficiently greater than the luminance to which the eyes are adapted to cause annoyance, discomfort, or loss of visibility.  There are two types of glare: direct and reflected. 

## **11.39 LIGHT SOURCES**

Artificial light is natural light that is produced by manufactured elements.  The quantity and quality of light produced differ according to the type of lamp used.  The light is further modified by the housing that holds and energizes the lamp.  There are three major types of artificial light sources—incandescent, fluorescent, and high-intensity discharge (HID) lamps.  For accurate, current data on lamp sizes, wattages, lumen output, and average life, consult the lamp manufacturer. 

### **Incandescent Lamps**

Incandescent lamps contain a filament that gives off light when heated to incandescence by the passage of an electric current.  They provide point sources of light, have low efficacy, render color well, and are easy to dim with rheostats. 

  * Efficacy is a measure of the effectiveness with which a lamp converts electric power into luminous flux, equal to the ratio of flux emitted to power input and expressed in lumens per watt. 
  * Rated life is the average life in hours of a given type of lamp, based on laboratory tests of a representative group under controlled conditions. 
  * Extended-service lamps are designed for reduced energy consumption and a life longer than the conventional value for its general class. 
  * Three-way lamp is an incandescent lamp having two filaments so that it can be switched to three successive degrees of illumination. 

**CSI MasterFormat 26 51 13: Interior Lighting Fixtures, Lamps, and Ballasts**

## **11.40 LIGHT SOURCES**

Discharge lamps produce light by the discharge of electricity between electrodes in a gas-filled glass enclosure.  The two major types of discharge lamps are fluorescent lamps and a variety of high-intensity discharge lamps. 

### **Fluorescent Lamps**

Fluorescent lamps are tubular low-discharge lamps in which light is produced by the fluorescence of phosphors coating the inside of the tube.  Because fluorescent lamps contain mercury, they require special handling for recycling.  The amount of mercury used continues to be reduced, and T5 lamps now have low mercury content. 

Fluorescent lamps are more efficient and have a longer life (6,000–24,000+ hours) than incandescent lamps.  They produce little heat and are available in a variety of types and wattages.  Common lengths range from a 6″ (150) 4-watt T5 to an 8′ (2440) 125-watt T12.  Fluorescent lamps require a ballast to regulate electric current through the lamp.  Some lamps have pin bases, while others have screw-in bases. 

  * Ballasts maintain the current through a fluorescent or high-intensity discharge lamp at the desired constant value. 
  * Preheat lamps require a separate starter to preheat the cathodes before opening the circuit to the starting voltage. 
  * Rapid-start lamps are designed to operate with a ballast having a low-voltage winding for continuous heating of the cathodes, which allows the lamps to be started more rapidly than a preheat lamp. 
  * Instant-start lamps are designed to operate with a ballast having a high-voltage transformer to initiate the arc directly without any preheating of the cathodes. 
  * High-output lamps are rapid-start fluorescent lamps designed to operate on a current of 800 milliamperes, resulting in a corresponding increase in luminous flux per unit length of lamp. 
  * Very-high-output lamps are designed to operate on a current of 1500 milliamperes, providing a corresponding increase in luminous flux per unit length of lamp. 

Compact fluorescent lamps are any of various small, improved-efficiency fluorescent lamps having a single, double, or U-shaped tube, and often an adapter for fitting an incandescent lampholder. 

  * Available from 5 to 80 watts. 
  * High efficacy (typically 60 to 72 lumens per watt). 
  * Good color rendering. 
  * Very long lives (6000 to 15,000 hours). 
  * Tubular or spiral types. 
  * Many are available with built-in ballast and screw bases for direct replacement of incandescent lamps. 

## **11.41 LIGHT SOURCES**

### **High-Intensity Discharge Lamps**

High-intensity discharge (HID) lamps are discharge lamps in which a significant amount of light is produced by the discharge of electricity through a metallic vapor in a sealed glass enclosure.  HID lamps combine the form of an incandescent lamp with the efficacy of a fluorescent. 

  * Mercury lamps produce light by means of an electric discharge in mercury vapor. 
  * Metal-halide lamps are similar in construction to a mercury lamp, but have an arc tube to which various metal halides are added to produce more light and improve color rendering. 
  * High-pressure sodium (HPS) lamps produce a broad spectrum of golden-white light by means of an electric discharge in sodium vapor. 

### **Light and Color**

The spectral distribution of artificial light varies with the type of lamp.  For example, an incandescent bulb produces a yellow-white light while a cool-white fluorescent produces a blue-white light.  The spectral distribution of a light source is important because if certain wavelengths of color are missing, then those colors cannot be reflected and will appear to be missing in any surface illuminated by that light. 

  * Color rendering index is a measure of the ability of an electric lamp to render color accurately when compared with a reference light source of similar color temperature.  A tungsten lamp operating at a color temperature of 3200°K, noon sunlight having a color temperature of 4800°K, and average daylight having a color temperature of 7000°K all have an index of 100 and are considered to render color perfectly. 

### **Color Rendering Index (CRI) of Various Light Sources**

**CRI** | **Light Source**  
---|---  
100 | Noon sunlight; average daylight  
93 | 500-watt incandescent  
89 | Cool-white deluxe fluorescent  
78 | Warm-white deluxe fluorescent  
62 | Cool-white fluorescent  
52 | Warm-white fluorescent

### **Correlated Color Temperature (CCT)**

**CCT in °Kelvins** | **Light Source**  
---|---  
2700 | Incandescent  
3000 | Halogen  
2700–6500 | Fluorescent  
3000–4000 | Metal halide  
2800–6000 | LED  
5500–7500 | Daylight

  * Spectral distribution curves plot the radiant energy in each wavelength of a particular light source. 

## **11.42 LIGHT SOURCES**

### **Fiber Optics**

The optical glass or plastic fibers in fiber-optic lighting transmit light from one end to the other by reflecting light rays back and forth inside their cores in a zigzag pattern.  Each small-diameter fiber is protected by a transparent sheath and combined with others into flexible bundles. 

### **Light-Emitting Diodes**

Light-emitting diodes (LEDs) radiate very little heat and are highly energy-efficient.  LEDs have an extremely long life, typically about ten years.  High-powered white-light LEDs are used for illumination.  They are insensitive to vibration and temperature, are shock-resistant, and contain no mercury.  The tiny 1/8″ (3.2) lamps can be combined into larger groups to mix colors and increase illumination.  LEDs operate on DC voltage, which is transformed into AC voltage within the fixture. 

LEDs are used for both residential and commercial lighting.  They can be designed to focus light, and are widely used for task lights.  LED downlights, step lighting, and exit signs are also available. 

LED step lighting

## **11.43 LUMINAIRES**

A luminaire, also commonly called a lighting fixture, consists of one or more electric lamps with all of the necessary parts and wiring for positioning and protecting the lamps, connecting the lamps to a power supply, and distributing the light. 

  * Lens of glass or plastic have two opposite surfaces either or both of which are curved.  They are used in luminaires to focus, disperse, or collimate the emitted light. 

  * In order to evaluate problems with direct glare, the visual comfort probability factor was developed.  It rates the likelihood that a lighting system will not cause direct glare, expressed as the percentage of people who may be expected to experience visual comfort when seated in the least-favorable visual position. 

**CSI MasterFormat 26 51 13: Interior Lighting Fixtures, Lamps, and Ballasts**

## **11.44 LIGHTING**

The primary purpose of a lighting system is to provide sufficient illumination for the performance of visual tasks.  Recommended levels of illumination for certain tasks specify only the quantity of light to be supplied.  How this amount of light is supplied affects how a space is revealed or how an object is seen. 

### **Recommended Illumination Levels**

Diffused light emanates from broad or multiple light sources and reflecting surfaces.  The flat, fairly uniform illumination minimizes contrast and shadows and can make the reading of textures difficult. 

Directional light, on the other hand, enhances our perception of shape, form, and texture by producing shadows and brightness variations on the surfaces of the objects illuminated. 

While diffused lighting is useful for general vision, it can be monotonous.  Some directional lighting can help relieve this dullness by providing visual accents, introducing variations in luminance, and brightening task surfaces.  A mix of both diffused and directional lighting is often desirable and beneficial, especially when a variety of tasks are to be performed. 

Luminaires may be categorized according to the percentage of light emitted above and below a horizontal plane.  The actual light distribution of a specific luminaire is determined by the type of lamp, lens, and reflector housing used.  Consult the luminaire manufacturer for candlepower distribution curves. 

### **General Diffuse**

  * 40% to 60%
  * 40% to 60%

### **Direct-Indirect**

  * 40% to 60%
  * 40% to 60%

### **Semidirect**

  * 10% to 40%
  * 60% to 90%

### **Semi-Indirect**

  * 60% to 90%
  * 10% to 40%

### **Indirect**

  * 90% to 100%
  * 0% to 10%

### **Direct**

  * 0% to 10%
  * 90% to 100%

### **Brightness Ratios**

  * 3:1 is the maximum recommended brightness ratio between the visual task area (A) and its immediate background (B). 
  * The surrounding area (C) should range from ⅕ to five times the brightness of the visual task area (A). 

**CSI MasterFormat 26 51 00: Interior Lighting**

## **11.45 LIGHTING**

### **Daylight Harvesting**

Daylight harvesting is a method of lighting control that reduces energy consumption by using photosensors to detect daylighting levels and automatically adjusting the output level of electric lighting to create the desired or recommended level of illumination for a space.  If the daylighting from windows is sufficient to meet users' needs, the lighting control system can automatically turn off all or a portion of the electric lighting or dim the lighting, and immediately reactivate the lighting if the daylighting falls below a preset level.  Daylight harvesting controls can be integrated with occupancy sensors for automated on/off control to further increase energy savings as well as with manual override controls to allow for adjustment of lighting levels by occupants.  Some control systems can also adjust the color balance of the light by varying the intensity of individual LED lamps of different colors installed in the overhead fixtures. 

### **Bi-Level Switching**

Bi-level switching is a lighting control system that provides two levels of lighting power in a space, not including off.  The switching system may control alternate ballasts or lamps in a luminaire, alternate luminaires, or alternate lighting circuits independently by such means as: photosensors that detect the light level from available daylighting; occupancy sensors that detect user presence; time-based control panels; or manual switches controllable by occupants or the facility operator.  Many energy codes in the United States require light-level reduction controls, such as bi-level switching, in enclosed spaces of certain occupancies. 

### **Multi-Level Switching**

A form of bi-level switching in which multiple lamps in a single light fixture can be switched on and off independently of each other, allowing for one or two steps between full output and zero illumination while maintaining the required uniform distribution of light suitable for work.  For example, a series of three-lamp fixtures with split-ballast wiring can provide four light levels: 100% (all lamps lit), 66% (2 lamps in each fixture lit), 33% (1 lamp in each fixture lit), and 0% (all lamps extinguished).  Multi-level switching provides greater flexibility and lessens the abrupt changes in light level of bi-level switching. 

### **Continuous Dimming**

Continuous dimming is a method of lighting control that maintains the desired or recommended level of illumination for a space by modulating the output from electric lamps and fixtures in proportion to the amount of available daylight detected by light-level sensors.  Continuous dimming systems minimize the abrupt changes in light level created by bi-level and multi-level switching systems. 

### **Occupancy Control**

Occupancy controls are automatic lighting control systems that use motion or occupancy sensors to turn lights on when human activity is detected and turn lights off when a space is vacated.  Occupancy sensors can replace wall-mounted light switches or can be mounted remotely, retaining the normal switching for use as override switches, which allows the lighting to be kept off even when the space is occupied. 

LEED IEQ Credit 6.1: Controllability of Systems, Lighting

## **11.46 LIGHTING**

  * Beam spread is the angle of a light beam that intersects the candlepower distribution curve at points where the luminous intensity equals a stated percent of a maximum reference intensity. 

Spacing criteria is a formula for determining how far apart luminaires may be installed for uniform lighting of a surface or area, based on mounting height. 

The point method is a procedure for calculating the illumination produced on a surface by a point source from any angle, based on the inverse square and cosine laws. 

  * Ceiling cavity is formed by a ceiling, a plane of suspended luminaires, and wall surfaces between these two planes. 
  * Room cavity is formed by a plane of luminaires, the work plane, and the wall surfaces between these two planes. 
  * Floor cavity is formed by the work plane, the floor, and the wall surfaces between these two planes. 

The lumen method, also called the zonal cavity method, is a procedure for determining the number and types of lamps, luminaires, or windows required to provide a uniform level of illumination on a work plane, taking into account both direct and reflected luminous flux. 

  * Work plane is the horizontal plane at which work is done and on which illumination is specified and measured, usually assumed to be 30″ (762) above the floor. 

LEED EQ Credit 6.1: Controllability of Lighting Systems

# **Chapter 12**  
 **NOTES ON MATERIALS**

12.02 Building Materials

12.03 Life-Cycle Assessment

12.04 Concrete

12.06 Masonry

12.08 Steel

12.09 Nonferrous Metals

12.10 Stone

12.11 Wood

12.13 Lumber

12.14 Wood Panel Products

12.15 Plastics

12.16 Glass

12.17 Glass Products

12.18 Nails

12.19 Screws & Bolts

12.20 Miscellaneous Fastenings

12.21 Paints & Coatings

## **12.02 BUILDING MATERIALS**

This chapter describes the major types of building materials, their physical properties, and their uses in building construction.  The criteria for selecting and using a building material include those listed below. 

  * Each material has distinct properties of strength, elasticity, and stiffness.  The most effective structural materials are those that combine elasticity with stiffness. 

  * Stiffness is a measure of the extent to which an elastic body resists deformation.  The stiffness of a solid body is dependent on its structural shape as well as the elasticity of its material and is an important factor when considering the relationship between span and deflection under loading. 

  * The dimensional stability of a material as it responds to changes in temperature and moisture content affects the manner in which it is detailed and constructed to join with other materials. 
  * The resistance of a material to water and water vapor is an important consideration when it is exposed to weather or used in moist environments. 
  * The thermal conductivity or resistance of a material must be assessed when it is used in constructing the exterior envelope of a building. 

  * A material's transmission, reflection, or absorption of visible light and radiant heat should be evaluated when the material is used to finish the surfaces of a room. 
  * The density or hardness of a material determines its resistance to wear and abrasion, its durability in use, and the costs required to maintain it. 

  * The ability of a material to resist combustion, withstand exposure to fire, and not produce smoke and toxic gases, must be evaluated before using it as a structural member or an interior finish. 

  * The color, texture, and scale of a material are obvious considerations in evaluating how it fits within the overall design scheme. 
  * Many building materials are manufactured in standard shapes and sizes.  These stock dimensions, however, may vary slightly from one manufacturer to the next.  They should be verified in the planning and design phases of a building so that unnecessary cutting or wasting of material can be minimized during construction. 

## **12.03 LIFE-CYCLE ASSESSMENT**

The evaluation of building materials should extend beyond their functional, economic, and aesthetic aspects and include assessing the environmental consequences associated with their selection and use.  This examination, called a life-cycle assessment, encompasses the extraction and processing of raw materials, the manufacturing, packaging, and transportation of the finished product to the point of use, maintaining the material in use, the possible recycling and reuse of the material, and its final disposal.  This assessment process consists of three components: inputs, life-cycle inventory, and outputs. 

  * Embodied energy includes all of the energy expended during the life cycle of a material. 
  * Refer to the Environmental Resource Guide, a project of the American Institute of Architects, for more information. 

### **Embodied Energy in Building Materials**

### **Life-Cycle Inventory**

Evaluating the choice of a building material is a complex matter that cannot be reduced to a simple formula yielding a precise and valid answer with certainty.  For example, using less of a material with a high energy content may be more effective in conserving energy and resources than using more of a lower-energy material.  Using a higher-energy material that will last longer and require less maintenance, or one that can be recycled and reused, may be more compelling than using a lower-energy material. 

Reduce, reuse, and recycle best summarize the kinds of strategies that are effective in achieving the goal of sustainability. 

  * Reduce building size through more efficient layout and use of spaces. 
  * Reduce construction waste.  LEED® MR Credit 2: Construction Waste Management
  * Specify products that use raw materials more efficiently.  LEED MR Credit 5: Regional Materials
  * Substitute plentiful resources for scarce resources.  LEED MR Credit 6: Rapidly Renewable Materials
  * Reuse building materials from demolished buildings.  LEED MR Credit 3: Materials Reuse
  * Rehabilitate existing buildings for new uses.  LEED MR Credit 1: Building Reuse
  * Recycle new products from old.  LEED MR Credit 3: Materials Reuse

## **12.04 CONCRETE**

Concrete is made by mixing cement and various mineral aggregates with sufficient water to cause the cement to set and bind the entire mass.  While concrete is inherently strong in compression, steel reinforcement is required to handle tensile and shear stresses.  It is capable of being formed into almost any shape with a variety of surface finishes and textures.  In addition, concrete structures are relatively low in cost and inherently fire-resistant.  Concrete's liabilities include its weight—150 pcf (2400 kg/m3) for normal reinforced concrete—and the forming or molding process that is required before it can be placed to set and cure. 

**CSI MasterFormat™ Division 03: Concrete**

## **12.05 CONCRETE**

### **Water-Cement Ratio**

Water-cement ratio is the ratio of mixing water to cement in a unit volume of a concrete mix, expressed by weight as a decimal fraction or as gallons of water per sack of cement.  The water-cement ratio controls the strength, durability, and watertightness of hardened concrete.  According to Abrams' law, formulated by D. A. Abrams in 1919 from experiments at the Lewis Institute in Chicago, the compressive strength of concrete is inversely proportional to the ratio of water to cement.  If too much water is used, the concrete mix will be weak and porous after curing.  If too little water is used, the mix will be dense but difficult to place and work.  For most applications, the water-cement ratio should range from 0.45 to 0.60. 

Concrete is normally specified according to the compressive strength it will develop within 28 days after placement (7 days for high-early-strength concrete). 

  * Compression test for determining the compressive strength of a concrete batch uses a hydraulic press to measure the maximum load a test cylinder 6″ (150) ø and 12″ (305) high can support in axial compression before fracturing. 

### **Steel Reinforcement**

Because concrete is relatively weak in tension, reinforcement consisting of steel bars, strands, or wires is required to absorb tensile, shearing, and sometimes the compressive stresses in a concrete member or structure.  Steel reinforcement is also required to tie vertical and horizontal elements, reinforce the edges around openings, minimize shrinkage cracking, and control thermal expansion and contraction.  All reinforcement should be designed by a qualified structural engineer. 

  * Reinforcing steel must be protected by the surrounding concrete against corrosion and fire.  Minimum requirements for cover and spacing are specified by the American Concrete Institute (ACI) Building Code Requirements for Reinforced Concrete according to the concrete's exposure, and the size of the coarse aggregate and steel used. 

  * For minimum coverage of steel reinforcement in other concrete members, see 3.08 for spread footings, 4.04 for concrete beams, 5.04 for concrete columns, and 5.06 for concrete walls. 

  * Welded wire fabric consists of a grid of steel wires or bars welded together at all points of intersection.  The fabric is typically used to provide temperature reinforcement for slabs but the heavier gauges can also be used to reinforce concrete walls.  The fabric is designated by the size of the grid in inches followed by a number indicating the wire gauge or cross-sectional area; see 3.18 for typical sizes. 

### **ASTM Standard Reinforcing Bars**

## **12.06 MASONRY**

Masonry refers to building with units of various natural or manufactured products, such as brick, stone, or concrete block, usually with the use of mortar as a bonding agent.  The modular aspect (i.e., uniform sizes and proportional relationships) of unit masonry distinguishes it from most of the other building materials discussed in this chapter.  Because unit masonry is structurally most effective in compression, the masonry units should be laid up in such a way that the entire masonry mass acts as an entity. 

### **Brick**

Brick is a masonry unit of clay, formed into a rectangular prism while plastic and hardened by firing in a kiln or drying in the sun. 

  * Soft-mud process refers to forming brick by molding relatively wet clay having a moisture content of 20% to 30%. 
  * Sandstruck brick is formed in the soft-mud process with a mold lined with sand to prevent sticking, producing a matte-textured surface. 
  * Waterstruck brick is formed in the soft-mud process with a mold lubricated with water to prevent sticking, producing a smooth, dense surface. 
  * Stiff-mud process refers to forming brick and structural tile by extruding stiff but plastic clay having a moisture content of 12% to 15% through a die and cutting the extrusion to length with wires before firing. 
  * Dry-press process refers to forming brick by molding relatively dry clay having a moisture content of 5% to 7% under high pressure, resulting in sharp-edged, smooth-surfaced bricks. 

### **Brick Types**

  * Brick type designates the permissible variation in size, color, chippage, and distortion allowed in a face brick unit. 
  * FBX is face brick suitable for use where a minimum variation in size, narrow color range, and high degree of mechanical perfection are required. 
  * FBS is face brick suitable for use where a wider color range and greater variation in size are permitted than for type FBX. 
  * FBA is face brick suitable for use where particular effects are desired resulting from nonuniformity in size, color, and texture of the individual units. 

  * Efflorescence is a white, powdery deposit that forms on an exposed masonry or concrete surface, caused by the leaching and crystallization of soluble salts from within the material.  Reducing moisture absorption is the best assurance against efflorescence. 

### **Brick Grades**

  * Brick grade designates the durability of a brick unit when exposed to weathering.  The United States is divided into three weathering regions—severe, moderate, and negligible—according to annual winter rainfall and the annual number of freezing-cycle days.  Brick is graded for use in each region according to compressive strength, maximum water absorption, and maximum saturation coefficient. 
  * SW is brick suitable for exposure to severe weathering, as when in contact with the ground or used on surfaces likely to be permeated with water in subfreezing temperatures; minimum compressive strength of 2500 psi (17,235 kPa). 
  * MW is brick suitable for exposure to moderate weathering, as when used above grade on surfaces unlikely to be permeated with water in subfreezing temperatures; minimum compressive strength of 2200 psi (15,167 kPa). 
  * NW is brick suitable for exposure to negligible weathering, as when used as a backup or in interior masonry; minimum compressive strength of 1250 psi (8,618 kPa). 
  * The allowable compressive stresses in masonry walls are much less than the values given here because the quality of the masonry units, mortar, and workmanship may vary.  See table on 5.15 for these values. 

  * See 5.26 for modular brick coursing and 5.27 for masonry bonding patterns. 

**CSI MasterFormat 04 21 00: Clay Unit Masonry**

## **12.07 MASONRY**

### **Concrete Masonry**

Concrete masonry units (CMU) are precast of portland cement, fine aggregate, and water, molded into various shapes to satisfy various construction conditions.  The availability of these types varies with locality and manufacturer. 

### **CMU Grades**

  * Grade N is a loadbearing concrete masonry unit suitable for use both above and below grade in walls exposed to moisture or weather; grade N units have a compressive strength from 800 to 1500 psi (5516 to 10,342 kPa). 
  * Grade S is a loadbearing concrete masonry unit limited to use above grade, in exterior walls with weather-protective coatings, or in walls not exposed to moisture or weather; grade S units have a compressive strength from 600 to 1000 psi (4137 to 6895 kPa). 

### **CMU Types**

  * Type I is a concrete masonry unit manufactured to a specified limit of moisture content in order to minimize the drying shrinkage that can cause cracking. 
  * Type II is a concrete masonry unit not manufactured to a specified limit moisture content. 

  * Concrete brick is a solid rectangular concrete masonry unit usually identical in size to a modular clay brick but also available in 12″ (305) lengths; concrete brick units have a compressive strength from 2000 to 3000 psi (13,790 to 20,685 kPa). 

**CSI MasterFormat 04 22 00: Concrete Unit Masonry**

## **12.08 STEEL**

Steel refers to any of various iron-based alloys having a carbon content less than that of cast iron and more than that of wrought iron, and having qualities of strength, hardness, and elasticity varying according to composition and heat treatment.  Steel is used for light and heavy structural framing, as well as a wide range of building products such as windows, doors, hardware, and fastenings.  As a structural material, steel combines high strength and stiffness with elasticity.  Measured in terms of weight to volume, it is probably the strongest low-cost material available.  Although classified as an incombustible material, steel becomes ductile and loses its strength when subject to temperatures over 1000°F (538°C).  When used in buildings requiring fire-resistive construction, structural steel must be coated, covered, or enclosed with fire-resistant materials; see A.12.  Because it is normally subject to corrosion, steel must be painted, galvanized, or chemically treated for protection against oxidation. 

### **Steel Shapes**

  * Refer to the American Institute of Steel Construction (AISC) Manual of Steel Construction for complete listing of sizes and weights. 

  * Carbon steel is unalloyed steel in which the residual elements, such as carbon, manganese, phosphorus, sulfur, and silicon, are controlled.  Any increase in carbon content increases the strength and hardness of the steel but reduces its ductility and weldability. 

  * Mild or soft steel is a low-carbon steel containing from 0.15% to 0.25% carbon. 
  * Medium steel is a carbon steel containing from 0.25% to 0.45% carbon; most structural steel is medium-carbon steel; ASTM A36 is the most common strength grade with a yield point of 36,000 psi (248,220 kPa). 
  * Hard steel is a high-carbon steel containing from 0.45% to 0.85% carbon. 
  * Spring steel is a high-carbon steel containing 0.85% to 1.8% carbon. 

  * Alloy steel refers to a carbon steel to which various elements, such as chromium, cobalt, copper, manganese, molybdenum, nickel, tungsten, or vanadium, have been added in a sufficient amount to obtain particular physical or chemical properties. 

  * Stainless steel contains a minimum of 12% chromium, sometimes with nickel, manganese, or molybdenum as additional alloying elements, so as to be highly resistant to corrosion. 
  * High-strength low-alloy steel is a low-carbon steel containing less than 2% alloys in a chemical composition specifically developed for increased strength, ductility, and resistance to corrosion; ASTM A572 is the most common strength grade with a yield point of 50,000 psi (344,750 kPa). 
  * Weathering steel is a high-strength, low-alloy steel that forms an oxide coating when exposed to rain or moisture in the atmosphere; this coating adheres firmly to the base metal and protects it from further corrosion.  Structures using weathering steel should be detailed to prevent the small amounts of oxide carried off by rainwater from staining adjoining materials. 
  * Tungsten steel is an alloy steel containing 10% to 20% tungsten for increased hardness and heat retention at high temperatures. 

Other ferrous metals used in building construction include:

  * Cast iron, a hard, brittle, nonmalleable iron-based alloy containing 2.0% to 4.5% carbon and 0.5% to 3% silicon, cast in a sand mold and machined to make many building products, such as piping, grating, and ornamental work
  * Malleable cast iron, which has been annealed by transforming the carbon content into graphite or removing it completely
  * Wrought iron, a tough, malleable, relatively soft iron that is readily forged and welded, having a fibrous structure containing approximately 0.2% carbon and a small amount of uniformly distributed slag
  * Galvanized iron, which is coated with zinc to prevent rust

**CSI MasterFormat 05 12 00: Structural Steel Framing**

## **12.09 NONFERROUS METALS**

Nonferrous metals contain no iron.  Aluminum, copper, and lead are nonferrous metals commonly used in building construction. 

Aluminum is a ductile, malleable, silver-white metallic element that is used in forming many hard, light alloys.  Its natural resistance to corrosion is due to the transparent film of oxide that forms on its surface; this oxide coating can be thickened to increase corrosion resistance by an electrical and chemical process known as anodizing.  During the anodizing process, the naturally light, reflective surface of aluminum can be dyed a number of warm, bright colors.  Care must be taken to insulate aluminum from contact with other metals to prevent galvanic action.  It should also be isolated from alkaline materials such as wet concrete, mortar, and plaster. 

Aluminum is widely used in extruded and sheet forms for secondary building elements such as windows, doors, roofing, flashing, trim, and hardware.  For use in structural framing, high-strength aluminum alloys are available in shapes similar to those of structural steel.  Aluminum sections may be welded, bonded with adhesives, or mechanically fastened. 

Copper is a ductile, malleable metallic element that is widely used for electrical wiring, water piping, and in the manufacture of alloys, as bronze and brass.  Its color and resistance to corrosion also make it an excellent roofing and flashing material.  However, copper will corrode aluminum, steel, stainless steel, and zinc.  It should be fastened, attached, or supported only with copper or carefully selected brass fittings.  Contact with red cedar in the presence of moisture will cause premature deterioration of the copper. 

Brass refers to any of various alloys consisting essentially of copper and zinc, used for windows, railings, trim, and finish hardware.  Alloys that are brass by definition may have names that include the word bronze, as architectural bronze. 

Lead is a heavy, soft, malleable, bluish-gray metallic element used for flashing, sound isolation, and radiation shielding.  Although lead is the heaviest of the common metals, its pliability makes it desirable for application over uneven surfaces.  Lead dust and vapors are toxic. 

### **Galvanic Action**

Galvanic action can occur between two dissimilar metals when enough moisture is present for electric current to flow.  This electric current will tend to corrode one metal while plating the other.  The severity of the galvanic action depends on how far apart the two metals are on the galvanic series table. 

  * Gold, platinum
  * Titanium
  * Silver
  * Stainless steel
  * Bronze
  * Copper
  * Brass
  * Nickel
  * Tin
  * Lead
  * Cast iron
  * Mild steel
  * Aluminum, 2024 T4
  * Cadmium
  * Aluminum, 1100
  * Zinc
  * Magnesium

### **Galvanic Series**

  * The galvanic series lists metals in order from most noble to least noble. 
  * Noble metals, such as gold and silver, resist oxidation when heated in air and solution by inorganic acids. 
  * The metal that is lower in the list is sacrificial and corrodes when enough moisture is present for electric current to flow. 
  * The farther apart two metals are on the list, the more susceptible the least noble one is to corrosive deterioration. 

**CSI MasterFormat Division 05: Metals**

## **12.10 STONE**

Stone is an aggregate or combination of minerals, each of which is composed of inorganic chemical substances.  To qualify as a construction material, stone should have the following qualities:

  * Strength: Most types of stone have more than adequate compressive strength.  The shear strength of stone, however, is usually about 1/10 of its compressive strength. 
  * Hardness: Hardness is important when stone is used for flooring, paving, and stair treads. 
  * Durability: Resistance to the weathering effects of rain, wind, heat, and frost action is necessary for exterior stonework. 
  * Workability: A stone's hardness and grain texture must allow it to be quarried, cut, and shaped. 
  * Density: A stone's porosity affects its ability to withstand frost action and staining. 
  * Appearance: Appearance factors include color, grain, and texture. 

Stone may be classified according to geological origin into the following types:

As a loadbearing wall material, stone is similar to modular unit masonry.  Although stone masonry is not necessarily uniform in size, it is laid up with mortar and used in compression.  Almost all stone is adversely affected by sudden changes in temperature and should not be used where a high degree of fire resistance is required. 

Stone is used in construction in the following forms:

  * Rubble consists of rough fragments of broken stone that have at least one good face for exposure in a wall. 
  * Dimension stone is quarried and squared stone 2′ (610) or more in length and width and of specified thickness, used commonly for wall panels, cornices, copings, lintels, and flooring. 
  * Flagstone refers to flat stone slabs used for flooring and horizontal surfacing. 
  * Crushed stone is used as aggregate in concrete products. 

  * See 5.33 for types of stone masonry. 

**CSI MasterFormat 04 40 00: Stone Assemblies**

## **12.11 WOOD**

As a construction material, wood is strong, durable, light in weight, and easy to work.  In addition, it offers natural beauty and warmth to sight and touch.  Although it has become necessary to employ conservation measures to ensure a continued supply, wood is still used on construction in many and varied forms. 

There are two major classes of wood—softwood and hardwood.  These terms are not descriptive of the actual hardness, softness, or strength of a wood.  Softwood is the wood from any of various predominantly evergreen, cone-bearing trees, such as pine, fir, hemlock, and spruce, used for general construction.  Hardwood is the wood from a broad-leaved flowering tree, such as cherry, maple, or oak, typically used for flooring, paneling, furniture, and interior trim. 

The manner in which a tree grows affects its strength, its susceptibility to expansion and contraction, and its effectiveness as an insulator.  Tree growth also affects how pieces of sawn wood may be joined to form the structure and enclosure of a building. 

Grain direction is the major determining factor in the use of wood as a structural material.  Tensile and compressive forces are best handled by wood in a direction parallel to the grain.  Typically, a given piece of wood will withstand 1/3 more force in compression than in tension parallel to its grain.  The allowable compressive force perpendicular to its grain is only about 1/5 to ½ of the allowable compressive force parallel to the grain.  Tensile forces perpendicular to the grain will cause the wood to split.  The shear strength of wood is greater across its grain than parallel to the grain.  It is therefore more susceptible to horizontal shear than to vertical shear. 

The manner in which lumber is cut from a log affects its strength as well as its appearance.  Plainsawing a squared log into boards with evenly spaced parallel cuts results in flat grain lumber that:

  * May have a variety of noticeable grain patterns;
  * Tends to twist and cup, and wears unevenly;
  * Tends to have raised grain;
  * Shrinks and swells less in thickness, more in width. 

Quartersawing logs approximately at right angles to the annual rings results in edge or vertical grain lumber that:

  * Has more even grain patterns;
  * Wears more evenly with less raised grain and warping;
  * Shrinks and swells less in width, more in thickness;
  * Is less affected by surface checks;
  * Results in more waste in cutting and is more expensive. 

**CSI MasterFormat Division 06: Wood, Plastics, and Composites**

## **12.12 WOOD**

To increase its strength, stability, and resistance to fungi, decay, and insects, wood is seasoned—dried to reduce its moisture content—by air-drying or kiln-drying under controlled conditions of heat, air circulation, and humidity.  It is impossible to completely seal a piece of wood to prevent changes in its moisture content.  Below a moisture content of about 30%, wood expands as it absorbs moisture and shrinks as it loses moisture.  This possibility of shrinkage and swelling must always be taken into account when detailing and constructing wood joints, both in small- and large-scale work. 

Shrinkage tangential to the wood grain is usually twice as much as radial shrinkage.  Vertical grain lumber shrinks uniformly while plainsawn cuts near a log's perimeter will cup away from the center.  Because the thermal expansion of wood is generally much less than volume changes due to changes in moisture content, moisture content is therefore the controlling factor. 

Wood is decay-resistant when its moisture content is under 20%.  If installed and maintained below this moisture content level, wood will usually not rot.  Species that are naturally resistant to decay-causing fungi include redwood, cedar, bald cypress, black locust, and black walnut.  Insect-resistant species include redwood, eastern red cedar, and bald cypress. 

Preservative treatments are available to further protect wood from decay and insect attack.  Of these, pressure treatment is the most effective, especially when the wood is in contact with the ground.  There are three types of preservatives. 

  * Water-borne preservatives leave the wood clean, odorless, and readily paintable; preservatives do not leach out when exposed to weather.  
    * AWPB (American Wood Preservers Bureau)
    * LP-2 (LP-22 for ground contact)
  * Oil-borne preservatives may color the wood, but treated wood is paintable; pentachlorophenol is highly toxic.  
    * AWPB LP-3 (LP-33 for ground contact)
  * Creosote treatment leaves wood with colored, oily surfaces; odor remains for a long period; used especially in marine and saltwater installations.  
    * AWPB LP-5 (LP-55 for ground contact)

Defects affect the grading, appearance, and use of wood members.  They may also affect a wood's strength, depending on their number, size, and location.  Defects include the natural characteristics of wood, such as knots, shakes, and pitch pockets, as well as the effects of manufacturing, such as checks and warping. 

## **12.13 LUMBER**

Because of the diversity of its applications and its use for remanufacturing purposes, hardwood is graded according to the amount of clear, usable lumber in a piece that may be cut into smaller pieces of a certain grade and size.  Softwood is classified in the following manner. 

  * Factory and shop lumber: sawn or selected primarily for further manufacture into doors, windows, and millwork, and graded according to the amount of usable wood that will produce cuttings of a specified size and quality

Lumber is specified by species and grade.  Each piece of lumber is graded for structural strength and appearance.  Structural lumber may be graded visually by trained inspectors according to quality-reducing characteristics that affect strength, appearance, or utility, or by a machine that flexes a test specimen, measures its resistance to bending, calculates its modulus of elasticity, and electronically computes the appropriate stress grade, taking into account such factors as the effects of knots, slope of grain, density, and moisture content. 

  * Lumber is measured in board feet; 1 board foot is equal to the volume of a piece whose nominal dimensions are 12″ (305) square and 1″ (25) thick. 

  * For dressed sizes: 
    * Subtract ¼″ (6) from nominal dimensions up to 2″ (51);
    * Subtract ½″ (13) from nominal dimensions of 2″ to 6″ (51 to 150);
    * Subtract ¾″ (19) from nominal dimensions greater than 6″ (150). 
  * Lumber is generally available in lengths from 6′ to 24′ (1830 to 7315), in multiples of 2′ (610). 

## **12.14 WOOD PANEL PRODUCTS**

Wood panel products are less susceptible to shrinking or swelling, require less labor to install, and make more efficient use of wood resources than solid wood products.  The following are the major types of wood panel products. 

## **12.15 PLASTICS**

Plastics are any of the numerous synthetic or natural organic materials that are mostly thermoplastic or thermosetting polymers of high molecular weight and that can be molded, extruded, or drawn into objects, films, or filaments.  As a class, plastics are tough, resilient, lightweight, and resistant to corrosion and moisture.  Many plastics also emit gases harmful to the respiratory system and release toxic fumes when burned. 

While there are many types of plastics with a wide range of characteristics, they can be divided into two basic categories:

  * Thermosetting plastics go through a pliable stage, but once they are set or cured, they become permanently rigid and cannot be softened again by reheating. 
  * Thermoplastics are capable of softening or fusing when heated without a change in any inherent properties, and of hardening again when cooled. 

In the table below are listed the plastics that are commonly used in construction and their primary uses. 

**CSI MasterFormat 06 50 00: Structural Plastics  
CSI MasterFormat 06 60 00: Plastic Fabrications**

## **12.16 GLASS**

Glass is a hard, brittle, chemically inert substance produced by fusing silica together with a flux and a stabilizer into a mass that cools to a rigid condition without crystallization.  It is used in building construction in various forms.  Foamed or cellular glass is used as rigid, vaporproof thermal insulation.  Glass fibers are used in textiles and for material reinforcement.  In spun form, glass fibers form glass wool, which is used for acoustical and thermal insulation.  Glass block is used to control light transmission, glare, and solar radiation.  Glass, however, is used most commonly to glaze the window, sash, and skylight openings of buildings. 

The three major types of flat glass are the following:

  * Sheet glass is fabricated by drawing the molten glass from a furnace (drawn glass), or by forming a cylinder, dividing it lengthwise, and flattening it (cylinder glass).  The fire-polished surfaces are not perfectly parallel, resulting in some distortion of vision.  To minimize this distortion, glass should be glazed with the wave distortion running horizontally. 
  * Plate glass is formed by rolling molten glass into a plate that is subsequently ground and polished after cooling.  Plate glass provides virtually clear, undistorted vision. 
  * Float glass is manufactured by pouring molten glass onto a surface of molten tin and allowing it to cool slowly.  The resulting flat, parallel surfaces minimize distortion and eliminate the need for grinding and polishing.  Float glass is the successor to plate glass and accounts for the majority of flat-glass production. 

Other types of glass include the following:

  * Annealed glass is cooled slowly to relieve internal stresses. 
  * Heat-strengthened glass is annealed glass that is partially tempered by a process of reheating and sudden cooling.  Heat-strengthened glass has about twice the strength of annealed glass of the same thickness. 
  * Tempered glass is annealed glass that is reheated to just below the softening point and then rapidly cooled to induce compressive stresses in the surfaces and edges of the glass and tensile stresses in the interior.  Tempered glass has three to five times the resistance of annealed glass to impact and thermal stresses but cannot be altered after fabrication.  When fractured, it breaks into relatively harmless pebble-sized particles. 
  * Laminated or safety glass consists of two or more plies of flat glass bonded under heat and pressure to interlayers of polyvinyl butyral resin that retains the fragments if the glass is broken.  Security glass is laminated glass that has exceptional tensile and impact strength. 
  * Wired glass is flat or patterned glass having a square or diamond wire mesh embedded within it to prevent shattering in the event of breakage or excessive heat.  Wired glass is considered a safety glazing material and may be used to glaze fire doors and windows. 
  * Patterned glass has a linear or geometric surface pattern formed in the rolling process to obscure vision or to diffuse light. 
  * Obscure glass has one or both sides acid-etched or sand-blasted to obscure vision.  Either process weakens the glass and makes it difficult to clean. 
  * Spandrel glass is an opaque glass for concealing the structural elements in curtain wall construction, produced by fusing a ceramic frit to the interior surface of tempered or heat-strengthened glass. 

  * Insulating glass is a glass unit consisting of two or more sheets of glass separated by a hermetically sealed air space to provide thermal insulation and restrict condensation; glass edge units have a 3/16″ (5) air space; metal edge units have a ¼″ or ½″ (6 or 13) air space. 

  * Tinted or heat-absorbing glass has a chemical admixture to absorb a portion of the radiant heat and visible light that strike it.  Iron oxide gives the glass a pale blue-green tint; cobalt oxide and nickel impart a grayish tint; selenium infuses a bronze tint. 

  * Reflective glass has a thin, translucent metallic coating to reflect a portion of the light and radiant heat that strike it.  The coating may be applied to one surface of single glazing, in between the plies of laminated glass, or to the exterior or interior surfaces of insulating glass. 

  * Low-emissivity (low-e) glass transmits visible light while selectively reflecting the longer wavelengths of radiant heat, produced by depositing a low-e coating either on the glass itself or over a transparent plastic film suspended in the sealed air space of insulating glass. 

**CSI MasterFormat 08 81 00: Glass Glazing**

## **12.17 GLASS PRODUCTS**

## **12.18 NAILS**

Nails are straight, slender pieces of metal having one end pointed and the other enlarged and flattened for hammering into wood or other building materials as a fastener. 

### **Material**

  * Nails are usually of mild steel, but may also be of aluminum, copper, brass, zinc, or stainless steel. 
  * Tempered, high-carbon steel nails are used for greater strength in masonry applications. 
  * The type of metal used should be compatible with the materials being secured to avoid loss of holding power and prevent staining of the materials. 

### **Length and Diameter of the Shank**

  * Nail lengths are designated by the term penny (d). 
  * Nails range in length from 2d, about 1″ (25) long, to 60d, about 6″ (150) long. 
  * Nail length should be about 3 x thickness of the material being secured. 
  * Large diameter nails are used for heavy work while lighter nails are used for finish work; thinner nails are used for hardwood rather than for softwood. 

### **Form of the Shank**

  * For greater gripping strength, nail shafts may be serrated, barbed, threaded, fluted, or twisted. 
  * Nail shafts may be cement-coated for greater resistance to withdrawal, or be zinc-coated for corrosion resistance. 

  * Common nails
  * For general construction (2d to 60d)

  * Box nails
  * For light construction (2d to 40d)

  * Casing nails
  * For finish work (2d to 40d)

  * Finishing nails
  * For cabinetry (2d to 20d)

  * Flooring nails
  * For fastening floor boards

  * Cut nails
  * For wood flooring

  * Roofing nails
  * For fastening shingles

  * Double-headed nails
  * For temporary structures

  * Masonry nails
  * For hammering into concrete or masonry

  * Spikes
  * For fastening heavy timbers

  * Power-driven studs
  * For driving into concrete or steel

### **Nail Heads**

  * Flat heads provide the largest amount of contact area and are used when exposure of the heads is acceptable. 
  * The heads of finish nails are only slightly larger than the shaft and may be tapered or cupped. 
  * Double-headed nails are used for easy removal in temporary construction and concrete formwork. 

### **Nail Points**

  * Most nails have diamond-shaped points. 
  * Sharp-pointed nails have greater holding strength but may tend to split some woods; blunt points should be used for easily split woods. 

### **Power-Driven Fasteners**

  * Pneumatic nailers and staplers, driven by a compressor, are capable of fastening materials to wood, steel, or concrete. 
  * Powder-driven fasteners use gunpowder charges to drive a variety of studs into concrete or steel. 

**CSI MasterFormat 06 06 00: Schedules for Wood, Plastics, and Composites**

## **12.19 SCREWS & BOLTS**

### **Screws**

Screws are metal fasteners having tapered, helically threaded shanks and slotted heads, designed to be driven into wood or the like by turning, as with a screwdriver.  Because of their threaded shafts, screws have greater holding power than nails, and are more easily removable.  The more threads they have per inch, the greater their gripping strength.  Screws are classified by use, type of head, material, length, and diameter. 

  * Material: steel, brass, aluminum, bronze, stainless steel
  * Lengths: ½″ to 6″ (13 to 150)
  * Diameters: up to 24 gauge

  * Flat head

  * Oval head

  * Round head

  * Truss head

  * Pan head

  * Fillister head

  * Bugle head

  * Security head

  * Wood screw

  * Drywall screw

  * Machine screw

  * Self-tapping screw

  * Sheet metal screw

  * Cap screw

  * Set screw

  * Slotted head

  * Phillips head

  * Allen head

  * Square drive

The length of a wood screw should be about ⅛″ (3) less than the combined thickness of the boards being joined, with ½ to ⅔ of the screw's length penetrating the base material.  Fine-threaded screws are generally used for hardwoods while coarse-threaded ones are used for softwoods. 

Holes for screws should be predrilled and be equal to the base diameter of the threads.  Some screws, such as self-tapping and drywall screws, are designed to tap corresponding female threads as they are driven. 

### **Bolts**

Bolts are threaded metal pins or rods, usually having a head at one end, designed to be inserted through holes in assembled parts and secured by a mating nut.  Carriage bolts are used where the head may be inaccessible during tightening.  Lag bolts or screws are used in areas inaccessible to the placement of a nut or where an exceptionally long bolt would be needed to penetrate a joint fully. 

  * Lengths: ¾″ to 30″ (75 to 760)
  * Diameters: ¼″ to 1-¼″ (6 to 32)

  * Lock nut

  * Castellated nut

  * Cap nut

  * Machine bolt

  * Hexagonal head
  * Square head

  * Carriage bolt
  * Square neck

  * Washers are perforated disks of metal, rubber, or plastic, used under the head of a nut or bolt or at a joint to distribute pressure, prevent leakage, relieve friction, or insulate incompatible materials. 
  * Lock washers are specially constructed to prevent a nut from shaking loose. 

  * Spring-lock washer

  * External-tooth lock washer

  * Lag bolt or screw

  * Load-indicating washers have small projections that are progressively flattened as a bolt is tightened, the gap between the head or nut and the washer indicating the tension in the bolt. 

## **12.20 MISCELLANEOUS FASTENINGS**

  * Expansion bolts are anchor bolts having a split casing that expands mechanically to engage the sides of a hole drilled in masonry or concrete. 

### **Adhesives**

Adhesives are used to secure the surfaces of two materials together.  Numerous types of adhesives are available, many of them being tailor-made for use with specific materials and under specified conditions.  They may be supplied in the form of a solid, liquid, powder, or film; some require a catalyst to activate their adhesive properties.  Always follow the manufacturer's recommendations in the use of an adhesive.  Important considerations in the selection of an adhesive include:

  * Strength: Adhesives are usually strongest in resisting tensile and shear stresses and weakest in resisting cleavage or splitting stresses. 
  * Curing or setting time: This ranges from immediate bonding to curing times of up to several days. 
  * Setting temperature range: Some adhesives will set at room temperature while others require baking at elevated temperatures. 
  * Method of bonding: Some adhesives bond on contact while others require clamping or higher pressures. 
  * Characteristics: Adhesives vary in their resistance to water, heat, sunlight, and chemicals, as well as their aging properties. 

Common types of adhesives:

  * Animal or fish glues are primarily for indoor use where temperature and humidity do not vary greatly; they may be weakened by exposure to heat or moisture. 
  * White or polyvinyl glue sets quickly, does not stain, and is slightly resilient. 
  * Epoxy resins are extremely strong and may be used to secure both porous and nonporous materials; they may dissolve some plastics.  Unlike other adhesives, epoxy glues will set at low temperatures and under wet conditions. 
  * Resorcin resins are strong, waterproof, and durable for outdoor use, but they are flammable and their dark color may show through paint. 
  * Contact cement forms a bond on contact and therefore does not require clamping.  It is generally used to secure large sheet materials such as plastic laminate. 

## **12.21 PAINTS & COATINGS**

The purpose of a coating is to protect, preserve, or visually enhance the surface to which it is applied.  The principal types of coating are paints, stains, and varnishes. 

  * Primers are basecoats applied to a surface to improve the adhesion of subsequent coats of paint or varnish. 
  * Sealers are basecoats applied to a surface to reduce the absorption of subsequent coats of paint or varnish, or to prevent bleeding through the finish coat. 

  * Oil paints use a drying oil that oxidizes and hardens to form a tough elastic film when exposed in a thin layer to air. 
  * Alkyd paints have as a binder an alkyd resin, such as a chemically modified soy or linseed oil. 
  * Latex paints have as a binder an acrylic resin that coalesces as water evaporates from the emulsion. 

  * Epoxy paints have an epoxy resin as a binder for increased resistance to abrasion, corrosion, and chemicals. 
  * Rust-inhibiting paints and primers are specially formulated with anticorrosive pigments to prevent or reduce the corrosion of metal surfaces. 
  * Fire-retardant paints are specially formulated with silicone, polyvinyl chloride, or other substance to reduce the flame-spread of a combustible material. 
  * Intumescent coatings, when exposed to the heat of a fire, swell to form a thick insulating layer of inert foam that retards flame spread and combustion. 
  * Heat-resistant paints are specially formulated with silicone resins to withstand high temperatures. 

### **Varnishes**

Varnish is a liquid preparation consisting of a resin dissolved in an oil (oil varnish) or in alcohol (spirit varnish), that when spread and allowed to dry forms a hard, lustrous, usually transparent coating. 

  * Spar or marine varnish is a durable, weather-resistant varnish made from durable resins and linseed or tung oil. 
  * Polyurethane varnish is an exceptionally hard, abrasion-resistant, and chemical-resistant varnish made from a plastic resin of the same name. 
  * Lacquer refers to any of various clear or colored synthetic coatings consisting of nitrocellulose or other cellulose derivative dissolved in a solvent that dries by evaporation to form a high-gloss film. 
  * Shellac is a spirit varnish made by dissolving purified lac flakes in denatured alcohol. 

### **Stains**

Stain is a solution of dye or suspension of pigment in a vehicle, applied to penetrate and color a wood surface without obscuring the grain. 

  * Penetrating stains permeate a wood surface, leaving a very thin film on the surface. 
  * Water stain is a penetrating stain made by dissolving dye in a water vehicle. 
  * Spirit stain is a penetrating stain made by dissolving dye in an alcohol or spirit vehicle. 

  * Pigmented or opaque stain is an oil stain containing pigments capable of obscuring the grain and texture of a wood surface. 
  * Oil stain is made by dissolving dye or suspending pigment in a drying oil or oil varnish vehicle. 

**CSI MasterFormat 09 90 00: Painting and Coating**

## **12.22 PAINTS & COATINGS**

All materials to receive paint or other coating must be properly prepared and primed to ensure adhesion of the coating to their surfaces and to maximize the life of the coating.  In general, surfaces should be dry and free of contaminants, such as dirt, grease, moisture, and mildew.  The following are recommendations for various materials:

  * Brick surface should have dirt, loose mortar, efflorescence, and other foreign matter removed by wire brushing, air pressure, or steam cleaning.  Seal with a latex primer-sealer or a clear silicone water-repellant. 

  * Concrete masonry should be thoroughly dry and free of dirt and loose or excess mortar.  Porous surfaces may require a block filler or cement grout primer if the acoustical value of a rough surface is not important. 

  * Concrete surface should be well-cured and free of dirt, form oils, and curing compounds.  Porous surfaces may require a block filler or cement grout primer.  Prime grouted surfaces with a latex, alkyd, or oil primer-sealer.  Concrete surfaces may also be sealed with a clear silicone water-repellant. 

  * Concrete floors should be free of dirt, wax, grease, and oils, and should be etched with a muriatic acid solution to improve adhesion of the coating.  Prime with an alkali-resistant coating. 

  * Gypsum board surfaces should be clean and dry.  Use a latex primer-sealer to avoid raising the fibers of the paper surface. 

  * Plaster and stucco surfaces should be allowed to dry thoroughly and be completely cured.  Prime with a latex, alkyd, or oil primer-sealer.  Fresh plaster should be primed with an alkali-resistant coating. 

  * Wood should be clean, dry, well-seasoned lumber.  Knots and pitch stains should be sanded and sealed before priming.  Surfaces to be painted should be primed or sealed to stabilize the moisture content of the wood and prevent the absorption of succeeding coats; stains and some paints may be self-priming.  All nail holes, cracks, and other small holes should be filled after the prime coat. 

  * Old paint surfaces should be clean, dry, and roughened by sanding or washing with a detergent solution. 
  * Ferrous metal surfaces should be free of rust, metal burrs, and foreign matter.  Clean with solvents or by wire brushing, sandblasting, flame cleaning, or pickling with acids.  Prime with a rust-inhibitive primer. 

  * Galvanized iron should have all grease, residue, and corrosion removed with a solvent or chemical wash.  Prime with a zinc oxide or portland cement paint.  If weathered, galvanized iron should be treated as a ferrous metal. 

In addition to the surface preparation and priming required, other considerations in the selection of a coating include:

  * Compatibility of the coating with the surface to which it is applied
  * The method of application and drying time required
  * Conditions of use and the required resistance to water, heat, sunlight, temperature variation, mildew, chemicals, and physical abrasion
  * The possible emission of harmful volatile organic compounds

# **A  
Appendix**

A.02 Human dimensions

A.03 ADA Accessibility Guidelines

A.04 Furniture Dimensions

A.06 Building Live Loads

A.07 Weights of Materials

A.08 Metric Conversion Factors

A.10 Means of Egress

A.12 Fire-Rated Construction

A.14 Acoustics

A.16 Sound Control

A.18 Graphic Material Symbols

A.19 CSI MasterFormat

A.23 Uniformat II

A.26 LEED Green Building Rating System

A.27 Professional & Trade Associations

## **A.02 HUMAN DIMENSIONS**

Our body dimensions, and the way we move through and perceive space, are prime determinants of the scale, proportions, and spatial layout of a building.  It should be noted that there is a difference between the structural dimensions of our bodies and those dimensional requirements that result from how we reach for something on a shelf, sit down at a table, walk down a stairway, or interact with other people.  These functional dimensions will vary according to the nature of our activity and the social situation. 

Caution should always be exercised when using a set of dimensional tables or illustrations such as these.  These are based on average measurements, which may have to be adjusted to satisfy specific user needs.  Variations from the norm will always exist due to the differences between men and women, among various age and racial groups, and from one individual to the next. 

## **A.03 ADA ACCESSIBILITY GUIDELINES**

The Americans with Disabilities Act (ADA) of 1990 is federal civil-rights legislation requiring that buildings be accessible to persons with physical disabilities and certain defined mental disabilities.  The ADA Accessibility Guidelines (2010 ADA Standards for Accessible Design) are maintained by the U.S. Access Board, an independent federal agency, and the regulations are administered by the U.S. Department of Justice.  Federal facilities must comply with standards issued under the Architectural Barriers Act (ABA).  In its last update, the Access Board harmonized the ADA guidelines with its guidelines for facilities covered by the ABA and published them jointly as the ADA-ABA Accessibility Guidelines.  Related legislation includes the Federal Fair Housing Act (FFHA) of 1988, which contains Department of Housing and Urban Development (HUD) regulations requiring residential complexes of four or more dwelling units to be adaptable for use by persons with disabilities. 

Facilities should be accessible to those confined to a wheelchair and the ambulatory. 

  * Accessible routes consist of walking surfaces with a maximum slope of 1:20, marked crossings at vehicular roadways, clear floor space at accessible elements, access aisles, ramps, curb ramps, and elevators. 
  * Floor surfaces should be firm, stable, and slip-resistant. 
  * Avoid changes in level and the use of stairs. 
  * Use ramps only where necessary. 

Facilities should be identifiable to the blind. 

  * Use raised lettering, audible warning signals, and textured surfaces to indicate stairs or hazardous openings. 

Facilities should be usable. 

  * Circulations spaces should be adequate for comfortable movement. 
  * All public facilities should have fixtures designed for use by persons with disabilities. 

For ADA Accessibility Guidelines for other building elements or components, see the following:

  * Vehicular parking: 1.29
  * Doors: 8.03
  * Door hardware: 8.17, 8.19, 8.20
  * Thresholds: 8.21
  * Windows: 8.22
  * Stairs and ramps: 9.05, 9.09
  * Elevators: 9.16
  * Kitchens: 9.22–9.23
  * Toilet and bathing facilities: 9.26
  * Carpeting: 10.21

## **A.04 FURNITURE DIMENSIONS**

### **Armchairs**

### **Beds**

### **Side Chairs**

### **Night Tables**

### **High Chests**

### **Lounge Chairs**

### **Low Tables**

### **Sofas**

### **Stools**

### **Benches**

## **A.05 FURNITURE DIMENSIONS**

### **Dining Tables**

### **Desks**

### **Swivel Chairs**

### **Conference Tables**

### **Credenzas**

### **File Cabinets**

  * All dimensions are typical.  Verify with furniture manufacturer. 
  * Furniture may serve as space-defining elements, define circulation paths, or be built-in or set as objects in space. 
  * Selection factors include function, comfort, scale, color, and style. 

## **A.06 BUILDING LIVE LOADS**

### **Minimum Uniformly Distributed Loads (psf*)**

***1 psf = 47.88 Pa**

**Assembly Facilities**

• Theaters with fixed seating | 60  
---|---  
• Auditoriums and gyms w/ movable seats  | 100  
• Corridors and lobbies | 100  
• Stages | 150

**Libraries**

• Reading rooms | 60  
---|---  
• Book stacks | 150

**Offices**

• Office spaces | 80  
---|---  
• Lobbies | 100

**Residential Facilities**

• Private dwellings | 40  
---|---  
• Apartment units, hotel rooms | 40  
• Public rooms | 100  
• Corridors | 60

**Schools**

• Classrooms | 40  
---|---  
• Corridors | 100

**Sidewalks and Vehicular Drives** 250

**Stairs, Fire Escapes, Exitways** 100

**Storage Warehouses**

• Light | 125  
---|---  
• Heavy | 250

**Manufacturing Facilities** 125

**Stores**

• Retail: first floor | 100  
---|---  
• Upper floors | 75

**Roof Loads**

• Minimum, not including wind or seismic loads | 20  
---|---  
• Roof gardens | 100

  * In the design of a building, the assumed live loads should be the maximum expected to be produced by the intended use or activity.  In some instances, such as with parking garages, concentrated loads will take precedence. 
  * Always verify live load requirements with the building code. 

### **Average Weights of Materials (pcf*)**

***1 pcf = 16 kg/m 3**

**Soil, Sand and Gravel**

• Cinder | 45  
---|---  
• Clay, damp | 110  
• Clay, dry | 63  
• Earth, dry and loose | 76  
• Earth, moist and packed | 96  
• Sand and gravel, dry and loose | 105  
• Sand and gravel, wet | 120

**Wood**

• Cedar | 22  
---|---  
• Douglas fir | 32  
• Hemlock | 29  
• Maple | 42  
• Oak, red | 41  
• Oak, white | 46  
• Pine, southern | 29  
• Redwood | 26  
• Spruce | 27

**Metals**

• Aluminum | 165  
---|---  
• Brass, red | 546  
• Bronze, statuary | 509  
• Copper | 556  
• Iron, cast | 450  
• Iron, wrought | 485  
• Lead | 710  
• Nickel | 565  
• Stainless steel | 510  
• Steel, rolled | 490  
• Tin | 459  
• Zinc | 440

**Concrete**

• Stone, plain | 144  
---|---  
• Stone, reinforced | 150  
• Cinder | 100  
• Lightweight, expanded shale | 105  
• Lightweight, perlite | 35–50

**Stone**

• Granite | 175  
---|---  
• Limestone | 165  
• Marble | 165  
• Sandstone | 147  
• Slate | 175

**Water**

• Maximum density @ 4°C | 62  
---|---  
• Ice | 56  
• Snow | 8

## **A.07 WEIGHTS OF MATERIALS**

### **Average Weights of Materials (psf*)**

***1 psf = 47.88 Pa**

**Walls and Partitions**

• Brick, per 4″ (100) of thickness | 35  
---|---  
• Concrete masonry units |   
w/ stone or gravel aggregate |   
4″ (100) | 34  
6″ (150) | 50  
8″ (205) | 58  
12″ (305) | 90  
w/ lightweight aggregate |   
4″ (100) | 22  
6″ (150) | 31  
8″ (205) | 38  
12″ (305) | 55  
• Glass block, 4″ (100) | 18  
• Gypsum board, ½″ (51) | 2  
• Metal lath | 0.5  
• Metal studs with gypsum board | 6  
• Plaster, 1″ (25)  
Cement plaster | 10  
Gypsum plaster | 5  
• Plywood, ½″ (13) | 1.5  
• Stone |   
Granite, 4″ (100) | 59  
Limestone, 6″ (150) | 55  
Marble, 1″ (25) | 13  
Sandstone, 4″ (100) | 49  
Slate, 1″ (25) | 14  
• Tile, ceramic | 2.5  
Glazed wall tile | 3  
• Tile, structural clay |   
4″ (100) | 18  
6″ (150) | 28  
8″ (205) | 34  
• Wood studs, 2x4, with |   
gypsum board on both sides | 8

**Insulation**

• Batt or blanket, per inch | 0.3  
---|---  
• Fiberboard | 2  
• Foamed board, per inch | 0.2  
• Loose | 0.5  
• Poured in place | 2  
• Rigid | 0.8

**Glass**

• See 12.17 |   
---|---

### **Average Weights of Materials (psf*)**

***1 psf = 47.88 Pa**

**Floor and Roof Construction**

• Concrete, reinforced, per inch (25) |   
---|---  
Stone | 12.5  
Perlite | 6–10  
Concrete, plain, per inch  
Stone | 12  
Lightweight | 3–9  
• Concrete, precast |   
6″ (150) hollow core, stone | 40  
6″ (150) hollow core, lightweight | 30  
2″ (51) cinder concrete plank | 15  
2″ (51) gypsum plank | 12  
• Steel deck | 2–4

**Roofing**

• Built-up, 5-ply felt and gravel | 6  
---|---  
• Copper or tin | 2  
• Corrugated iron | 2  
• Corrugated fiberglass | 0.5  
• Monel metal | 1.5  
• Shingles |   
Composition | 3  
Slate | 10  
Wood | 2  
• Tile |   
Concrete | 16  
Clay | 14

**Ceilings**

• Acoustical tile, ¾″ (19) | 1  
---|---  
• Acoustic plaster on gypsum lath | 10  
• Channel suspended system | 1

**Floor Finishes**

• Cement finish, 1″ (25) | 12  
---|---  
• Marble | 30  
• Terrazzo, 1″ (25) | 13  
• Wood |   
Hardwood 25/32″ (20) | 4  
Softwood ¾″ (19) | 4.5  
Wood block 3″ (75) | 15  
• Vinyl tile | 1.33

## **A.08 METRIC CONVERSION FACTORS**

The International System of Units (SI), more commonly known as the metric system, is an internationally accepted system of coherent physical units, using the meter, gram, second, ampere, kelvin, and candela as the basic units of the fundamental quantities of length, mass, time, electric current, temperature, and luminous intensity.  The metric system is universally used in science and mandatory for use in a large number of countries. 

## **A.09 METRIC CONVERSION FACTORS**

## **A.10 MEANS OF EGRESS**

Building codes specify:

  * The fire-resistance ratings of materials and construction required for a building, depending on its location, use and occupancy, and size (height and area per floor); see 2.06–2.07. 
  * The fire alarm, sprinkler, and other protection systems required for certain uses and occupancies; see 11.25. 
  * The required means of egress for the occupants of a building in case of a fire.  A means of egress must provide safe and adequate access from any point in a building to protected exits leading to a place of refuge.  There are three components to an egress system: exit access, exits, and exit discharge. 

  * Occupant load is the total number of persons that may occupy a building or portion thereof at any one time, determined by dividing the floor area assigned to a particular use by the square feet per occupant permitted in that use.  Building codes use occupant load to establish the required number and width of exits for a building. 

These requirements are intended to control the spread of fire and to allow sufficient time for the occupants of a burning building to exit safely before the structure weakens to the extent that it becomes dangerous.  Consult the building code for specific requirements. 

### **Exit Access**

The path or passageway leading to an exit should be as direct as possible, be unobstructed by projections such as open doors, and be well lit. 

## **A.11 MEANS OF EGRESS**

### **Exits**

An exit must provide an enclosed and protected means of evacuation for the occupants of a building in the event of fire, leading from an exit access to an exit discharge.  From a ground floor room or corridor, it may simply be a door opening directly to the outside.  From a room or space above or below grade, a required exit usually consists of an exit stairway. 

## **A.12 FIRE-RATED CONSTRUCTION**

Fire-rated materials, assemblies, and construction have a fire-resistance rating required by their uses.  This fire-resistance rating is determined by subjecting a full-size specimen to temperatures according to a standard time-temperature curve and establishing the length of time in hours the material or assembly can be expected to withstand exposure to fire without collapsing, developing any openings that permit the passage of flame or hot gases, or exceeding a specified temperature on the side away from the fire.  Fire-resistant construction therefore involves both reducing the flammability of a material and controlling the spread of fire. 

### **Heavy Timber (Type IV) Construction**

  * See 2.06. 

Materials used to provide fire protection must be inflammable and be able to withstand very high temperatures without disintegrating.  They should also be low conductors of heat to insulate the protected materials from the heat generated by a fire.  Such materials include concrete, often with lightweight aggregate, gypsum or vermiculite plaster, gypsum wallboard, and a variety of mineral fiber products. 

On this and the facing page is a sampling of fire-resistance ratings for various construction assemblies.  For more detailed specifications, consult the Underwriters' Laboratories, Inc. Materials List, or the governing building code.  See also 2.06 for a table of the fire-resistance rating requirements for major building components. 

### **Structural Steel**

  * Because structural steel can be weakened by the high temperatures of a fire, it requires protection to qualify for certain types of construction. 

## **A.13 FIRE-RATED CONSTRUCTION**

### **Floors and Roofs**

**1-Hour Rating**

**2-Hour Rating**

**1-Hour Rating**

**4-Hour Rating**

### **Walls and Partitions**

**1-Hour Rating**

**2-Hour Rating**

**CSI MasterFormat 07 80 00: Fire and Smoke Protection**

## **A.14 ACOUSTICS**

Acoustics is the branch of physics that deals with the production, control, transmission, reception, and effects of sound.  Sound may be defined as the sensation stimulated in the organs of hearing by mechanical radiant energy transmitted as longitudinal pressure waves through the air or other medium. 

  * Sound waves are longitudinal pressure waves in air or an elastic medium producing an audible sensation. 
  * Sound travels through air at approximately 1087′ (0.3 km) per second at sea level, through water at approximately 4500′ (1.4 km) per second, through wood at approximately 11,700′ (3.6 km) per second, and through steel at approximately 18,000′ (5.5 km) per second. 

  * Equal loudness contour is a curve representing the sound pressure level at which sounds of different frequencies are judged by a group of listeners to be equally loud. 

## **A.15 ACOUSTICS**

Acoustical design is the planning, shaping, finishing, and furnishing of an enclosed space to establish the acoustical environment necessary for distinct hearing of speech or musical sounds. 

  * Attenuation is a decrease in energy or pressure per unit area of a sound wave, occurring as the distance from the source increases as a result of absorption, scattering, or spreading in three dimensions. 

  * Reverberation is the persistence of a sound within an enclosed space, caused by multiple reflection of the sound after its source has stopped.  Reverberation time is the time in seconds required for a sound made in an enclosed space to diminish by 60 dB.
  * Resonance is the intensification and prolongation of sound produced by sympathetic vibration, the vibration induced in one body by the vibrations of exactly the same period in a neighboring body. 

## **A.16 SOUND CONTROL**

Noise is any sound that is unwanted, annoying, or discordant, or that interferes with one's hearing of something.  Whenever possible, undesirable noises should be controlled at their source. 

### **Noise Reduction**

The required reduction in noise level from one space to another depends on the level of the sound source and the level of the sound's intrusion that may be acceptable to the listener.  The perceived or apparent sound level in a space is dependent on:

  * White noise is an unvarying, unobtrusive sound having the same intensity for all frequencies of a given band, used to mask or obliterate unwanted sound. 

## **A.17 SOUND CONTROL**

### **Transmission Loss**

  * Transmission loss (TL) is a measure of the performance of a building material or construction assembly in preventing the transmission of airborne sound, equal to the reduction in sound intensity as it passes through the material or assembly when tested at all 1/3 octave band center frequencies from 125 to 4000 Hz: expressed in decibels. 
  * Average TL is a single-number rating of the performance of a building material or construction assembly in preventing the transmission of airborne sound, equal to the average of its TL values at nine test frequencies. 

### **Impact Noise**

Impact noise is structure-borne sound generated by physical impact, as by footsteps or the moving of furniture. 

  * Impact insulation class (IIC) is a single-number rating of the performance of a floor-ceiling construction in preventing the transmission of impact noise.  The higher the IIC rating, the more effective is the construction in isolating impact noise.  The IIC rating replaces the previously used Impact Noise Rating (INR) and is approximately equal to the INR rating + 51 dB for a given construction. 

Three factors enhance the TL rating of a construction assembly: separation into layers, mass, and absorptive capacity. 

  * Acoustic mass resists the transmission of sound by the inertia and elasticity of the transmitting medium.  In general, the heavier and more dense a body, the greater its resistance to sound transmission. 
  * Absorption coefficient is a measure of the efficiency of a material in absorbing sound at a specified frequency, equal to the fractional part of the incident sound energy at that frequency absorbed by the material. 

**CSI MasterFormat 09 80 00: Acoustic Treatment**

## **A.18 GRAPHIC MATERIAL SYMBOLS**

## **A.19 CSI MASTERFORMAT**

The Construction Specifications Institute (CSI) created MasterFormat® to standardize information about construction requirements, products, and activities, and facilitate communication among architects, contractors, specifiers, and suppliers.  MasterFormat® is the most widely adopted specification-writing standard for commercial design and construction projects in North America. 

Along with her sister organization, Construction Specifications Canada (CSC), CSI issued a new edition of MasterFormat® in 2004 that adopted a six-digit numbering scheme to provide more flexibility and room for expansion than the five-digit numbers of the 1995 edition could provide.  The 2004 edition also increased from 16 to 50 divisions to reflect innovations in and growing complexity of the construction industry, such as Building Information Modeling (BIM), life-cycle costing, and issues of pollution, remediation, and maintenance.  Updates have been published in 2010 and 2012. 

MasterFormat® organizes a master list of section numbers and subject titles into two major groups: the Procurement and Contracting Requirements Group (Division 00) and the Specifications Group, which is further subdivided into five subgroups:

  * General Requirements Subgroup: Division 01
  * Facility Construction Subgroup: Divisions 02 through 19
  * Facility Services Subgroup: Divisions 20 through 29
  * Site and Infrastructure Subgroup: Divisions 30 through 39
  * Process Equipment Subgroup: Divisions 40 through 49

There are a total of 50 level-one titles or divisions, some of which are held in reserve for future use.  Each division consists of sections defined by a number and title and arranged in levels depending on their breadth and depth of coverage. 

### **SPECIFICATIONS GROUP  
Facility Construction Subgroup**

**DIVISION 04 – MASONRY**

### **PROCUREMENT AND CONTRACTING REQUIREMENTS GROUP**

**DIVISION 00 – PROCUREMENT AND CONTRACTING REQUIREMENTS**

00 10 00 Solicitation  
00 20 00 Instructions for Procurement  
00 30 00 Available Information  
00 40 00 Procurement Forms and Supplements  
00 50 00 Contracting Forms and Supplements  
00 60 00 Project Forms  
00 70 00 Conditions of the Contract  
00 80 00 Unassigned  
00 90 00 Revisions, Clarifications, and Modifications

### **SPECIFICATIONS GROUP  
General Requirements Subgroup**

**DIVISION 01 – GENERAL REQUIREMENTS**

01 00 00 General Requirements  
01 10 00 Summary  
01 20 00 Price and Payment Procedures  
01 30 00 Administrative Requirements  
01 40 00 Quality Requirements  
01 50 00 Temporary Facilities and Controls  
01 60 00 Product Requirements  
01 70 00 Execution and Closeout Requirements  
01 80 00 Performance Requirements  
01 90 00 Life-Cycle Activities

### **Facility Construction Subgroup**

**DIVISION 02 – EXISTING CONDITIONS**

02 00 00 Existing Conditions  
02 10 00 Unassigned  
02 20 00 Assessment  
02 30 00 Subsurface Investigation  
02 40 00 Demolition and Structure Moving  
02 50 00 Site Remediation  
02 60 00 Contaminated Site Material Removal  
02 70 00 Water Remediation  
02 80 00 Facility Remediation  
02 90 00 Unassigned

**DIVISION 03 – CONCRETE**

03 00 00 Concrete  
03 10 00 Concrete Forming and Accessories  
03 20 00 Concrete Reinforcing  
03 30 00 Cast-in-Place Concrete  
03 40 00 Precast Concrete  
03 50 00 Cast Decks and Underlayment  
03 60 00 Grouting  
03 70 00 Mass Concrete  
03 80 00 Concrete Cutting and Boring  
03 90 00 Unassigned

## **A.20 CSI MASTERFORMAT**

**DIVISION 04 – MASONRY**

04 00 00 Masonry  
04 10 00 Unassigned  
04 20 00 Unit Masonry  
04 30 00 Unassigned  
04 40 00 Stone Assemblies  
04 50 00 Refractory Masonry  
04 60 00 Corrosion-Resistant Masonry  
04 70 00 Manufactured Masonry  
04 80 00 Unassigned  
04 90 00 Unassigned

**DIVISION 05 – METALS**

05 00 00 Metals  
05 10 00 Structural Metal Framing  
05 20 00 Metal Joists  
05 30 00 Metal Decking  
05 40 00 Cold-Formed Metal Framing  
05 50 00 Metal Fabrications  
05 60 00 Unassigned  
05 70 00 Decorative Metal  
05 80 00 Unassigned  
05 90 00 Unassigned

**DIVISION 06 – WOOD, PLASTICS, AND COMPOSITES**

06 00 00 Wood, Plastics, and Composites  
06 10 00 Rough Carpentry  
06 20 00 Finish Carpentry  
06 30 00 Unassigned  
06 40 00 Architectural Woodwork  
06 50 00 Structural Plastics  
06 60 00 Plastic Fabrications  
06 70 00 Structural Composites  
06 80 00 Composite Fabrications  
06 90 00 Unassigned

**DIVISION 07 – THERMAL AND MOISTURE PROTECTION**

07 00 00 Thermal and Moisture Protection  
07 10 00 Dampproofing and Waterproofing  
07 20 00 Thermal Protection  
07 25 00 Weather Barriers  
07 30 00 Steep Slope Roofing  
07 40 00 Roofing and Siding Panels  
07 50 00 Membrane Roofing  
07 60 00 Flashing and Sheet Metal  
07 70 00 Roof and Wall Specialties and Accessories  
07 80 00 Fire and Smoke Protection  
07 90 00 Joint Protection

**DIVISION 08 – OPENINGS**

08 00 00 Openings  
08 10 00 Doors and Frames  
08 20 00 Unassigned  
08 30 00 Specialty Doors and Frames  
08 40 00 Entrances, Storefronts, and Curtain Walls  
08 50 00 Windows  
08 60 00 Roof Windows and Skylights  
08 70 00 Hardware  
08 80 00 Glazing  
08 90 00 Louvers and Vents

**DIVISION 09 – FINISHES**

09 00 00 Finishes  
09 10 00 Unassigned  
09 20 00 Plaster and Gypsum Board  
09 30 00 Tiling  
09 40 00 Unassigned  
09 50 00 Ceilings  
09 60 00 Flooring  
09 70 00 Wall Finishes  
09 80 00 Acoustic Treatment  
09 90 00 Painting and Coating

**DIVISION 10 – SPECIALTIES**

10 00 00 Specialties  
10 10 00 Information Specialties  
10 20 00 Interior Specialties  
10 30 00 Fireplaces and Stoves  
10 40 00 Safety Specialties  
10 50 00 Storage Specialties  
10 60 00 Unassigned  
10 70 00 Exterior Specialties  
10 80 00 Other Specialties  
10 90 00 Unassigned

**DIVISION 11 – EQUIPMENT**

11 00 00 Equipment  
11 10 00 Vehicle and Pedestrian Equipment  
11 15 00 Security, Detention and Banking Equipment  
11 20 00 Commercial Equipment  
11 30 00 Residential Equipment  
11 40 00 Foodservice Equipment  
11 50 00 Educational and Scientific Equipment  
11 60 00 Entertainment Equipment  
11 65 00 Athletic and Recreational Equipment  
11 70 00 Healthcare Equipment  
11 80 00 Collection and Disposal Equipment  
11 90 00 Other Equipment

**DIVISION 12 – FURNISHINGS**

12 00 00 Furnishings  
12 10 00 Art  
12 20 00 Window Treatments  
12 30 00 Casework  
12 40 00 Furnishings and Accessories  
12 50 00 Furniture  
12 60 00 Multiple Seating  
12 70 00 Unassigned  
12 80 00 Unassigned  
12 90 00 Other Furnishings

**DIVISION 13 – SPECIAL CONSTRUCTION**

13 00 00 Special Construction  
13 10 00 Special Facility Components  
13 20 00 Special Purpose Rooms  
13 30 00 Special Structures  
13 40 00 Integrated Construction  
13 50 00 Special Instrumentation  
13 60 00 Unassigned  
13 70 00 Unassigned  
13 80 00 Unassigned  
13 90 00 Unassigned

**DIVISION 14 – CONVEYING EQUIPMENT**

14 00 00 Conveying Equipment  
14 10 00 Dumbwaiters  
14 20 00 Elevators  
14 30 00 Escalators and Moving Walks  
14 40 00 Lifts  
14 50 00 Unassigned  
14 60 00 Unassigned  
14 70 00 Turntables  
14 80 00 Scaffolding  
14 90 00 Other Conveying Equipment

**DIVISIONS 15–19 RESERVED**

### **Facility Services Subgroup**

**DIVISION 20 – RESERVED  
DIVISION 21 – FIRE SUPPRESSION**

21 00 00 Fire Suppression  
21 10 00 Water-Based Fire-Suppression Systems  
21 20 00 Fire-Extinguishing Systems  
21 30 00 Fire Pumps  
21 40 00 Fire-Suppression Water Storage  
21 50 00 Unassigned  
21 60 00 Unassigned  
21 70 00 Unassigned  
21 80 00 Unassigned  
21 90 00 Unassigned

## **A.21 CSI MASTERFORMAT**

**DIVISION 22 – PLUMBING**

22 00 00 Plumbing  
22 10 00 Plumbing Piping  
22 20 00 Unassigned  
22 30 00 Plumbing Equipment  
22 40 00 Plumbing Fixtures  
22 50 00 Pool and Fountain Plumbing Systems  
22 60 00 Gas and Vacuum Systems for Laboratory and Healthcare Facilities  
22 70 00–22 90 00 Unassigned

**DIVISION 23 – HEATING, VENTILATING, AND AIR-CONDITIONING (HVAC)**

23 00 00 Heating, Ventilating, and Air-Conditioning (HVAC)  
23 10 00 Facility Fuel Systems  
23 20 00 HVAC Piping and Pumps  
23 30 00 HVAC Air Distribution  
23 40 00 HVAC Air Cleaning Devices  
23 50 00 Central Heating Equipment  
23 60 00 Central Cooling Equipment  
23 70 00 Central HVAC Equipment  
23 80 00 Decentralized HVAC Equipment  
23 90 00 Unassigned

**DIVISION 24 – RESERVED  
DIVISION 25 – INTEGRATED AUTOMATION**

25 00 00 Integrated Automation  
25 10 00 Integrated Automation Network Equipment  
25 20 00 Unassigned  
25 30 00 Integrated Automation Instrumentation and Terminal Devices  
25 40 00 Unassigned  
25 50 00 Integrated Automation Facility Controls  
25 60 00 Unassigned  
25 70 00 Unassigned  
25 80 00 Unassigned  
25 90 00 Integrated Automation Control Sequences

**DIVISION 26 – ELECTRICAL**

26 00 00 Electrical  
26 10 00 Medium-Voltage Electrical Distribution  
26 20 00 Low-Voltage Electrical Distribution  
26 30 00 Facility Electrical Power Generating and Storing Equipment  
26 40 00 Electrical and Cathodic Protection  
26 50 00 Lighting  
26 60 00 Unassigned  
26 70 00 Unassigned  
26 80 00 Unassigned  
26 90 00 Unassigned

**DIVISION 27 – COMMUNICATIONS**

27 00 00 Communications  
27 10 00 Structured Cabling  
27 20 00 Data Communications  
27 30 00 Voice Communications  
27 40 00 Audio-Video Communications  
27 50 00 Distributed Communications and Monitoring Systems  
27 60 00–27 90 00 Unassigned

**DIVISION 28 – ELECTRONIC SAFETY AND SECURITY**

28 00 00 Electronic Safety and Security  
28 10 00 Electronic Access Control and Intrusion Detection  
28 20 00 Electronic Surveillance  
28 30 00 Electronic Detection and Alarm  
28 40 00 Electronic Monitoring and Control  
28 50 00 Unassigned  
28 60 00 Unassigned  
28 70 00 Unassigned  
28 80 00 Unassigned  
28 90 00 Unassigned

**DIVISION 29 – RESERVED**

### **Site and Infrastructure Subgroup**

**DIVISION 30 – RESERVED  
DIVISION 31 – EARTHWORK**

31 00 00 Earthwork  
31 10 00 Site Clearing  
31 20 00 Earth Moving  
31 30 00 Earthwork Methods  
31 40 00 Shoring and Underpinning  
31 50 00 Excavation Support and Protection  
31 60 00 Special Foundations and Load-Bearing Elements  
31 70 00 Tunneling and Mining  
31 80 00 Unassigned  
31 90 00 Unassigned

**DIVISION 32 – EXTERIOR IMPROVEMENTS**

32 00 00 Exterior Improvements  
32 10 00 Bases, Ballasts, and Paving  
32 20 00 Unassigned  
32 30 00 Site Improvements  
32 40 00 Unassigned  
32 50 00 Unassigned  
32 60 00 Unassigned  
32 70 00 Wetlands  
32 80 00 Irrigation  
32 90 00 Planting

**DIVISION 33 – UTILITIES**

33 00 00 Utilities  
33 10 00 Water Utilities  
33 20 00 Wells  
33 30 00 Sanitary Sewerage Utilities  
33 40 00 Storm Drainage Utilities  
33 50 00 Fuel Distribution Utilities  
33 60 00 Hydronic and Steam Energy Utilities  
33 70 00 Electrical Utilities  
33 80 00 Communications Utilities  
33 90 00 Unassigned

**DIVISION 34 – TRANSPORTATION**

34 00 00 Transportation  
34 10 00 Guideways/Railways  
34 20 00 Traction Power  
34 30 00 Unassigned  
34 40 00 Transportation Signaling and Control Equipment  
34 50 00 Transportation Fare Collection Equipment  
34 60 00 Unassigned  
34 70 00 Transportation Construction and Equipment  
34 80 00 Bridges  
34 90 00 Unassigned

**DIVISION 35 – WATERWAY AND MARINE CONSTRUCTION**

35 00 00 Waterway and Marine Construction  
35 10 00 Waterway and Marine Signaling and Control Equipment  
35 20 00 Waterway and Marine Construction and Equipment  
35 30 00 Coastal Construction  
35 40 00 Waterway Construction and Equipment  
35 50 00 Marine Construction and Equipment  
35 60 00 Unassigned  
35 70 00 Dam Construction and Equipment  
35 80 00 Unassigned  
35 90 00 Unassigned

**DIVISIONS 36–39 RESERVED**

## **A.22 CSI MASTERFORMAT**

### **Process Equipment Subgroup**

**DIVISION 40 – PROCESS INTEGRATION**

40 00 00 Process Integration  
40 10 00 Gas and Vapor Process Piping  
40 20 00 Liquids Process Piping  
40 30 00 Solid and Mixed Materials Piping and Chutes  
40 40 00 Process Piping and Equipment Protection  
40 50 00 Unassigned  
40 60 00 Unassigned  
40 70 00 Unassigned  
40 80 00 Commissioning of Process Systems  
40 90 00 Instrumentation and Control for Process Systems

**DIVISION 41 – MATERIAL PROCESSING AND HANDLING EQUIPMENT**

41 00 00 Material Processing and Handling Equipment  
41 10 00 Bulk Material Processing Equipment  
41 20 00 Piece Material Handling Equipment  
41 30 00 Manufacturing Equipment  
41 40 00 Container Processing and Packaging  
41 50 00 Material Storage  
41 60 00 Mobile Plant Equipment  
41 70 00 Unassigned  
41 80 00 Unassigned  
41 90 00 Unassigned

**DIVISION 42 – PROCESS HEATING, COOLING, AND DRYING EQUIPMENT**

42 00 00 Process Heating, Cooling, and Drying Equipment  
42 10 00 Process Heating Equipment  
42 20 00 Process Cooling Equipment  
42 30 00 Process Drying Equipment  
42 40 00 Unassigned  
42 50 00 Unassigned  
42 60 00 Unassigned  
42 70 00 Unassigned  
42 80 00 Unassigned  
42 90 00 Unassigned

**DIVISION 43 – PROCESS GAS AND LIQUID HANDLING, PURIFICATION, AND STORAGE EQUIPMENT**

43 00 00 Process Gas and Liquid Handling, Purification, and Storage Equipment  
43 10 00 Gas Handling Equipment  
43 20 00 Liquid Handling Equipment  
43 30 00 Gas and Liquid Purification Equipment  
43 40 00 Gas and Liquid Storage  
43 50 00 Unassigned  
43 60 00 Unassigned  
43 70 00 Unassigned  
43 80 00 Unassigned  
43 90 00 Unassigned

**DIVISION 44 – POLLUTION AND WASTE CONTROL EQUIPMENT**

44 00 00 Pollution and Waste Control Equipment  
44 10 00 Air Pollution Control  
44 20 00 Noise Pollution Control  
44 40 00 Water Treatment Equipment  
44 50 00 Solid Waste Control  
44 60 00 Waste Thermal Processing Equipment  
44 70 00 Unassigned  
44 80 00 Unassigned  
44 90 00 Unassigned

**DIVISION 45 – INDUSTRY-SPECIFIC MANUFACTURING EQUIPMENT**

45 00 00 Industry-Specific Manufacturing Equipment  
45 60 00 Unassigned  
45 70 00 Unassigned  
45 80 00 Unassigned  
45 90 00 Unassigned

**DIVISION 46 – WATER AND WASTEWATER EQUIPMENT**

46 00 00 Water and Wastewater Equipment  
46 10 00 Unassigned  
46 20 00 Water and Wastewater Preliminary Treatment Equipment  
46 30 00 Water and Wastewater Chemical Feed Equipment  
46 40 00 Water and Wastewater Clarification and Mixing Equipment  
46 50 00 Water and Wastewater Secondary Treatment Equipment  
46 60 00 Water and Wastewater Advanced Treatment Equipment  
46 70 00 Water and Wastewater Residuals Handling and Treatment  
46 80 00 Unassigned  
46 90 00 Unassigned

**DIVISION 47 – RESERVED**

**DIVISION 48 – ELECTRICAL POWER GENERATION**

48 00 00 Electrical Power Generation  
48 10 00 Electrical Power Generation Equipment  
48 20 00 Unassigned  
48 30 00 Unassigned  
48 40 00 Unassigned  
48 50 00 Unassigned  
48 60 00 Unassigned  
48 70 00 Electrical Power Generation Testing  
48 80 00 Unassigned  
48 90 00 Unassigned

**DIVISION 49 – RESERVED**

## **A.23 UNIFORMAT II**

UNIFORMAT II (ASTM STANDARD E1557-09) provides a consistent reference for the description, economic analysis, and management of buildings during all phases of their life cycle, including planning, programming, design, construction, operations, and disposal.  The format is based on the classification of elements, which are defined as "major components, common to most buildings, that perform a given function, regardless of the design specification, construction method, or materials used."  Examples of functional building elements are foundations, superstructure, stairs, and plumbing.  UNIFORMAT II therefore differs from and complements the MasterFormat® classification system, which is based on products and building materials for detailed quantity takeoffs of materials and tasks associated with the construction, operation, and maintenance of buildings. 

The UNIFORMAT II organizational structure assumes that design information at the schematic phase can be communicated more effectively by functional building elements rather than by building material or product, and that an elemental classification system would be more easily understood by clients and others who do not have a technical background.  A comprehensive and consistent classification of functional elements also enables the necessary cost information to be evaluated in the early stages of the design process, thus assuring faster and more accurate economic analysis of alternative design decisions early in the beginning stages of the project. 

UNIFORMAT II classifies building elements into three hierarchical levels using an alphanumeric designation.  There are seven Level 1 groups:

  * Group A: Substructure, including Foundations & Basement Construction
  * Group B: Shell, including Superstructure, Exterior Enclosure & Roofing
  * Group C: Interiors, including Interior Construction, Stairs & Interior Finishes
  * Group D: Conveying, Plumbing, HVAC, Fire Protection & Electrical Systems
  * Group E: Equipment & Furnishings
  * Group F: Special Construction & Demolition
  * Group G: Building Sitework

Each Major Group Element is broken down into Level 2 Group Elements (B10, B20...) and Level 3 Individual Elements (B1010, B1020, B2010, B2020...).  A Level 4 is proposed to break the individual elements into yet smaller Sub-elements B1011, B1012, B1013...). 

**ASTM UNIFORMAT II Classification for Building Elements (E1557-09)**  
---  
**Level 1 Major Group Elements** | **Level 2 Group Elements** | **Level 3 Individual Elements**  
A. SUBSTRUCTURE | A10 Foundations | A1010 Standard Foundations  
|  | A1020 Special Foundations  
|  | A1030 Slab on Grade  
| A20 Basement Construction | A2010 Basement Excavation  
|  | A2020 Basement Walls  
B. SHELL | B10 Superstructure | B1010 Floor Construction  
|  | B1020 Roof Construction  
| B20 Exterior Enclosure | B2010 Exterior Walls  
|  | B2020 Exterior Windows  
|  | B2030 Exterior Doors  
| B30 Roofing | B3010 Roof Coverings  
|  | B3020 Roof Openings  
C. INTERIORS | C10 Interior Construction | C1010 Partitions  
|  | C1020 Interior Doors  
|  | C1030 Specialties  
| C20 Stairs | C2010 Stair Construction  
|  | C2020 Stair Finishes  
| C30 Interior Finishes | C3010 Wall Finishes  
|  | C3020 Floor Finishes  
|  | C3030 Ceiling Finishes  
|  | C3040 Interior Coatings and Special Finishes

## **A.24 UNIFORMAT II**

**ASTM UNIFORMAT II Classification for Building Elements (E1557-09)**  
---  
**Level 1 Major Group Elements** | **Level 2 Group Elements** | **Level 3 Individual Elements**  
D. SERVICES | D10 Conveying | D1010 Elevators & Lifts  
|  | D1020 Escalators & Moving Walks  
|  | D1090 Other Conveying Systems  
| D20 Plumbing | D2010 Plumbing Fixtures  
|  | D2020 Domestic Water Distribution  
|  | D2030 Sanitary Waste  
|  | D2040 Rain Water Drainage  
|  | D2090 Other Plumbing Systems  
| D30 HVAC | D3010 Energy Supply  
|  | D3020 Heat Generating Systems  
|  | D3030 Cooling Generating Systems  
|  | D3040 Distribution Systems  
|  | D3050 Terminal & Package Units  
|  | D3060 Controls & Instrumentation  
|  | D3070 Systems Testing & Balancing  
|  | D3090 Other HVAC Systems & Equipment  
| D40 Fire Protection | D4010 Fire Alarm and Detection Systems  
|  | D4020 Fire Suppression Water Supply & Equipment  
|  | D4030 Standpipe Systems  
|  | D4040 Sprinklers  
|  | D4050 Fire Protection Specialties  
|  | D4090 Other Fire Protection Systems  
| D50 Electrical | D5010 Electrical Service & Distribution  
|  | D5020 Lighting and Branch Wiring  
|  | D5030 Communications & Security  
|  | D5090 Other Electrical Systems  
E. EQUIPMENT & FURNISHINGS | E10 Equipment | E1010 Commercial Equipment  
|  | E1020 Institutional Equipment  
|  | E1030 Vehicular Equipment  
|  | E1040 Government Furnished Equipment  
|  | E1090 Other Equipment  
| E20 Furnishings | E2010 Fixed Furnishings  
|  | E2020 Movable Furnishings  
F. SPECIAL CONSTRUCTION & DEMOLITION | F10 Special Construction | F1010 Special Structures  
|  | F1020 Integrated Construction  
|  | F1030 Special Construction Systems  
|  | F1040 Special Facilities  
|  | F1050 Special Controls & Instrumentation  
| F20 Selective Building Demolition | F2010 Building Elements Demolition  
|  | F2020 Hazardous Components Abatement

## **A.25 UNIFORMAT II**

**ASTM UNIFORMAT II Classification for Building-Related Sitework (E1557-09)**  
---  
**Level 1 Major Group Elements** | **Level 2 Group Elements** | **Level 3 Individual Elements**  
G. BUILDING SITEWORK | G10 Site Preparation | G1010 Site Clearing  
|  | G1020 Site Demolition & Relocations  
|  | G1030 Site Earthwork  
|  | G1040 Hazardous Waste Remediation  
| G20 Site Improvements | G2010 Roadways  
|  | G2020 Parking Lots  
|  | G2030 Pedestrian Paving  
|  | G2040 Site Development  
|  | G2050 Landscaping  
| G30 Site Civil/Mechanical Utilities | G3010 Water Supply  
|  | G3020 Sanitary Sewer  
|  | G3030 Storm Sewer  
|  | G3040 Heating Distribution  
|  | G3050 Cooling Distribution  
|  | G3060 Fuel Distribution  
|  | G3090 Other Site Mechanical Utilities  
| G40 Site Electrical Utilities | G4010 Electrical Distribution  
|  | G4020 Site Lighting  
|  | G4030 Site Communications & Security  
|  | G4090 Other Site Electrical Utilities  
| G90 Other Site Construction | G9010 Service and Pedestrian Tunnels  
|  | G9090 Other Site Systems & Equipment  
Z. GENERAL CONDITIONS | Z10 General Requirements |   
| Z20 Bidding Requirements |   
| Z90 Project Cost Estimate |

## **A.26 LEED GREEN BUILDING RATING SYSTEM**

### **LEED ® 2009  
For New Construction & Major Renovations  
Version 2.2**

### **Sustainable Sites (26 Possible Points)**

SS Prerequisite 1 Construction Activity Pollution Prevention Required  
SS Credit 1 Site Selection 1  
SS Credit 2 Development Density & Community Connectivity 5  
SS Credit 3 Brownfield Redevelopment 1  
SS Credit 4.1 Alternative Transportation – Public Transportation Access 6  
SS Credit 4.2 Alternative Transportation – Bicycle Storage & Changing Rooms 1  
SS Credit 4.3 Alternative Transportation – Low Emitting & Fuel Efficient Vehicles 3  
SS Credit 4.4 Alternative Transportation – Parking Capacity 2  
SS Credit 5.1 Site Development – Protect or Restore Habitat 1  
SS Credit 5.2 Site Development – Maximize Open Space 1  
SS Credit 6.1 Stormwater Design – Quantity Control 1  
SS Credit 6.2 Stormwater Design – Quality Control 1  
SS Credit 7.1 Heat Island Effect – Non-Roof 1  
SS Credit 7.2 Heat Island Effect – Roof 1  
SS Credit 8 Light Pollution Reduction 1

### **Water Efficiency (10 Possible Points)**

WE Prerequisite 1 Water Use Reduction–20% Reduction  
WE Credit 1.2 Water Efficient Landscaping 2–4  
WE Credit 2 Innovative Wastewater Technologies 2  
WE Credit 3.1 Water Use Reduction 2–4

### **Energy & Atmosphere (35 Possible Points)**

EA Prerequisite 1 Fundamental Commissioning of the Building Energy  
Systems Required  
EA Prerequisite 2 Minimum Energy Performance Required  
EA Prerequisite 3 Fundamental Refrigerant Management Required  
EA Credit 1 Optimize Energy Performance 1–19  
EA Credit 2 On-Site Renewable Energy 1–7  
EA Credit 3 Enhanced Commissioning 2  
EA Credit 4 Enhanced Refrigerant Management 2  
EA Credit 5 Measurement & Verification 3  
EA Credit 6 Green Power 2

### **Materials & Resources (14 Possible Points)**

MR Prerequisite 1 Storage & Collection of Recyclables Required  
MR Credit 1.1 Building Reuse – Maintain Existing Walls, Floors and Roof 1–3  
MR Credit 1.2 Building Reuse – Maintain Existing Interior Nonstructural Elements 1  
MR Credit 2 Construction Waste Management 1–2  
MR Credit 3 Materials Reuse 1–2  
MR Credit 4 Recycled Content 1–2  
MR Credit 5 Regional Materials 1–2  
MR Credit 6 Rapidly Renewable Materials 1  
MR Credit 7 Certified Wood 1

### **Indoor Environmental Quality (15 Possible Points)**

EQ Prerequisite 1 Minimum Indoor Air Quality (IAQ) Performance Required  
EQ Prerequisite 2 Environmental Tobacco Smoke (ETS) Control Required  
EQ Credit 1 Outdoor Air Delivery Monitoring 1  
EQ Credit 2 Increased Ventilation 1  
EQ Credit 3.1 Construction IAQ Management Plan, During Construction 1  
EQ Credit 3.2 Construction IAQ Management Plan, Before Occupancy 1  
EQ Credit 4.1 Low-Emitting Materials – Adhesives & Sealants 1  
EQ Credit 4.2 Low-Emitting Materials – Paints & Coatings 1  
EQ Credit 4.3 Low-Emitting Materials – Flooring Systems 1  
EQ Credit 4.4 Low-Emitting Materials – Composite Wood & Agrifiber Products 1  
EQ Credit 5 Indoor Chemical & Pollutant Source Control 1  
EQ Credit 6.1 Controllability of Systems – Lighting 1  
EQ Credit 6.2 Controllability of Systems – Thermal Comfort 1  
EQ Credit 7.1 Thermal Comfort – Design 1  
EQ Credit 7.2 Thermal Comfort – Verification 1  
EQ Credit 8.1 Daylight & Views – Daylight 1  
EQ Credit 8.2 Daylight & Views – Views 1

### **Innovation & Design Process (6 Possible Points)**

ID Credit 1 Innovation in Design 1–5  
ID Credit 2 LEED Accredited Professional 1

### **Regional Priority (4 Possible Points)**

RP Credit 1 Regional Priority 1–4

### **100 base points +  
6 possible Innovation in Design and 4 Regional Priority points**

To receive LEED certification, a building project must meet certain prerequisites and performance benchmarks or credits within each category.  Projects are awarded Certified, Silver, Gold, or Platinum certification depending on the number of credits they achieve. 

  * Certified 40–49 points
  * Silver 50–59 points
  * Gold 60–79 points
  * Platinum 80 points and above

## **A.27 PROFESSIONAL & TRADE ASSOCIATIONS**

### **Professional & Trade Associations**

American Institute of Architects  
www.aia.org

American Institute of Building Design  
www.aibd.org

American Society of Civil Engineers  
www.asce.org

American Society of Interior Designers  
www.asid.org

American Society of Landscape Architects  
www.asla.org

Architecture 2030  
www.architecture2030.org

Associated General Contractors of America  
www.agc.org

Building Research Establishment  
www.bre.co.uk

Canadian Construction Association  
www.cca-acc.com

Construction Management Association of America  
www.cmaanet.org

Construction Specifications Canada  
www.csc-dcc.ca

Construction Specifications Institute  
www.csinet.org

Environmental Protection Agency  
www.epa.gov

Green Building Institute  
<http://greenbuildingnetwork.groupsite.com/>

Home Innovation Research Labs  
www.homeinnovation.com

Insurance Services Office  
www.iso.com

McGraw-Hill Construction  
www.construction.com

National Council of Architectural Registration Boards  
www.ncarb.org

National Institute of Building Sciences  
www.nibs.org

National Society of Professional Engineers  
www.nspe.org

Partnership for Advancing Technology in Housing  
www.pathnet.org

Royal Architectural Institute of Canada  
www.raic.org

Society of American Registered Architects  
www.sara-national.org

Structural Engineers Association of California  
www.seaoc.org

Superintendent of Documents U.S. Government Printing Office  
www.gpoaccess.gov

Urban Land Institute  
www.uli.org

U.S. Department of Energy Energy Efficiency and Renewable Energy  
www.eere.energy.gov

U.S. Department of Housing and Urban Development  
www.portal.hud.gov

U.S. Department of Justice 2010 ADA Standards for Accessible Design  
<http://www.ada.gov>

U.S. Department of Labor Occupational Safety and Health Administration  
www.osha.gov

U.S. Green Building Council  
new.usgbc.org

### **CSI Division 03 • Concrete**

American Concrete Institute  
www.concrete.org

American Society for Concrete Contractors  
www.ascconline.org

Architectural Precast Association  
www.archprecast.org

Concrete Reinforcing Steel Institute  
www.crsi.org

National Precast Concrete Association  
<http://precast.org>

Portland Cement Association  
www.cement.org

Post-Tensioning Institute  
www.post-tensioning.org

Precast/Prestressed Concrete Institute  
www.pci.org

Wire Reinforcement Institute  
www.wirereinforcementinstitute.org

### **CSI Division 04 • Masonry**

Brick Industry Association  
www.brickinfo.org

Expanded Shale, Clay and Slate Institute  
www.escsi.org

Indiana Limestone Institute of America  
www.iliai.com

International Masonry Institute  
www.imiweb.org

Marble Institute of America  
www.marble-institute.com

Masonry Institute of America  
www.masonryinstitute.org

National Concrete Masonry Association  
www.ncma.org

## **A.28 PROFESSIONAL & TRADE ASSOCIATIONS**

### **CSI Division 05 • Metals**

Aluminum Association  
www.aluminum.org

American Institute of Steel Construction  
www.aisc.org

American Iron and Steel Institute  
www.steel.org

American Welding Society  
www.aws.org

American Zinc Association  
www.zinc.org

Cold-Formed Steel Engineers Institute  
www.cfsei.org

Copper Development Association  
www.copper.org

National Association of Architectural Metals Manufacturers  
www.naamm.org

Specialty Steel Institute of North America  
www.ssina.com

Steel Deck Institute  
www.sdi.org

Steel Joist Institute  
<http://steeljoist.org>

### **CSI Division 06 • Wood, Plastics and Composites**

American Forest & Paper Association  
www.afandpa.org

American Institute of Timber Construction  
www.aitc-glulam.org

American Plywood Association  
www.apawood.org

American Wood Council  
www.awc.org

American Wood-Preservers Association  
www.awpa.com

Architectural Woodwork Institute  
www.awinet.org

Canadian Wood Council  
www.cwc.ca

Ceiba Foundation for Tropical Conservation  
www.ceiba.org

Composite Panel Association  
<http://compositepanel.org>

Forest Products Laboratory USDA Forest Service  
www.fpl.fs.fed.us

Forest Stewardship Council  
www.us.fsc.org

National Hardwood Lumber Association  
www.nhla.org

Northeastern Lumber Manufacturers Association  
www.nelma.org

Society of the Plastics Industry  
www.plasticsindustry.org

Southern Forest Products Association  
www.sfpa.org

Structural Building Components Association  
www.sbcindustry.com

Western Red Cedar Lumber Association  
www.wrcla.org

Western Wood Products Association  
www2.wwpa.org

### **CSI Division 07 • Thermal and Moisture Protection**

Adhesive and Sealant Council  
www.ascouncil.org

Asphalt Roofing Manufacturers Association  
www.asphaltroofing.org

Cellulose Insulation Manufacturers Association  
www.cellulose.org

EIFS Industry Members Association  
www.eima.com

National Roofing Contractors Association  
www.nrca.net

North American Insulation Manufacturers Association  
www.naima.org

Perlite Institute  
www.perlite.org

Polyisocyanurate Insulation Manufacturers Association  
www.polyiso.org

Roof Consultants Institute  
www.rci-online.org

Structural Insulated Panel Association  
www.sips.org

Stucco Manufacturers Association  
www.stuccomfgassoc.com

Vermiculite Association  
www.vermiculite.org

### **CSI Division 08 • Openings**

American Architectural Manufacturers Association  
www.aamanet.org

American Hardware Manufacturers Association  
www.ahma.org

Builders Hardware Manufacturers Association  
www.buildershardware.com

Door and Hardware Institute  
www.dhi.org

Glass Association of North America  
www.glasswebsite.com

National Fenestration Rating Council  
www.nfrc.org

## **A.29 PROFESSIONAL & TRADE ASSOCIATIONS**

National Glass Association  
www.glass.org

Steel Door Institute  
www.steeldoor.org

Steel Window Institute  
www.steelwindows.com

Window and Door Manufacturers Association  
www.wdma.com

### **CSI Division 09 • Finishes**

American Coatings Association  
www.paint.org

Association of the Wall and Ceiling Industries International  
www.awci.org

Carpet and Rug Institute  
www.carpet-rug.com

Ceilings and Interior Systems Construction Association  
www.cisca.org

Ceramic Tile Distributors Association  
www.ctdahome.org

Gypsum Association  
www.gypsum.org

Hardwood Manufacturers Association  
www.hardwood.org

Hardwood Plywood and Veneer Association  
www.hpva.org

Maple Flooring Manufacturers Association  
www.maplefloor.org

National Council of Acoustical Consultants  
www.ncac.com

National Terrazzo and Mosaic Association  
www.ntma.com

National Wood Flooring Association  
www.woodfloors.org

Painting and Decorating Contractors of America  
www.pdca.org

Porcelain Enamel Institute  
www.porcelainenamel.com

Resilient Floor Covering Institute  
www.rfci.com

Terrazzo Tile and Marble Association of Canada  
www.ttmac.com

Tile Council of North America  
www.tcnatile.com

Vinyl Institute  
www.vinylinfo.org

Wallcoverings Association  
www.wallcoverings.org

### **CSI Division 10 • Specialties**

Kitchen Cabinet Manufacturers Association  
www.kcma.org

National Kitchen and Bath Association  
www.nkba.org

### **CSI Division 11 • Equipment**

American Society of Safety Engineers  
www.asse.org

Association of Home Appliance Manufacturers  
www.aham.org

Commercial Food Equipment Service Association  
www.cfesa.com

National Solid Wastes Management Association  
www.nswma.org

Solid Waste Association of North America  
www.swana.org

### **CSI Division 12 • Furnishings**

American Society of Furniture Designers  
www.asfd.com

Business and Institutional Furniture Manufacturers Association  
www.bifma.org

Home Furnishings International Association  
www.hfia.com

Industrial Fabrics Association International  
www.ifai.com

International Furnishings and Design Association  
www.ifda.com

International Interior Design Association  
www.iida.org

Specialty Steel Industry of North America  
www.ssina.com

### **CSI Division 13 • Special Construction**

American Fire Sprinkler Association  
www.firesprinkler.org

Fire Suppression Systems Association  
www.fssa.net

Metal Building Manufacturers Association  
www.mbma.com

Modular Building Institute  
www.modular.org

National Fire Protection Association  
www.nfpa.org

Steel Construction Institute  
www.steel-sci.org

## **A.30 PROFESSIONAL & TRADE ASSOCIATIONS**

### **CSI Division 14 • Conveying Systems**

Conveyor Equipment Manufacturers Association  
www.cemanet.org

Material Handling Institute  
www.mhia.org

National Elevator Industry  
www.neii.org

National Association of Elevator Safety Authorities  
www.naesai.org

National Association of Elevator Contractors  
www.naec.org

### **CSI Division 23 • Heating, Ventilating, and Air-Conditioning (HVAC)**

American Gas Association  
www.aga.org

American Society of Heating, Refrigeration, and Air-Conditioning Engineers  
www.ashrae.org

American Society of Mechanical Engineers  
www.asme.org

Home Ventilating Institute  
www.hvi.org

### **CSI Division 26 • Electrical**

Illuminating Engineering Society of North America  
www.iesna.org

International Association of Lighting Designers  
www.iald.org

National Electrical Manufacturers Association  
www.nema.org

### **CSI Division 32 • Exterior Improvements**

American Concrete Pavement Association  
www.pavement.com

American Concrete Pipe Association  
www.concrete-pipe.org

American Nursery and Landscape Association  
www.anla.org

American Society of Sanitary Engineering  
www.asse-plumbing.org

Asphalt Institute  
www.asphaltinstitute.org

Asphalt Recycling & Reclaiming Association  
www.arra.org

Construction Materials Recycling Association  
www.cdrecycling.org

Deep Foundations Institute  
www.dfi.org

International Association of Foundation Drilling  
www.adsc-iafd.com

Plumbing and Drainage Institute  
www.pdionline.org

### **Sponsoring Organizations for Model Codes and Standards**

American National Standards Institute  
www.ansi.org

American Society for Testing and Materials  
www.astm.org

American Society of Safety Engineers  
www.asse.org

International Association of Plumbing and Mechanical Officials  
www.iapmo.org

International Code Council  
www.iccsafe.org

International Organization for Standardization  
www.iso.org

National Institute of Standards and Technology  
www.nist.gov

National Research Council of Canada  
www.nrc-cnrc.gc.ca

Underwriters' Laboratories  
www.ul.com

# Bibliography

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  5.  Ambrose, James, and Jeffrey E. Ollswang.  Simplified Design for Building Sound Control.  John Wiley & Sons, 1995. 
  6.  Ambrose, James, and Patrick Tripeny.  Simplified Design of Concrete Structures, 8th Edition.  John Wiley & Sons, 2007. 
  7.  Ambrose, James.  Simplified Design of Masonry Structures.  John Wiley & Sons, 1997. 
  8.  Ambrose, James, and Patrick Tripeny.  Simplified Design of Steel Structures, 8th Edition.  John Wiley & Sons, 2007. 
  9.  Ambrose, James, and Harry Parker.  Simplified Design of Wood Structures, 6th Edition.  John Wiley & Sons, 2009. 
  10.  Ambrose, James, and Patrick Tripeny.  Simplified Engineering for Architects and Builders, 11th Edition.  John Wiley & Sons, 2010. 
  11.  American Concrete Institute.  Building Code Requirements for Structural Concrete.  ACI, 2008. 
  12.  American Concrete Institute.  Manual of Concrete Practice.  ACI, 2012. 
  13.  American Institute of Architects.  The Environmental Resource Guide.  John Wiley & Sons, 1996.  With supplements (1997, 1998).  Also on CD-Rom, 1999. 
  14.  American Institute of Timber Construction.  Timber Construction Manual, 6th Edition.  John Wiley & Sons, 2012. 
  15.  American Society of Heating, Refrigeration, and Air-conditioning Engineers.  ASHRAE GreenGuide, 3rd Edition.  ASHRAE, 2010. 
  16.  American Society of Heating, Refrigeration, and Air-conditioning Engineers.  ASHRAE Handbook – HVAC Applications.  ASHRAE, 2011. 
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  20.  Butler, Robert Brown.  Standard Handbook of Architectural Engineering.  McGraw-Hill, 1999. 
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  24.  Ching, Francis D.K. A Visual Dictionary of Architecture, 2nd Edition.  John Wiley & Sons, 2011. 
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  26.  Ching, Francis D.K., Barry Onouye, and Doug Zuberbuhler.  Building Structures Illustrated: Patterns, Systems, and Design.  John Wiley & Sons, 2009. 
  27.  Cote, Ron.  NFPA 101: Life Safety Code Handbook 2009.  National Fire Protection Association, 2009. 
  28.  Crosbie, Michael J., and Donald Watson.  Timer-Saver Standards for Architectural Design, 8th Edition.  McGraw-Hill, 2004. 
  29.  DeChiara, Joseph, Julius Panero, and Martin Zelnik.  Time-Saver Standards for Interiors and Space-Planning, 2nd Edition.  McGraw-Hill, 2001. 
  30.  Dilaura, David, Kevin Houser, Richard Mistrick, and Gary Steffy, Eds.  IESNA Lighting Handbook, 9th Edition.  Illuminating Engineering Society of North America, 2011. 
  31.  Dykstra, Alison.  Construction Project Management: A Complete Introduction.  Kirshner Publishing, 2011. 
  32.  Evan Terry Associates.  Pocket Guide to the ADA: Americans with Disabilities Act Accessibility Guidelines for Buildings and Facilities, 3rd Edition.  John Wiley & Sons, 2006. 
  33.  Hacker, John, and Julie A. Gorges.  Residential Steel Design and Construction: Energy Efficiency, Cost Savings, Code Compliance.  McGraw-Hill, 1997. 
  34.  Hewlett, Peter C., editor.  Lea's Chemistry of Cement and Concrete, 4th Edition.  John Wiley & Sons, 2004. 
  35.  Hornbostel, Caleb.  Building Design/Materials and Methods.  Kaplan Publishing, 2007. 
  36.  Hurd, M.K. Formwork for Concrete, 7th Edition.  American Concrete Institute, 2005. 
  37.  International Code Council.  2012 IBC Structural/Seismic Design Manual, Volume 1.  International Code Council, 2006. 
  38.  International Code Council.  2012 International Building Code.  International Code Council, 2011. 
  39.  International Code Council.  2012 International Energy Conservation Code.  International Code Council, 2011. 
  40.  International Code Council.  2012 International Fire Code.  International Code Council, 2011. 
  41.  International Code Council.  2012 International Mechanical Code.  International Code Council, 2011. 
  42.  International Code Council.  2012 International Plumbing Code.  International Code Council, 2011. 
  43.  International Code Council.  2012 International Residential Code for One- and Two- Family Dwellings.  International Code Council, 2011. 
  44.  International Code Council.  Recommended Lateral Force Requirements and Commentary, 7th Edition.  International Code Council, 2002. 
  45.  Liebing, Ralph W. Architectural Working Drawings, 4th Edition.  John Wiley & Sons, 1999. 
  46.  Martin, Leslie D., and Christopher J. Perry.  PCI Design Handbook, 6th Edition.  Prestressed Concrete Institute, 2004. 
  47.  Masonry Society.  Masonry Designers Guide, 6th edition.  Masonry Society, 2010. 
  48.  Masonry Institute of America.  Masonry Design Manual, 4th Edition.  Masonry Institute of America, 2006. 
  49.  Masonry Institute of America.  Reinforced Masonry Engineering Handbook, 6th Edition.  Masonry Institute of America, 2009. 
  50.  Meisel, Art.  LEED Materials: A Resource Guide to Green Building.  Princeton Architectural Press, 2010. 
  51.  Miller, Rex.  Electrician's Pocket Manual.  McGraw-Hill, 2005. 
  52.  Moore, Fuller.  Environmental Control Systems: Heating, Cooling, Lighting.  McGraw-Hill, 1992. 
  53.  National Roofing Contractors Association.  NRCA Roofing and Waterproofing Manual, 5th Edition.  NRCA, 2006. 
  54.  O'Brien, James, and Fredric L. Plotnick.  CPM in Construction Management, 7th Edition.  McGraw-Hill, 2009. 
  55.  Onouye, Barry, and Kevin Kane.  Statics and Strength of Materials for Architecture and Building Construction, 4th Edition.  Prentice Hall, 2011. 
  56.  Onouye, Barry.  Statics and Strength of Materials: Foundations for Structural Design.  Prentice Hall, 2004. 
  57.  Patterson, James.  Simplified Design for Building Fire Safety.  John Wiley & Sons, 1993. 
  58.  Puerifoy, Robert L., Clifford J. Shexnayder, and Aviad Shapira.  Construction Planning, Equipment, and Methods, 8th Edition.  McGraw-Hill, 2010. 
  59.  Ramsey, Charles George, Harold Sleeper, and AIA Staff.  Architectural Graphic Standards, 11th Edition.  John Wiley & Sons, 2007.  Also on CD-Rom, 2007. 
  60.  Reynolds, Donald E., and R.S. Means Staff.  Residential & Light Commercial Construction Standards, 3rd Edition.  R.S. Means, 2008. 
  61.  Richter, H.P., and F. P. Hartwell.  Wiring Simplified: Based on the 2011 National Electrical Code, 43rd Edition.  Park Publishing, 2011. 
  62.  Salter, Charles.  Acoustics: Architecture, Engineering, the Environment.  William Stout Publishers, 1998. 
  63.  Schodek, Daniel L., and Martin Bechtold.  Structures, 6th Edition.  Prentice Hall, 2007. 
  64.  Scott, James G. Architectural Building Codes: A Graphic Reference.  John Wiley & Sons, 1997. 
  65.  Simmons, H. Leslie.  Olin's Construction: Principles, Materials, and Methods, 9th Edition.  John Wiley & Sons, 2011. 
  66.  Stein, Benjamin.  Building Technology: Mechanical and Electrical Systems, 2nd Edition.  John Wiley & Sons, 1997. 
  67.  Stein, Benjamin, Walter T. Grondzik, Alison G. Kwok, and John Reynolds.  Mechanical and Electrical Equipment for Buildings, 10th Edition.  John Wiley & Sons, 2005. 
  68.  Underwriters' Laboratory.  UL Fire Resistance Directory, 3 vols.  UL, 2007. 
  69.  Wakita, Osamu A., and Richard M. Linde.  Professional Practice of Architectural Working Drawings, 4th Edition.  John Wiley & Sons, 2011. 
  70.  Western Woods Products Association.  Western Woods Use Book, 4th Edition.  WWPA, 2005. 

# **INDEX**

## **A**

  * Aalto, Alvar
  * Absorptance
  * Absorption refrigeration
  * Access, building site 
    * pedestrian
    * site analysis
    * vehicular
  * Acoustic roof decking
  * Acoustic wall treatment
  * Acoustical ceilings
  * Acoustical plaster
  * Acoustics
  * Active earth pressure
  * Active solar energy systems
  * Adhesives
  * Adiabatic heating
  * Admixtures
  * Adobe construction
  * Aesthetic qualities
  * Aggregate
  * Air distribution outlets
  * Air gap
  * Air motion
  * Air temperature
  * Air-inflated pneumatic structures
  * Air-supported pneumatic structures
  * Air-water HVAC systems
  * All-air HVAC systems
  * Alloy steel
  * All-water HVAC systems
  * Alternative energy sources
  * Aluminum
  * Aluminum window frames
  * American Architectural Manufacturers Association (AAMA)
  * American Association of State Highway and Transportation Officials (AASHTO)
  * American Concrete Institute (ACI)
  * American Institute of Architects
  * American Institute of Steel Construction (AISC)
  * American National Standards Institute (ANSI)
  * American Plywood Association (APA)
  * American Society for Testing and Materials (ASTM) 
    * soil classification
    * steel reinforced concrete
    * UNIFORMAT II
  * American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE)
  * Americans with Disabilities Act (ADA) Accessibility Guidelines 
    * bathrooms
    * carpet
    * doors
    * elevators
    * kitchens
    * parking
    * pedestrian access and circulation
    * stairs
    * windows
  * Amperes
  * Angle joints
  * Angle of refraction
  * Appliance circuits
  * Aprons
  * Arches
  * Architectural Barriers Act (ABA)
  * Architecture
  * Architecture 2030
  * Architrave
  * Armored (BX) cable
  * Ashlar walls
  * Asphalt shingles
  * Atmospheric emissions
  * Attenuation
  * Attics
  * Audio frequency
  * Automatic doors
  * Awning windows

## **B**

  * Backing, carpet
  * Backing board
  * Baffles
  * Balanced doors
  * Balloon framing
  * Balusters
  * Barrel shells
  * Barrel vaults
  * Barrier wall systems
  * Base isolation
  * Base screeds
  * Base shear
  * Baseboards
  * Basecoat
  * Basements
  * Basket-handle arches
  * Bathrooms 
    * accessible fixtures
    * ceramic tile
    * layouts for
    * plumbing fixtures
    * space
  * Bathtubs
  * Batt insulation
  * Batten doors
  * Batten seams
  * Batten-and-board siding
  * Batter
  * Bay windows
  * Beam pockets
  * Beam spread
  * Beams: 
    * loads and stresses
    * spans
  * Bed joints
  * Belgian trusses
  * Bell-and-spigot pipe joints
  * Bending moment
  * Bending stress
  * Bent bars
  * Bents
  * Béton brut
  * Bevel (lap) siding
  * Bidets
  * Bifold doors
  * Bike paths
  * Bi-level switching
  * Bin walls
  * Biomass energy
  * Bird's mouth
  * Bite
  * Blinds
  * Board-and-batten siding
  * Boilers
  * Bolted connections
  * Bonnets (plenums)
  * Boots
  * Bottom bars
  * Bowstring trusses
  * Box beams
  * Box girders
  * Box stairs
  * Braced frames
  * Braced tube structures
  * Branch circuits
  * Branch vents
  * Brass
  * Brick: 
    * applying paints or coatings to
    * embodied energy in
    * types and grades of
    * weight of
  * Brick lintels
  * Brick masonry walls
  * Brick veneer walls
  * Bridging
  * Brightness
  * Brise-soleil (eggcrates)
  * British thermal units
  * Broken rangework walls
  * Brown coat
  * Brundtland, Gro Harlem
  * Buckling
  * Buffers
  * Building codes 
    * means of egress
    * windows
  * Building construction 
    * building codes
    * building systems
    * loads
    * structural equilibrium
    * structural forces
    * structural patterns
    * structural spans
    * structural system
    * structural units
    * types of
  * Building Officials and Code Administrators International, Inc. (BOCA)
  * Building site 
    * access and circulation
    * analysis of
    * context
    * daylighting
    * paving
    * plant materials
    * precipitation
    * regulatory factors
    * site description
    * site plan
    * slope protection
    * soils
    * solar radiation
    * sound
    * sustainability and green building
    * topography
    * views
    * wind
  * Building systems.  See also Electrical systems; Heating and cooling systems; Water systems 
    * enclosure system
    * factors
    * mechanical systems
    * structural system
  * Built-up beams
  * Built-up roofing systems
  * Bulbs
  * Bundled tube structures
  * Bushhammered concrete surfaces
  * Butt hinges
  * Butt joints
  * Butt-joint glazing
  * BX (armored) cable
  * Bypass sliding doors

## **C**

  * C light-gauge steel joists
  * Cabinets
  * Cable anchorages
  * Cable bracing
  * Cable structures
  * Cable television systems
  * Caisson foundations
  * Candelas
  * Candlepower distribution curve
  * Cantilever (strap) footings
  * Cantilevers
  * Cap bead/sealant
  * Cap molding
  * Caps
  * Carbon steel
  * Carpet pad
  * Carpeting
  * Carré House
  * Carriages (rough stringers)
  * Cased piles
  * Casement windows
  * Casing beads
  * Casings
  * Cast iron
  * Castellated beams
  * Catenary
  * Cavity walls
  * Ceiling cavities
  * Ceilings: 
    * acoustical
    * gypsum board
    * plaster
    * weight of materials
  * Cellular decking
  * Cementitious roof planks
  * Center of resistance
  * Ceramic mosaic tile
  * Ceramic tile
  * Chair rails
  * Channel (C) steel beams
  * Channel glass
  * Channel groove wood ceiling
  * Channel groove wood siding
  * Chilled water plants
  * Chimneys: 
    * flashing
    * HVAC systems
    * masonry
    * prefabricated fireplaces and stoves
  * Chords
  * Circuit vents
  * Circular stairs
  * Circulation 
    * pedestrian
    * site analysis
    * vehicular
    * vehicular parking
  * Cisterns
  * Clay tile
  * Climate change
  * Closed-riser stairs
  * Closers
  * Closet bends
  * Clothes washers
  * Coal
  * Coatings
  * Coefficient of utilization (CU)
  * Coiling doors
  * Collar joints
  * Collar ties
  * Collinear forces
  * Color rendering index (CRI)
  * Column footings
  * Column-cover-and-spandrel glazed curtain wall systems
  * Columns: 
    * concrete wall systems
    * loads and stresses
    * post-and-beam framing
    * steel wall systems
    * stone veneer
    * wood wall systems
  * Combed finish stucco
  * Combined footings
  * Comfort zone
  * Common bond
  * Common vents
  * Companion codes
  * Composite decking
  * Composite piles
  * Composition shingles
  * Compression gaskets
  * Compression test
  * Compressive refrigeration
  * Compressors
  * Concave joints
  * Concentrated loads
  * Concrete 
    * applying paints or coatings to
    * coefficients of linear expansion
    * embodied energy in
    * graphic symbols for
    * lightweight
    * permeability of
    * steel reinforcement
    * thermal resistance of
    * water-cement ratio
    * weight of
  * Concrete beams
  * Concrete columns
  * Concrete connections
  * Concrete floor systems 
    * beams
    * formwork and shoring
    * insulation
    * precast
    * prestressed
    * slabs
  * Concrete foundation walls
  * Concrete masonry lintels
  * Concrete masonry units (CMUs)
  * Concrete masonry walls
  * Concrete piles
  * Concrete retaining walls
  * Concrete roof slabs
  * Concrete roof systems
  * Concrete slabs: 
    * floor systems
    * wall systems
  * Concrete slabs-on-grade
  * Concrete stairs
  * Concrete structural spans
  * Concrete wall systems: 
    * columns
    * curtain walls
    * door and window openings
    * fire-resistance ratings
    * formwork
    * gypsum board
    * insulation
    * movement joints
    * precast
    * stucco
    * surfacing
    * tilt-up construction
    * walls
    * wood beam supports
  * Concurrent forces
  * Condensers
  * Conduction
  * Conduits
  * Connections 
    * adhesives
    * bolts
    * concrete
    * fastenings
    * nails
    * screws
    * steel
    * wood
  * Consolidation
  * Constant-air-volume (CAV) systems
  * Construction joints
  * Construction practices
  * Construction Specifications Institute (CSI) MasterFormat
  * Context, building in
  * Continuous beams
  * Continuous dimming
  * Continuous footings
  * Continuous vents
  * Contour lines and intervals
  * Control joints 
    * concrete retaining walls
    * concrete slabs-on-grade
    * masonry wall systems
    * plaster ceilings
    * stucco
  * Convection
  * Convenience outlets (duplex receptacles)
  * Cooling degree-days
  * Cooling load
  * Cooling systems.  See also Heating and cooling systems
  * Cooling towers
  * Copestones
  * Copper
  * Coreboard
  * Cork flooring
  * Corner beads
  * Corner blocks
  * Cornice returns
  * Cornices
  * Corporation stops
  * Correction lines
  * Correlated color temperature (CCT)
  * Corrugated metal roofing
  * Cosine law (Lambert's law)
  * Counterfort walls
  * Countertop surfaces
  * Couples
  * Couplings
  * Coursed ashlar walls
  * Coursed rubble walls
  * Courses
  * Cove moldings
  * Cover plates
  * Crawl spaces 
    * treated wood
    * vapor retarders
    * ventilation of
  * Crescent trusses
  * Cribbing
  * Crickets
  * Cripples
  * Cross (groin) vaults
  * Crushed stone
  * Curb boxes
  * Curb ramps
  * Curtain drains
  * Curtain walls
  * Cut and loop carpet
  * Cut pile carpet
  * Cutoff angle
  * Cylinder locks

## **D**

  * Dado joints
  * Dampers
  * Damping mechanisms
  * Dapping (notching)
  * Daylight harvesting
  * Daylighting
  * Dead loads
  * Deadman
  * Decibels
  * Deep foundations
  * Deflection
  * Degree-days
  * Deluge sprinkler systems
  * Depressed tendons
  * Dew point
  * Dewatering
  * Differential settlement
  * Diffused light
  * Diffusers
  * Dimension shingles
  * Dimension stone
  * Dimmers
  * Direct gain systems, passive solar design
  * Direct return heating systems
  * Directional light
  * Discharge lamps
  * Discontinuous diaphragms
  * DLH series open-web steel joists
  * Dolly Varden siding
  * Domes
  * Door hardware 
    * hinges
    * locksets
    * panic hardware and closers
  * Door knobs
  * Doors and doorframes 
    * coiling doors
    * folding doors
    * glass entrance doors
    * hardware for
    * hollow metal
    * operation of
    * overhead
    * pocket sliding doors
    * revolving doors
    * sliding glass doors
    * storefronts
    * terminology
    * thermal resistance of
    * thresholds
    * weatherstripping
    * wood
  * Doppler effect
  * Dormers
  * Double overhanging beams
  * Double trimmer rafters and joists
  * Double-acting hinges
  * Double-cable structures
  * Double-hung windows
  * Double-skin facades
  * Dovetail joints
  * Downspouts
  * Drainage 
    * foundation walls
    * paving
    * retaining walls
    * roof systems
    * roofing
    * sanitary drainage systems
    * site analysis
  * Drainfields
  * Draped tendons
  * Dripstones
  * Drop arches
  * Drop elbows
  * Drop panels
  * Drop siding
  * Dry glazing
  * Dry return heating systems
  * Dry stone walls
  * Dry wells
  * Dry-pipe sprinkler systems
  * Dual-duct HVAC systems
  * Duplex receptacles (convenience outlets)
  * Dynamic loads

## **E**

  * Earthquake loads
  * Easements
  * Eave flashing
  * Eaves
  * Echoes
  * Economic considerations
  * Edge blocks
  * Edge clearance
  * Edge joints
  * Effective length factor
  * Effective temperature
  * Efflorescence
  * Eggcrates (brise-soleil)
  * Elasticity
  * Elastomeric membrane roofing
  * Elbows
  * Electric elevators
  * Electric heating
  * Electrical systems 
    * access flooring
    * bathroom
    * circuits
    * heating and cooling
    * kitchen
    * outlets
    * power
    * service
    * wiring
  * Electrodes (grounding rods)
  * Elevators
  * Elliptical reflectors
  * Embodied energy
  * Enclosure system
  * End joints
  * End-bearing piles
  * Energy consumption and conservation: 
    * building in context
    * heating and cooling systems
    * LEED Green Building Rating System
    * passive solar design
    * by sector
    * 2030 Challenge
  * Energy efficiency ratings
  * Energy-recovery ventilation
  * Engineered flooring
  * English bond
  * Enthalpy
  * Escalators
  * Escutcheons
  * Evaporation
  * Evaporative cooling
  * Evaporators
  * Excavation support systems
  * Exits
  * Expansion bolts
  * Expansion joints 
    * concrete retaining walls
    * concrete slabs-on-grade
    * exterior insulation and finish systems
    * flashing
    * foundation walls
    * glass block
    * masonry wall systems
    * sealants
  * Explosive rivets
  * Exposed aggregate concrete finishes
  * Extended plenum heating systems
  * Extensive vegetative roofing
  * Exterior insulation and finish systems (EIFS)
  * Exterior Insulation Manufacturers Association (EIMA)
  * Extrados

## **F**

  * Face clearance
  * Face glazing
  * Face putty
  * Fascia
  * Fastenings
  * Federal Fair Housing Act (FFHA) of 1988
  * Fiber forms
  * Fiber optics
  * Fiber saturation point
  * Fiberboard sheathing
  * Fiberglass shingles
  * Finish coat
  * Finish work 
    * acoustical ceilings
    * bathrooms
    * flooring
    * gypsum board
    * plaster
    * plastic laminate
    * wood
  * Fink trusses
  * Fin-tube convectors
  * Fire protection: 
    * building codes
    * curtain walls
    * doors
    * exits
    * fire-resistance ratings
    * sprinklers
    * steel floor systems
    * steel wall systems
    * types of construction
    * wood joists
    * wood roof systems
    * wood shingles and shakes
  * Fire pumps
  * Fireboxes
  * Fireplaces
  * Fixed (rigid) joints
  * Fixed frames
  * Fixed windows
  * Fixed-end beams
  * Fixture runout
  * Fixture shutoff valves
  * Flagstone
  * Flashing
  * Flat Glass Marketing Association (FGMA)
  * Flat roof assemblies 
    * drainage
    * flashing
    * loads
    * moisture and thermal protection
    * movement joints
    * precipitation
    * roofing
    * slopes
    * wood rafter framing
  * Flat trusses
  * Flemish bond
  * Flemish cross bond
  * Flemish diagonal bond
  * Flexible pavements
  * Flitch beams
  * Float finish stucco
  * Float glass
  * Floating foundations
  * Floating wood flooring
  * Flocked carpet
  * Flood level
  * Floor cavity
  * Floor hinges
  * Floor systems 
    * concrete
    * fire-resistance ratings
    * insulation
    * loads
    * steel
    * thermal resistance of materials
    * weight of materials
    * wood
  * Flooring: 
    * access flooring systems
    * carpeting
    * ceramic tile
    * kitchen
    * resilient
    * stone
    * terrazzo
    * weight of materials
    * wood
  * Flues
  * Fluorescent lamps
  * Flush doors
  * Flush glazing
  * Flush joints
  * Flutter
  * Flying forms
  * Foamed-in-place insulation
  * Focusing
  * Foil-backed gypsum board
  * Folded plate structures
  * Folding doors
  * Foot-candles
  * Foot-lamberts
  * Forced-air heating
  * Form decking
  * Form ties
  * Formica
  * Formwork: 
    * concrete floor systems
    * concrete wall systems
  * Foundation systems 
    * deep foundations
    * excavation support systems
    * loads
    * settlement
    * shallow foundations
    * types of
    * underpinning
  * Foundation walls: 
    * basements
    * concrete
    * concrete masonry
    * crawl spaces
    * drainage and waterproofing
    * repairing and extending
    * treated wood
    * wood beams
    * wood joists
  * Four-pipe HVAC systems
  * Four-way switches
  * Framed tube structures
  * Frameless doors
  * Frames
  * Free-body diagrams
  * French drains
  * Fresnel lenses
  * Friction piles
  * Frictional damping
  * Frieze (twist) carpet
  * Frieze boards
  * Frostline
  * Full-mortise hinges
  * Full-surface hinges
  * Funicular shapes
  * Furniture dimensions
  * Furring
  * Fusion-bonded carpet

## **G**

  * Gabions
  * Gable dormers
  * Gable roofs
  * Gables
  * Galvanic action
  * Galvanic series
  * Galvanized iron
  * Gambrel roofs
  * Garage ramps
  * Garages
  * Garden-wall bond
  * Gas: 
    * heating and cooling systems
    * kitchen appliances
  * Gatherings
  * Gauge, carpeting
  * Gauging plaster
  * General purpose circuits
  * Geodesic domes
  * Geothermal energy
  * Girder supports
  * Glare
  * Glass.  See also Doors and doorframes; Windows 
    * embodied energy in
    * glass products
    * graphic symbols for
    * heat-absorbing
    * permeability of
    * thermal resistance of
    * weight of
  * Glass block
  * Glass doors
  * Glass mullion system
  * Glass-edge units
  * Glazed curtain walls
  * Glazed wall tile
  * Glazier's points
  * Glazing
  * Glazing bead/stop
  * Glazing compound
  * Glazing systems
  * Glazing tape
  * Global warming
  * Glue-laminated timber
  * Glueless laminated wood flooring
  * Gothic arches
  * Grab bars
  * Grade beams
  * Gravity downfeed water systems
  * Gravity walls
  * Graywater
  * Green (vegetated) roofing
  * Green building 
    * defined
    * LEED Green Building Rating System
    * 2030 Challenge
  * Greenhouses
  * Grids
  * Grills
  * Groin (cross) vaults
  * Ground fault interrupters (GFIs)
  * Ground pressure
  * Grounding rods (electrodes)
  * Grouted masonry walls
  * Guardrails
  * Guide meridians
  * Gunnable sealants
  * Gutters
  * Guy cables
  * Gypsum: 
    * applying paints or coatings to
    * embodied energy in
    * permeability of
    * thermal resistance of
    * weight of
  * Gypsum board
  * Gypsum lath
  * Gypsum sheathing

## **H**

  * Half-mortise hinges
  * Half-surface hinges
  * Half-turn stairs
  * Handrails
  * Hard finish
  * Head joints
  * Headers
  * Heads
  * Heat gain
  * Heat loss
  * Heat pumps
  * Heating and cooling systems 
    * access flooring systems
    * active solar energy systems
    * air distribution outlets
    * alternative energy sources
    * bathroom
    * comfort zone
    * concrete slabs-on-grade
    * cooling systems
    * electric heating
    * forced-air heating
    * heating and cooling loads
    * hot-water heating
    * HVAC systems
    * kitchen
    * psychrometric charts
    * radiant heating
    * thermal comfort
  * Heating degree-days
  * Heating load
  * Heel bead
  * Heel joints
  * Heels
  * High-intensity discharge (HID) lamps
  * High-rise structures
  * Hi-lo loop carpet
  * Hinged frames
  * Hinges
  * Hip
  * Hip jacks
  * Hip roofs
  * Holding ponds
  * Hollow core wood doors
  * Hollow metal doors and doorframes
  * Hooks
  * Hoop forces
  * Hopper windows
  * Horizontal (longitudinal) shearing stress
  * Horizontal board siding
  * Horizontal diaphragms
  * Hose bibbs
  * Hot-water (hydronic) heating
  * Howe trusses
  * H-piles
  * Human dimensions
  * Hydraulic elevators
  * Hydrogen
  * Hydronic (hot-water) heating
  * Hydropower
  * Hyperbolic paraboloids
  * Hysteresis damping

## **I**

  * I-beam (S) steel beams
  * Igneous rock
  * I-joists, prefabricated wood
  * Illumination
  * Imbrex
  * Impact loads
  * Impact noise
  * Incandescent lamps
  * Increasers
  * Indirect gain systems, passive solar design
  * Individual circuits
  * Indoor environmental quality
  * Infill panels (spandrel glass)
  * Innovation in sustainable design
  * Insulating glass
  * Insulation 
    * exterior insulation and finish systems
    * floors
    * graphic symbols for
    * materials for
    * moisture control
    * roofs
    * thermal
    * thermal resistance
    * walls
    * weight of materials
  * Intensive vegetative roofing
  * Interlocking (overlapping) joints
  * Internal damping
  * International Building Code (IBC)
  * International Code Council (ICC)
  * International Conference of Building Officials (ICBO)
  * International Council for Research and Innovation in Building and Construction
  * International Energy Conservation Code (IECC)
  * International Existing Building Code (IEBC)
  * International Fire Code (IFC)
  * International Mechanical Code (IMC)
  * International Plumbing Code (IPC)
  * International Residential Code (IRC)
  * Intrados
  * Inverse square law
  * Invisible hinges
  * Isocharts
  * Isolated footings
  * Isolated gain systems, passive solar design
  * Isolation joints
  * Isolux line

## **J**

  * Jack arches
  * Jack rafters
  * Jalousie windows
  * Jambs
  * Joints 
    * concrete retaining walls
    * concrete slabs-on-grade
    * foundation walls
    * frames
    * masonry
    * plaster
    * sealants
    * seismic
    * stucco
    * trusses
    * wood finish work
  * Joist bands
  * Junction boxes

## **K**

  * K series open-web steel joists
  * Keene's cement
  * Kern area
  * Keystones
  * Kick plates
  * Kitchens
  * Knee bracing
  * Knee walls
  * Knitted carpet

## **L**

  * Ladders
  * Lagging
  * Lamberts
  * Lambert's law (cosine law)
  * Laminated veneer lumber (LVL)
  * Lamp lumen depreciation
  * Lancet arches
  * Landings
  * Lap (bevel) siding
  * Lap joints
  * Lateral stability 
    * concrete columns
    * foundation systems
    * high-rise structures
    * masonry wall systems
    * precast concrete wall systems
    * steel floor systems
  * Lath
  * Lattice domes
  * Latticed truss tube structures
  * Lavatories
  * Law of reflection
  * Lead
  * Leaders
  * LEED (Leadership in Energy and Environmental Design) Green Building Rating System
  * Level loop carpet
  * Lever handles
  * LH series open-web steel joists
  * Life Safety Code (NFPA-101)
  * Life-cycle assessment
  * Lift-slab construction
  * Light loss factor
  * Light shelves
  * Light-emitting diodes (LEDs)
  * Light-gauge steel joist floor systems
  * Light-gauge steel wall systems
  * Lighting 
    * bathroom
    * color and
    * kitchen
    * luminaires
    * sources of
    * vision and
  * Limited use/limited access (LU/LA) elevators
  * Linear connectors
  * Linoleum flooring
  * Lintels
  * Live loads
  * Load balancing
  * Loads 
    * beams
    * columns
    * curtain walls
    * dead
    * earthquake
    * floor systems
    * foundation systems
    * heating and cooling
    * live
    * masonry wall systems
    * pile foundations
    * plate structures
    * post-and-beam framing
    * roof systems
    * static
    * steel floor systems
    * trusses
    * walls
    * wind
  * Locksets
  * Long-and-short work
  * Longitudinal (horizontal) shearing stress
  * Lookout rafters
  * Loop pile carpet
  * Loop vents
  * Loose-fill insulation
  * Louvers
  * Low-voltage circuits
  * L-type cantilevered walls
  * Lumber.  See also Wood
  * Lumen method (zonal cavity method)
  * Lumens
  * Luminaire dirt depreciation
  * Luminaires
  * Luminance
  * Luminous flux
  * Luminous intensity
  * Lux

## **M**

  * Manifolds
  * Manual of Steel Construction (AISC)
  * Masonry 
    * applying paints or coatings to
    * coefficients of linear expansion
    * graphic symbols for
    * permeability of
    * plaster over
    * thermal resistance of
  * Masonry arches
  * Masonry chimneys
  * Masonry wall systems: 
    * adobe construction
    * arches
    * bonding
    * columns and pilasters
    * concrete slabs-on-grade
    * expansion and control joints
    * fire-resistance ratings
    * flashing
    * foundation walls
    * glass block
    * gypsum board
    * insulation
    * lintels
    * metal doorframes
    * movement joints
    * rammed-earth construction
    * reinforced
    * retaining walls
    * stone
    * structural clay tile
    * stucco
    * unreinforced
    * veneer
    * wall sections
    * walls
    * windows
    * wood beam supports
  * Masts
  * Mat (raft) foundations
  * Materials 
    * coefficients of linear expansion
    * concrete
    * conservation of
    * fastenings
    * glass
    * Graphic Symbols for
    * LEED Green Building Rating System
    * life-cycle assessment
    * masonry
    * nonferrous metals
    * paints and coatings
    * paving
    * permeability of
    * plastics
    * properties of
    * steel
    * stone
    * thermal resistance of
    * weights of
    * wood
  * Mazria, Edward
  * Mean radiant temperature (MRT)
  * Means of egress
  * Mechanical and electrical systems 
    * electrical
    * heating and cooling
    * lighting
    * water and waste
  * Membrane roofing
  * Membrane structures
  * Meridians
  * Meridional forces
  * Metal cladding
  * Metal decking
  * Metal doors and doorframes
  * Metal lath
  * Metal roofing
  * Metal windows
  * Metals.  See also Steel: 
    * graphic symbols for
    * nonferrous
    * weight of
  * Metamorphic rock
  * Metes-and-bounds surveys
  * Metric conversion factors
  * Microclimate
  * Micropiles
  * Mineral-insulated cable
  * Mission (Spanish) tiles
  * Miter joints
  * Model codes
  * Modular block roofing systems
  * Moisture and thermal protection 
    * expansion joints
    * flashing
    * insulation
    * moisture control
    * roofing
    * walls
  * Molded (plain) spline wood ceiling
  * Molded (shaped) joints
  * Molding plaster
  * Moment
  * Moment connections
  * Moment of inertia
  * Mortar
  * Mortise locks
  * Mortise splices
  * Mortise-and-tenon joints
  * Movement joints
  * Moving sidewalks
  * Mullions
  * Multilevel loop carpet
  * Multi-level switching
  * Muntins

## **N**

  * Nails
  * National Electric Code (NFPA-70)
  * National Evaluation Service, Inc. (NES)
  * National Fire Protection Association (NFPA)
  * National Kitchen Cabinet Association (NKCA)
  * National Research Board (NRB)
  * National Wood Window and Door Association (NWWDA)
  * Natural gas
  * Neat plaster
  * Needlepunched carpet
  * Nestable light-gauge steel joists
  * Neutral axis
  * Newton's laws of motion
  * Nipples
  * Noise reduction
  * Nonconcurrent forces
  * Nonferrous metals
  * Nonmetallic sheathed (Romex) cable
  * Nonrecoverable light loss factor (NRLLF)
  * Nosings
  * Notching (dapping)
  * Nuclear energy

## **O**

  * Occupancy classifications
  * Occupancy lighting controls
  * Occupancy limits
  * Occupancy loads
  * Occupancy separations
  * Ocean Thermal Energy Conversion (OTEC)
  * Ohms
  * Oil
  * Olive knuckle hinges
  * One-pipe heating systems
  * One-sheet hyperboloids
  * One-way concrete slabs
  * One-way joist slabs
  * One-way spanning systems
  * One-way steel beam floor systems
  * Open-riser stairs
  * Open-web steel joists
  * Oriented strandboard (OSB)
  * Our Common Future (UNCED)
  * Outdoor receptacles
  * Overhanging beams
  * Overhead doors
  * Overlapping (interlocking) joints
  * Overturning moment

## **P**

  * Packaged HVAC systems
  * Paints
  * Panel point
  * Panel subfloors
  * Panelboards
  * Panels, truss
  * Panes
  * Panic hardware
  * Pans
  * Pantiles
  * Parabolic reflectors
  * Parallel strand lumber (PSL)
  * Parallelogram law
  * Parapets
  * Parking
  * Parliament hinges
  * Particleboard
  * Parting compound
  * Passive earth pressure
  * Passive solar design
  * Patterns: 
    * exposed wood ceilings
    * masonry bonding
    * paving
    * plywood veneer
    * structural
  * Paver tiles
  * Paving
  * Pedestal piles
  * Pedestrian access and circulation
  * Perforated shell tube structures
  * Performance requirements
  * Perimeter heating systems
  * Perms
  * Photovoltaic (PV) technology
  * Piano hinges
  * Picture molding
  * Pile
  * Pile eccentricity
  * Pile foundations
  * Pinned joints
  * Pipe piles
  * Pisé de terre (rammed-earth) construction
  * Pitch
  * Pitched roofs
  * Pivoted doors
  * Pivoting windows
  * Plain (molded) spline wood ceiling
  * Plank flooring
  * Plank-and-beam framing
  * Planned Unit Development
  * Plant materials 
    * microclimate
    * site analysis
    * slope protection
    * surface drainage
    * trees
  * Plaster 
    * applying paints or coatings to
    * ceilings
    * coefficients of linear expansion
    * details
    * graphic symbols for
    * lath and accessories
    * over masonry
    * partition systems
    * permeability of
    * thermal resistance of
    * weight of
  * Plastics
  * Plate girders
  * Plate glass
  * Plate rails
  * Plate structures
  * Platform framing
  * Plenums (bonnets)
  * Plinth blocks
  * Plinths
  * Plugs
  * Plumbing: 
    * bathroom
    * kitchen
  * Plumbing fixtures
  * Plush carpet
  * Plywood 
    * siding
    * veneer
  * Pneumatic structures
  * Pocket sliding doors
  * Point connectors
  * Pole foundations
  * Polygon method
  * Portland cement
  * Post-and-beam framing: 
    * floor systems
    * roof systems
    * wall systems
  * Posttensioning
  * Pratt trusses
  * Preaction sprinkler systems
  * Precast concrete connections
  * Precast concrete floor systems
  * Precast concrete lintels
  * Precast concrete roof systems
  * Precast concrete wall systems: 
    * columns
    * connections
    * wall panels
    * walls
  * Precipitation.  See also Moisture and thermal protection 
    * rain loads
    * roof systems
    * site drainage
    * snow loads
  * Prefinished gypsum board
  * Preheaters
  * Pressure-equalized design
  * Prestressed concrete floor systems
  * Pretensioning
  * Principal meridians
  * Prismatic lenses
  * Private roadways
  * Private wells
  * Professional and trade associations
  * Propane gas
  * Protected membrane roofing
  * Psychrometric charts
  * Public water supply
  * Pull handles
  * Purlins
  * Push plates
  * Putty

## **Q**

  * Quarry tiles
  * Quarter-turn stairs
  * Quartz heaters
  * Quoins

## **R**

  * Radiant heating
  * Radiation
  * Radiators
  * Radius of gyration
  * Raft (mat) foundations
  * Rail and stile doors
  * Rails
  * Rain loads
  * Rainscreen wall systems
  * Raised-chord trusses
  * Rake
  * Raked joints
  * Rammed-earth (pisé de terre) construction
  * Ramps
  * Random ashlar walls
  * Random rubble walls
  * Range lines
  * Ranges, kitchen
  * Ranges, site description
  * Rated panel sheathing
  * Ready-mixed plaster
  * Receptacles
  * Recoverable light loss factors (RLLFs)
  * Reducers
  * Reentrant corners
  * Reflectance
  * Reflective insulation
  * Reflectors
  * Refrigerant
  * Refrigerators
  * Regional building forms and orientations: 
    * adobe and rammed-earth construction
    * solar radiation and
  * Registers
  * Regulatory factors
  * Reinforced concrete.  See Concrete
  * Relative humidity (RH)
  * Relief joints
  * Relief vents
  * Residential drives
  * Resilient flooring
  * Resisting moment
  * Resonance
  * Restoring moment
  * Restrictive covenants
  * Retaining walls
  * Reverberation
  * Reverse return heating systems
  * Revolving doors
  * Ribbed loop carpet
  * Ridge beams
  * Ridge boards
  * Ridge vents
  * Ridges
  * Rights-of-way
  * Rigid (fixed) joints
  * Rigid arches
  * Rigid foam insulation
  * Rigid foam plastic sheathing
  * Rigid frames
  * Rigid pavements
  * Rim joists (headers)
  * Riprap
  * Rise
  * Risers
  * Rivets
  * Rock caissons
  * Rock-dash finish stucco
  * Roll seams
  * Roller joints
  * Roman arches
  * Romex (nonmetallic sheathed) cable
  * Roof ponds
  * Roof systems.  See also Roofing 
    * cementitious roof planks
    * concrete
    * fire-resistance ratings
    * insulation
    * metal roof decking
    * precipitation
    * rafter framing styles
    * roof slopes
    * steel
    * terminology
    * thermal resistance of materials
    * ventilation of
    * weight of materials
    * wind pressure
    * wood
  * Roofing 
    * built-up roofing systems
    * composition shingles
    * corrugated metal
    * drainage
    * flat roof assemblies
    * moisture and thermal protection
    * sheet metal
    * single-ply roofing systems
    * slate shingles
    * tile
    * underlayment for shingles
    * vegetated
    * wood shakes
    * wood shingles
  * Room cavity
  * Room cavity ratio
  * Room surface dirt depreciation
  * Roses
  * Rough openings
  * Rough stringers (carriages)
  * Rowlocks
  * Rubber flooring
  * Rubble
  * Ruled surfaces
  * Running bond
  * Rustication
  * R-value

## **S**

  * Saddle surfaces
  * Saddles
  * Sand filters
  * Sanitary drainage systems
  * Sanitary tees
  * Sashes
  * Saxony plush carpet
  * Schwedler domes
  * Scissors trusses
  * Scratch coat
  * Screens
  * Screws
  * Seated connections
  * Section modulus
  * Sections
  * Sedimentary rock
  * Seepage pits
  * Segmental arches
  * Seismic joints
  * Semi-rigid connections
  * Septic tanks
  * Service conductors
  * Service drops
  * Service pipes
  * Setting blocks
  * Settlement
  * Settlement loads
  * Sewage disposal systems
  * Shading devices
  * Shag carpet
  * Shallow foundations 
    * column footings
    * concrete slabs-on-grade
    * foundation walls
    * pole foundations
    * on sloping ground
    * spread footings
  * Shaped (molded) joints
  * She bolts
  * Shear connections
  * Shear plates
  * Shear walls
  * Sheathing: 
    * wood roof systems
    * wood stud walls
    * wood subflooring
  * Shed dormers
  * Shed roofs
  * Sheet glass
  * Sheet metal roofing
  * Sheet piling
  * Shell structures
  * Shielding angle
  * Shingle tiles
  * Shiplap siding
  * Ship's ladders
  * Shoring
  * Showers
  * Siamese pipe fittings
  * Sidewalks
  * Siding: 
    * alternative
    * applying
    * horizontal board
    * plywood
    * thermal resistance of
    * vertical board
    * wood shingle
  * Sills
  * Single-curvature cable structures
  * Single-duct HVAC systems
  * Single-hung windows
  * Single-ply roofing systems
  * Sinks
  * Site analysis
  * Site description
  * Site drainage
  * Site plan
  * Skewbacks
  * Skylights
  * Slate shingles
  * Slenderness ratio of columns
  * Sliding doors
  * Sliding windows
  * Slopes: 
    * drainage
    * foundation systems
    * pole foundations
    * protecting
    * retaining walls
    * roof systems
    * setback requirement exceptions
    * skylights
    * soil mechanics and
    * topography
  * Slump test
  * Slurry walls
  * Smoke chambers
  * Smoke shelves
  * Snap ties
  * Snow loads
  * Socketed caissons
  * Soffits
  * Soft (weak) stories
  * Soil stacks
  * Soils: 
    * classes of
    * excavation support systems
    * graphic symbols for
    * ground pressure
    * mechanics of
    * retaining walls
    * site analysis
    * slope protection
    * soil profiles
    * trees as stabilizer for
    * weight of
  * Solar energy 
    * active solar energy systems
    * passive solar design
    * photovoltaic technology
    * water-heating systems
  * Solar radiation.  See also Moisture and thermal protection 
    * building in context
    * curtain walls
    * daylighting
    * glass products and
    * insulating glass
    * microclimate
    * reflection and absorption
    * regional building forms and orientations
    * representative solar angles
    * shade trees
    * shading devices
    * site analysis
    * solar constant
    * solar path diagram
  * Solar shading
  * Solariums
  * Soldier piles/beams
  * Soldiers
  * Sole plates
  * Solid core wood doors
  * Solid sawn lumber
  * Sonotube
  * Sound: 
    * acoustic roof decking
    * acoustics
    * building site
    * controlling
    * site analysis
    * trees and
  * Sound transmission class (STC)
  * Southern Building Code Conference (SBCC)
  * Space frames
  * Spaced beams
  * Spacer-edge units
  * Spandrel glass (infill panels)
  * Spandrels
  * Spanish (mission) tiles
  * Special construction 
    * bathrooms
    * elevators
    * escalators
    * fireplaces
    * kitchens
    * ladders
    * stairs
  * Spiked grid connectors
  * Spiral reinforcement
  * Spiral stairs
  * Split-packaged HVAC systems
  * Split-ring connectors
  * Split-wired receptacles
  * Spread footings
  * Spring
  * Spring hinges
  * Sprinklers
  * Squared rubble walls
  * Stack bond
  * Stack flashing
  * Stacks
  * Stains
  * Stairs 
    * concrete
    * design of
    * exterior
    * plans for
    * requirements for
    * riser and tread dimensions
    * slab steps
    * spiral
    * steel
    * terrazzo
    * wood
  * Standing seams
  * Standpipes
  * Static loads
  * Steel 
    * coefficients of linear expansion
    * embodied energy in
    * fire-resistance ratings
    * reinforced concrete
    * thermal resistance of
    * weight of
  * Steel angle lintels
  * Steel beams
  * Steel bearing plates
  * Steel columns
  * Steel floor systems 
    * beams
    * connections
    * framing
    * insulation
    * light-gauge joists
    * metal decking
    * open-web joists
  * Steel joists: 
    * light-gauge
    * open-web
    * span ranges
  * Steel roof systems: 
    * framing
    * insulation
    * open-web joists
    * rigid frames
    * space frames
    * trusses
  * Steel splice connectors
  * Steel stairs
  * Steel structural spans
  * Steel wall systems 
    * columns
    * curtain walls
    * framing
    * gypsum board
    * insulation
    * light-gauge studs
    * metal doorframes
    * windows
  * Steel window frames
  * Steel Window Institute (SWI)
  * Step ladders
  * Stepped footings
  * Steradians
  * Stick glazed curtain wall system
  * Stiffener angles
  * Stiffener plates
  * Stiffness
  * Stiles
  * Stipple-troweled finish stucco
  * Stirrups
  * Stone 
    * graphic symbols for
    * weight of
  * Stone flooring
  * Stone masonry wall systems
  * Stops
  * Storefronts
  * Straight-run stairs
  * Strain
  * Strap (cantilever) footings
  * Strap bridging
  * Stress
  * Stressed-skin panels
  * Stretchers
  * Striated wood ceiling
  * Stringcourses
  * Strip flooring
  * Strip footings
  * Struck joints
  * Structural clay tile
  * Structural equilibrium
  * Structural facing tile
  * Structural forces
  * Structural gaskets
  * Structural patterns
  * Structural spans
  * Structural system 
    * arches and vaults
    * beams
    * cable structures
    * columns
    * domes
    * frames and walls
    * high-rise structures
    * joints and connections
    * lateral stability
    * membrane structures
    * plate structures
    * shell structures
    * trusses
  * Structural tubing
  * Structural units
  * Stucco
  * Subflooring
  * Subsills
  * Subsurface drainage
  * Sump pumps
  * Sunrooms
  * Sunspaces
  * Surcharge
  * Surface connectors
  * Surface drainage
  * Surface sliding doors
  * Survey plats
  * Suspended spans
  * Suspension structures
  * Sustainability 
    * building in context
    * building systems and
    * defined
    * framework for sustainable development
    * green building
    * LEED Green Building Rating System
    * 2030 Challenge
  * Swales
  * Sway bracing
  * Swinging doors
  * Switches

## **T**

  * Tees
  * Tegula
  * Telephone systems
  * Template hinges
  * Tension rings
  * Tent structures
  * Terminal reheat systems
  * Terrazzo flooring
  * Thermal comfort
  * Thermal protection.  See Moisture and thermal protection
  * Thermal stresses
  * Thermoplastic membrane roofing
  * Thickened edge slabs
  * Thickset process
  * Thin-coat (veneer) plaster
  * Thinset process
  * Three-coat plaster
  * Three-hinged frames
  * Three-way switches
  * Threshold of hearing
  * Threshold of pain
  * Thresholds
  * Throats
  * Tidal power
  * Tiebacks
  * Tile roofing
  * Tilt-up construction
  * Toggle bolts
  * Toggle switches
  * Toilet stalls
  * Tongue-and-groove siding
  * Tons of refrigeration
  * Tooled joints
  * Top bars
  * Topography
  * Torsional irregularity
  * Townships
  * Transformers
  * Translational surfaces
  * Transmission loss (TL)
  * Transmittance
  * Transverse shear
  * Traps
  * Treads
  * Trees
  * Triple steel beam floor systems
  * Troweled joints
  * Truss bars
  * Truss rods
  * Trussed beams
  * Trussed rafter roof systems
  * Trussed tube structures
  * Trusses 
    * prefabricated wood
    * steel roof systems
    * wood roof systems
  * T-type cantilevered walls
  * Tube-in-tube structures
  * Tudor arches
  * Tufted carpet
  * Tuned mass dampers
  * Tungsten-halogen lamps
  * 2030 Challenge
  * Twist (frieze) carpet
  * Two-coat plaster
  * 2-4-1 plywood
  * Two-pipe heating systems
  * Two-pipe HVAC systems
  * Two-way flat plates
  * Two-way flat slabs
  * Two-way slab and beam systems
  * Two-way spanning systems
  * Two-way steel beam floor systems
  * Two-way waffle slabs
  * Type-X gypsum board

## **U**

  * Uncased piles
  * Underlayment, subfloor
  * Underlayment for shingles
  * Underpinning
  * Underwriters' Laboratories (UL)
  * UNIFORMAT II
  * Uniformly distributed loads
  * Unions
  * Unit and integral locks
  * Unit glazed curtain wall systems
  * Unit-and-mullion glazed curtain wall system
  * United Nations World Commission on Environment and Development
  * Unreinforced masonry wall systems
  * Upfeed water systems
  * Urinals
  * U.S. Access Board
  * U.S. Energy Information Administration
  * U.S. Green Building Council (USGBC)
  * U.S. Occupational Health and Safety Act (OSHA)

## **V**

  * Valley
  * Valley jacks
  * Valley rafters
  * Vapor retarders
  * Variable-air-volume (VAV) systems
  * Varnishes
  * Vaults
  * Vegetated (green) roofing
  * Vehicular access and circulation
  * Veneer (thin-coat) plaster
  * Veneers: 
    * brick
    * grades of
    * masonry
    * plywood
    * stone
  * Vent stacks
  * Ventilation 
    * bathroom
    * kitchen
    * sanitary drainage systems
  * Venturi tees
  * Vertical board siding
  * Vertical ladders
  * Vertical shearing stress
  * Vertical transportation systems
  * V-groove wood ceiling
  * Vierendeel trusses
  * Views, building site
  * Vinyl flooring
  * Vinyl Siding Institute (VSI)
  * Viscous damping
  * V-joints
  * Volatile organic compounds (VOC)
  * Volts
  * Voussoirs

## **W**

  * Waferboard
  * Wainscot
  * Wall systems 
    * balloon framing
    * concrete
    * curtain walls
    * fire-resistance ratings
    * flashing
    * insulation
    * loadbearing walls
    * masonry
    * masonry veneer
    * metal cladding
    * platform framing
    * precast concrete panels
    * rainscreen wall systems
    * siding
    * steel
    * stone veneer
    * structural frames
    * stucco
    * thermal resistance of materials
    * weight of materials
    * wood
  * Wallboard
  * Warren trusses
  * Washers
  * Waste stacks
  * Water.  See also Moisture and thermal protection: 
    * building in context
    * curtain walls
    * dewatering
    * efficiency
    * foundation walls
    * microclimate
    * precipitation
    * rain loads
    * roof drainage
    * roof systems
    * site analysis
    * site drainage
    * snow loads
    * water pressure
    * water table
    * weight of
  * Water closets
  * Water hammer
  * Water heaters
  * Water mains
  * Water pressure
  * Water softeners
  * Water systems 
    * fire protection systems
    * plumbing fixtures
    * sanitary drainage systems
    * sewage disposal systems
    * water supply systems
  * Water table
  * Water-resistant gypsum board
  * Watt-hour meters
  * Watts
  * Wave energy
  * Weak (soft) stories
  * Weathered joints
  * Weatherstops
  * Weatherstripping
  * Web
  * Welded steel connections
  * Wells
  * Wet glazing
  * Wet vents
  * Wet-pipe sprinkler systems
  * White coat
  * White noise
  * Whole-house ventilation
  * Wide-flange (W) steel
  * Wind: 
    * building in context
    * building site
    * cable structures
    * design wind pressure
    * flutter
    * microclimate
    * roof systems
    * site analysis
    * trees as windbreak
  * Wind loads
  * Wind power
  * Windbreaks
  * Winding stairs
  * Windows 
    * double-skin facades
    * elements of
    * glazed curtain walls
    * glazing systems
    * insulating glass
    * metal
    * operation of
    * skylights
    * sunspaces
    * thermal resistance of
    * views
    * wood
  * Windscreens
  * Wood 
    * applying paints or coatings to
    * coefficients of linear expansion
    * defects in
    * embodied energy in
    * graphic symbols for
    * lumber classifications
    * panel products
    * permeability of
    * preservative treatments
    * structural spans
    * thermal resistance of
    * weight of
  * Wood beams
  * Wood columns
  * Wood decking
  * Wood doors and doorframes
  * Wood finish work
  * Wood floor systems 
    * beams
    * decking
    * insulation
    * joists
    * plank-and-beam framing
    * post-beam connections
    * prefabricated joists and trusses
    * subflooring
  * Wood flooring
  * Wood joists
  * Wood piles
  * Wood plank-and-beam framing
  * Wood post column footings
  * Wood post-and-beam framing: 
    * floor systems
    * roof systems
    * wall systems
  * Wood roof systems 
    * insulation
    * plank-and-beam framing
    * post-beam connections
    * rafters
    * sheathing
    * trussed rafters
    * trusses
  * Wood shakes
  * Wood shingles
  * Wood siding
  * Wood stairs
  * Wood trussed rafters
  * Wood trusses
  * Wood wall systems 
    * columns
    * gypsum board
    * insulation
    * metal doorframes
    * post-and-beam framing
    * post-beam connections
    * retaining walls
    * stud framing
    * stud wall sheathing
    * windows
  * Wood windows
  * Woodburning stoves
  * Wood-fibered plaster
  * Work plane
  * Woven carpet
  * Wrought iron
  * Wyes
  * Wythes

## **Z**

  * Zero-force members
  * Zonal cavity method (lumen method)
  * Zoning ordinances

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