# Presentation: 671260

## ANSI/ASHRAE/IESNA Standard 90.1

**ANSI/ASHRAE/IESNA Standard 90.1**

**Produced by the Pacific Northwest National Laboratory**

**U.S. Department of Energy  ****Building Energy Codes Program**

## Copyright, etc.

- Please be aware that all actual text and graphics from the 90.1 Standard are copyrighted by ASHRAE
- Text used verbatim from the Standard in these materials is marked in quotes
- 2001 NOTE: Red/underlined items in these materials illustrate 90.1-2001 requirements

## DOE’s Interest in 90.1

- Per the requirement in the Energy Policy Act of 1992
- DOE has “determined” that Standard 90.1-1999 saves energy over Standard 90.1-1989
- States now have two years to notify DOE that they have adopted a commercial energy code that meets or exceeds Standard 90.1-1999

## DOE’s Determination

- For more information on the determination
- _[www.energycodes.gov](http://www.energycodes.gov/)_
- DOE estimates that, overall, Standard 90.1-1999 saves about 5% over Standard 90.1-1989
- Savings are primarily associated with lighting and some mechanical equipment

## Why is Standard 90.1 important?

- It replaces ANSI/ASHRAE/IESNA Standard 90.1-1989 and the codified version of Standard 90.1-1989 (the gray book)
- It is the reference standard for Chapter 7 of the 2001 IECC
- It is also the commercial energy reference in NFPA’s family of codes

## How has it changed since 90.1-1989?

- Written in mandatory, enforceable language
- Contains true prescriptive path for envelope
- Mechanical and envelope sections heavily dependent on economic analysis
- Lighting section heavily dependent on lighting quality considerations
- Pays considerable more attention to existing buildings

## How has it changed?

- Does not include lighting tradeoff software (LTGSTD)
- Does include a simplified mechanical systems approach for “simple” buildings
- Does include separate envelope requirements for non-residential, residential, and semi-heated spaces
- Is accompanied by ASHRAE Guideline 18 (ways to go beyond Standard 90.1) – *in process*
- Extends scope and coverage (alterations and additions)
- Includes international units
- Expands climate locations
- Is reorganized for ease of use

## How is it the same?

- Contains separate envelope, HVAC, SWH, and lighting provisions
- Includes envelope tradeoff software (ENVSTD – new version)
- Contains an energy cost budget tradeoff method

## How has stringency changed?

- Mechanical requirements generally more stringent (with exception of economizers)
- Envelope requirements a mixed bag – some more stringent, some less, depending on economics
- Lighting requirements generally more stringent with exception of some building types and space types

## How can I find out more about the differences?

- Excruciatingly detailed comparisons of Standards 90.1-1989 and 90.1-1999 may be found at http://www.energycodes.gov/implement/determinations_com.stm
- PNNL is also working on comparisons of the 90.1-1999 Standard and Chapter 8 of the 2001 IECC

## How can I get a copy?

- Standard 90.1, the Standard 90.1 Users Manual, and the ENVSTD software are available from ASHRAE

- www.ashrae.org

- 404-636-8400

## Comparison of organization of sections of Standard 90.1

- 4 – Compliance
- 5 – Electric power
- 6 – Lighting
- 7 – Auxiliary systems   and equipment
- 8 – Building Envelope
- 9 – HVAC Systems
- 10 – HVAC Equipment
- 11 – SWH
- 12 – Energy management
- 13 -  ECB

- 4 – Administration   and enforcement
- 5 – Building envelope
- 6 – HVAC
- 7 – SWH
- 8 – Power
- 9 – Lighting
- 10 – Other equipment
- 11 - ECB

_*90.1-1989*_

_*90.1-1999*_

_*90.1-2001*_

- _Same as 90.1-1999 with the addition of Appendix F - Addenda_

## Standard 90.1

- Section 1 - Purpose
- Section 2 - Scope
- Section 3 - Definitions, Abbreviations, and Acronyms
- Section 4 - Administration and Enforcement
- Section 5 - Building Envelope
- Section 6 - Heating, Ventilating, and Air-Conditioning
- Section 7 - Service Water Heating
- Section 8 - Power

## Standard 90.1

- Section 9 - Lighting
- Section 10 - Other Equipment
- Section 11 - Energy Cost Budget Method
- Section 12 - Normative References
- Appendices A-D - Mostly envelope related
- Appendix E - Informative References
- _Appendix F – Addenda Description Information_

## Section 1 - Purpose

- To provide minimum requirements for the energy-efficient design of buildings except low-rise residential buildings

## Section 2 - Scope

- New buildings and their systems
- New *portions* of buildings and their systems (additions)
- New systems and equipment in *existing* buildings (alterations)

## Section 2 – Scope (cont’d)

- Envelope
- if heated by a heating system with an output  capacity 3.4 btu/h-ft2 or
- if cooled by a cooling system with a sensible output 5 btu/h-ft2
- Virtually all mechanical and lighting systems are covered

## Scope exceptions

- Too little heating or cooling
- Single-family, multifamily of three stories or less, manufactured or modular homes
- Buildings that don’t use electricity or fossil fuel
- Equipment and portions of building systems that use energy primarily for industrial, manufacturing, or commercial purposes

## Section 3 - Definitions, Abbreviations, and Acronyms

- Over 10 pages of definitions
- 1 page of abbreviations and acronyms
- Defined terms are italicized in text of standard

## Section 4 – Administrationand Enforcement

- Specifies
- what applies to new buildings, existing buildings, additions, and alterations
- exemptions for envelope, HVAC, SWH, power, lighting, and other equipment alterations
- Discusses changes in space conditioning

**Notes:**
Worked out with BOMA representatives.

Standard applies when previously unconditioned space or semiheated space is converted to conditioned space (either heated or cooled).  Note that if a space is already heated (I.e., conditioned), then adding mechanical cooling doesn’t trigger this requirement.

Alterations – “if you touch it, it must comply”

Repairs – don’t usually need to comply (e.g., replacing a broken window)

## Administration and Enforcement (cont’d)

- Addresses
- compliance documentation
- labeling of materials and equipment
- fenestration, doors, insulation, mechanical equipment, and packaged terminal air conditioners
- alternative materials and methods of construction
- inspections

**Notes:**
Labeling
	Fenestration – U-factor, SHGC, and air leakage rate for all manufactured fenestration products must be identified on a permanent nameplate installed on the product by the manufacturer (if no nameplate, installer or supplier must provide a signed and dated certification)
	Doors – U-factor and air leakage rate for all manufactured doors used in the exterior or semi-exterior must be identified on a permanent nameplate installed on the product by the manufacturer (if no nameplate, installer or supplier must provide a signed and dated certification)
	Insulation – the rated R-value must be clearly indicated by an identification mark applied by the manufacturer to each piece of building envelope insulation (certificate for blown-in insulation listing the type of insulation, the manufacturer, rated R-value, and where appropriate, the initial installed thickness, and the coverage area)
	Mechanical Equipment – if not covered by NAECA, must carry a permanent label installed by the manufacturer stating that the equipment complies with the Standard
	Packaged Terminal Air Conditioners – Units with sleeve sizes less than 16 in. x 42 in. must be factory labeled “Manufactured for replacement applications only:  not to be installed in new construction projects.”

Field Inspections – items for inspection include at least:  wall insulation, roof/ceiling insulation, vapor retarders, slab/foundation insulation, mechanical systems, electrical equipment and systems must be available for inspection after installation but before concealment.  Fenestration products must be available for inspection after installation.

## Section 5 – Building Envelope

- General *(Section 5.1)*
- Scope
- Compliance
- Climate
- Space-Conditioning Categories and Basis
- Mandatory Provisions *(Section 5.2)*
- Insulation
- Fenestration and Doors
- Air Leakage
- Prescriptive Building Envelope Option *(Section 5.3)*
- Opaque Areas
- Fenestration
- Building Envelope Trade-Off Options *(Section 5.4)*

## Scope (Section 5.1.1)

- Envelope components that enclose
- conditioned space
- semi-heated space
- Requirements apply to three types of spaces
- Nonresidential
- Residential
- Semi-heated
- Exceptions

**Notes:**
Defining characteristic of nonresidential is they aren’t continuously conditioned

Unconditioned spaces are enclosed spaces within a building that are not conditioned or semiheated; must be completely enclosed by walls, roofs, floors, and/or other envelope components and space must qualify as a cooled space, heated space, or an indirectly conditioned space.
	cooled space – has a cooling system with a sensible output capacity > 5 Btu/hft2 of floor area
	heated space – has a heating system with an output capacity greater than or equal to the thresholds listed in Table 5-G (User’s Guide)
	indirectly conditioned space – has no heating or cooling system but is indirectly heated or cooled due to its proximity to spaces that are heated or cooled
		if heat transfer rate to conditioned space is > heat transfer rate to the exterior
		if there is an air transfer rate between the space and conditioned space that is > 3 air changes per hour

Semi-heated is heated, but not to comfort levels like conditioned space

## Semi-heated space

- Has a heating system with a capacity > 3.4 Btu/h.ft2 (10 W/m2) of floor area but is not conditioned space

**Notes:**
Unconditioned spaces are enclosed spaces within a building that are not conditioned or semiheated; must be completely enclosed by walls, roofs, floors, and/or other envelope components and space must qualify as a cooled space, heated space, or an indirectly conditioned space.
	cooled space – has a cooling system with a sensible output capacity > 5 Btu/hft2 of floor area
	heated space – has a heating system with an output capacity greater than or equal to the thresholds listed in Table 5-G (User’s Guide)
	indirectly conditioned space – has no heating or cooling system but is indirectly heated or cooled due to its proximity to spaces that are heated or cooled
		if heat transfer rate to conditioned space is > heat transfer rate to the exterior
		if there is an air transfer rate between the space and conditioned space that is > 3 air changes per hour

Semi-heated is heated, but not to comfort levels like conditioned space

## Exceptions

- All semi-heated and unconditioned spaces to be clearly indicated on floors plans
- In climates > 1800 HDD65, space may be designated either semi-heated or unconditioned only if approved by the building official

## Envelope Compliance Methods (Section 5.1.2)

**Notes:**
Mandatory provisions must be met regardless of which compliance method is followed.

## Climate (Section 5.1.3)

- Bins based on CDD50 and HDD65
- Locations listed in Appendix D
- If location not listed, select one with “closest” climatic conditions

**Notes:**
CDD50 = for any one day, when the mean temperature is > 50F, there are as many degree-days as degrees F temperature difference between mean temperature and 50F.  Annual cooling degree days (CDD) are the sum of the degree-days over a calendar year.

HDD65 = for any one day, when the temperature is < 65F, there are as many degree-days as degrees F temperature difference between mean temperature and 65.  Annual heating degree-days (HDD) are the sum of the degree-days over a calendar year.

Appendix D includes only those locations in ASHRAE Handbook of Fundamentals

Standard does not provide guidance on what is “closest”

## CDD and HDD

- CDD50 = for any one day, when the mean temperature is > 50F, there are as many degree-days as degrees F temperature difference between mean temperature and 50F.  Annual cooling degree days (CDD) are the sum of the degree-days over a calendar year.
- HDD65 = for any one day, when the temperature is < 65F, there are as many degree-days as degrees F temperature difference between mean temperature and 65.  Annual heating degree-days (HDD) are the sum of the degree-days over a calendar year.

**Notes:**
CDD50 = for any one day, when the mean temperature is > 50F, there are as many degree-days as degrees F temperature difference between mean temperature and 50F.  Annual cooling degree days (CDD) are the sum of the degree-days over a calendar year.

HDD65 = for any one day, when the temperature is < 65F, there are as many degree-days as degrees F temperature difference between mean temperature and 65.  Annual heating degree-days (HDD) are the sum of the degree-days over a calendar year.

Appendix D includes only those locations in ASHRAE Handbook of Fundamentals

Standard does not provide guidance on what is “closest”

## Space-Conditioning Categories and Basis Envelope Requirements Are Specified by Space-Conditioning Categories (Section 5.1.4)

- Each space to be included in a category
- Nonresidential conditioned space
- Residential conditioned space
- Both nonresidential and residential semiheated space
- Spaces in climates > 1800 HDD65 assumed to be conditioned space unless
- space will only be semiheated or unconditioned _and_
- approved as such by the building official

**Notes:**
By SPACE, not BUILDING

## Mandatory Provisions(Section 5.2)

- Insulation *(Section 5.2.1) *_*(Section 5.5.1)*_
- Installation _*(Section 5.5.1.1)*_
- Substantial contact _*(Section 5.5.1.2)*_
- Recessed equipment _*(Section 5.5.1.3)*_
- Location of roof insulation _*(Section 5.5.1.4)*_ and insulation protection _*(Section 5.5.1.5)*_
_*Section 5.2.1 now simply refers to Section 5.5*_
*Required in all compliance paths*

- Mandatory Provisions

**Notes:**
All mandatory provisions must be satisfied regardless of which compliance path (prescriptive, building envelope trade-off, or energy cost budget) is used.

## Mandatory ProvisionsInsulation Installation(Section 5.2.1.1) (Section 5.5.1.1)

- Per manufacturer’s instructions
- Achieve rated R-value
- No open-blown or poured loose-fill insulation
- when ceiling slope is > 3/12
- If eave vents installed
- provide baffling of air vents “to deflect incoming air above the surface of the insulation”
- Metal buildings exception
- If roof and wall insulation is “compressed between roof or wall skin and the structure”

## Mandatory Provisions Substantial Contact(Section 5.2.1.2) (Section 5.5.1.2)

- Install insulation in a “permanent manner in substantial contact with inside surface”
- Flexible batt insulation in floor cavities
- to be “supported in a permanent manner by supports no more than 24 in. o.c.”

## Mandatory Provisions Recessed Equipment(Section 5.2.1.3) (Section 5.5.1.3)

- Do not recess equipment to affect insulation thickness
- Lighting fixtures
- HVAC equipment (includes wall heaters, ducts, and plenums)
- Other
- Exceptions

## Exceptions

- When
- “Total combined area affected (include necessary clearances) is < 1% of opaque area of the assembly, **OR**
- Entire roof, wall, or floor is covered with insulation to the full depth required, **OR**
- Effects of reduced insulation are included in area-weighted calculations”

## Mandatory Provisions Roof Insulation (Section 5.2.1.4) (Section 5.5.1.4)

- Not “installed on a suspended ceiling with removable ceiling panels”

## Mandatory Provisions Insulation Protection(Section 5.2.1.5) (Section 5.5.1.5)

- Cover exterior insulation with protective material
- Sunlight
- Moisture
- Landscaping operations
- Equipment maintenance
- Wind
- Access to attics and mechanical rooms without damaging or compressing insulation
- “Insulation materials in ground contact to have a water absorption rate  0.3% (ASTM C272)”

## Mandatory ProvisionsFenestration and Doors (Section 5.2.2) (Section 5.5.2)

- U-factors
- NFRC 100 or
- Assemblies listed in Appendix A
- SHGC
- NFRC 200 or
- Assemblies listed in Appendix A
- Visible Light Transmittance
- NFRC 200 when building envelope trade-off option is used

**Notes:**
This section tells user where to get the properties of fenestration and doors – it does not contain actual requirements

## U-factor

- Skylights – determine for a slope of 20° above the horizontal
- Labeled and certified by manufacturer
- Exceptions
- “Glazed wall systems in vertical fenestration and skylights” – may use U-factors in A.8.1
- A.8.2 acceptable for other vertical fenestration
- A.7 acceptable for opaque doors
- NAGDM 105 acceptable for garage doors

## Solar heat gain coefficient

- The glazing’s effectiveness in rejecting solar heat gain
- Part of a system for rating window performance
- used by NFRC
- Gradually replacing shading coefficient (SC) in product literature and design standards

**Notes:**
SHGC is the glazing’s effectiveness in rejecting solar heat gain.  SHGC is part of a system for rating window performance used by the National Fenestration Rating Council (NFRC).  SHGC is gradually replacing the older index, shading coefficient (SC) in product literature and design standards.  If you are using glass whose performance is listed in terms of SC, you may convert to SHGC by multiplying the SC value by 0.87.
Your design must have a SHGC less than or equal to that in the prescriptive package.  The SHGC requirement is affected by the projection factor (PF) of qualifying overhangs.

## SHGC (cont’d)

- Overall fenestration area (NFRC 300)
- SC X 0.86
- SHGC for center of glass
- SHGC from A.8.1 for glazed wall systems in vertical fenestration and skylights
- SHGC from A.8.2 for other vertical fenestration

## Visible light transmittance

- A measure of the amount of visible light that passes through fenestration
- Affected by:
- composition of the glass
- coatings
- internal shading devices

**Notes:**
Not regulated, but important in daylighting tradeoff

## Mandatory ProvisionsAir Leakage (Section 5.2.3) (Section 5.5.3)

- Seal, caulk, gasket, or weather-strip
- openings and joints in building envelope
- fenestration and doors per NFRC 400
- loading docks in climates > 3600 HDD
- vestibules and doors separating conditioned space from exterior

## Mandatory Provisions/Air Leakage Building Envelope Sealing(Section 5.2.3.1) (Section 5.5.3.1)

- Joints around fenestration and door frames
- Junctions between walls
- and foundations
- at building corners
- and structural floors or roofs
- and roof or wall panels
- Openings for “utility services through roofs, walls, and floors
- Site-built fenestration and doors
- Building assemblies used as ducts or plenums
- Joints, seams, and penetrations of vapor retarders
- All other openings in the building envelope”

## Mandatory Provisions/Air Leakage Fenestration and Doors(Section 5.2.3.2) (Section 5.5.3.2)

- NFRC 400
- Labeled and certified by manufacturer
- Glazed swinging entrance doors and revolving doors – not to exceed 1.0 cfm/ft2
- All other products – not to exceed 0.4 cfm/ft2
- Exceptions
- “Field-fabricated fenestration and doors”
- Garage doors – NAGDM 105

## Mandatory Provisions/Air Leakage Loading Dock Weatherseals(Section 5.2.3.3) (Section 5.5.3.3)

- > 3600 HDD65
- “Cargo doors and loading dock doors equipped with weatherseals
- To restrict infiltration when vehicles are parked in the doorway”

## Mandatory Provisions/Air Leakage Vestibules (Section 5.2.3.4) (Section 5.5.3.4)

- All exterior doors in tall buildings in cold climates must have a vestibule with
- self-closing doors
- interior and exterior doors must not be open at the same time
- distance between interior and exterior doors not < 7 ft when in closed position (remember ADA!)

## Vestibule exceptions

- Non-entrance doors (mechanical/electrical rooms)
- Vehicle and material handling doors and adjacent personnel doors **OR** revolving doors
- All doors in climates < 1800 HDD65 **OR** in buildings < 4 stories
- All doors that open into spaces < 3000 ft2  **OR** into dwelling units

**Notes:**
Not required < 4 stories because stack effect is smaller and stack effect (along with wind effects) is one of the main drivers of infiltration.  Also, low-rise buildings are generally smaller and there is less traffic through the door.

Certain climates are exempt because the energy savings in mild climates do not justify the expense.

Doesn’t include hot and humid climates even though they could use vestibultes too (less temperature gradient usually between indoor and outdoor temperatures).

## Prescriptive Building Envelope Option (Section 5.3)

- 26 criteria sets for different climate types
- Set = single page that summarizes all prescriptive requirements
- Insulation levels for roofs, walls floors
- Fenestration criteria

**WWR ******** 50% of gross wall area****Skylight-roof ratio ******** 5% of roof area****Each envelope component must separately meet requirements**

**Notes:**
This section is where actual requirements are for glazing

## Designers

- Specify
- R-values for walls, floors, and roofs
- U-factors for opaque doors
- U-factor and SHGC for fenestration **OR**
- Use
- Pre-calculated assemblies from Appendix A

## Envelope Prescriptive OptionOpaque Areas (Section 5.3.1)

- Compliance
- Meet or exceed minimum R-values in _[table](slide50.xml)_
- Only R-value of insulation, not to include air films, etc
**OR**
- Meet maximum U-factor, C-factor, or F-factor for the entire assembly
**OR**
- Perform area-weighted average U-factor, C-factor, or F-factor
- Only if there are multiple assemblies within a _single_ class of construction for a _single_ space-conditioning category

**Notes:**
C-factor (thermal conductance) = time rate of steady-state heat flow through unit area of a material or construction, induced by a unit temperature difference between the body surfaces.  Units of C are Btu/hft2F.  Note that C-factor doesn’t include soil or air films.

F-factor – the perimeter heat loss factor for slab-on-grade floors, expressed in Btu/hft2 F

## Example Table B-13 

- Example Table B-13

## C-factor, F-factor

- C-factor (thermal conductance) – time rate of steady-state heat flow through unit area of a material or construction, induced by a unit temperature difference between the body surfaces.  Units of C are Btu/hft2F.  Note that C-factor doesn’t include soil or air films.
- F-factor – the perimeter heat loss factor for slab-on-grade floors, expressed in Btu/hft2 F

**Notes:**
C-factor (thermal conductance) = time rate of steady-state heat flow through unit area of a material or construction, induced by a unit temperature difference between the body surfaces.  Units of C are Btu/hft2F.  Note that C-factor doesn’t include soil or air films.

F-factor – the perimeter heat loss factor for slab-on-grade floors, expressed in Btu/hft2 F

## Envelope Prescriptive OptionOpaque Areas (Section 5.3.1)

- Roof Insulation *(Section 5.3.1.1)*
- Above-Grade Wall Insulation *(Section 5.3.1.2)*
- Below-Grade Wall Insulation *(Section 5.3.1.3)*
- Floor Insulation *(Section 5.3.1.4)*
- Slab-on-Grade Floor Insulation *(Section 5.3.1.5)*
- Opaque Doors *(Section 5.3.1.6)*

## Envelope Prescriptive OptionRoof Insulation (Section 5.3.1.1)

- Meet or exceed minimum R-value in table
- “Skylight curbs insulated to level of roofs with insulation entirely above deck or R-5, whichever is less”
- Roofs with insulation entirely above deck
- R-value is for continuous insulation
- Interruptions for mechanical equipment  1% of surface of the total roof area

## Roof Insulation (cont’d)

- Metal building roofs
- First value is for
- “insulation draped over purlins and then compressed when metal spanning members attached or
- insulation hung between purlins provided there’s a min. of 1” thermal break between purlins and metal spanning members
- Second value is for double-layer installations with insulation installed parallel to the purlins”
- Attics and other roofs
- R-value is for insulation installed both inside and outside the roof or entirely inside the roof cavity

**Notes:**
Double-layer – continuous insulation – it is assumed that the insulation boards are installed below the purlins and are uninterrupted by framing members.  Insulation exposed to the conditioned space or semiheated space shall have a facing and all insulation seams shall be continuously sealed to provide a continuous air barrier.

## Envelope Prescriptive OptionAbove-Grade Wall Insulation(Section 5.3.1.2)

- Meet or exceed R-value in appropriate table
- Mass walls
- heat capacity determined from Table A-6 or A-7
- R-value is for continuous insulation or when uninterrupted by framing other than metal clips no closer than 24 in. o.c. horizontally and 16 in. o.c. vertically
- Exception – requirement of U-0.151

**Notes:**
Comply with R-value criteria or U-factor requirement for the overall assembly, including thermal bridges
	when a wall is both above grade and below grade and insulated on the interior, the above-grade insulation requirement applies to the entire wall
	when insulation is installed on the exterior of the wall or is integral to the wall (e.g., the cells of a concrete masonry wall are filled) then the wall is divided between the above-grade and below-grade portions and the separate requirements apply to each

Exception example – perlite-filled cores on concrete block

## Above-Grade Wall Insulation (cont’d)

- R-values for
**“****Metal building wall** = insulation compressed between metal wall panels and the steel structure
**Steel-framed wall** = uncompressed insulation installed in the cavity between steel studs
**Wood-framed and other** = uncompressed insulation installed in the cavity between wood studs”; also acceptable to be continuous insulation uninterrupted by studs

## Envelope Prescriptive OptionBelow-Grade Wall Insulation (Section 5.3.1.3)

- Meet or exceed values in appropriate table in Appendix B
- R-value is for continuous insulation
- If framing is used, compliance is based on maximum assembly C-factor

**Notes:**
Insulation not required until the HDD65 > 7200

C-factor includes all layers in the construction assembly but excludes exterior air film and soil effect.

## Envelope Prescriptive OptionFloor Insulation (Section 5.3.1.4)

- Meet or exceed values in appropriate table in Appendix B
- R-values for
**Mass floors** = continuous insulation; if framing is used, compliance is based on maximum assembly U-factor
**Steel joist floors** = uncompressed insulation or spray-on insulation, but is also acceptable for continuous insulation
**Wood-framed and others** = uncompressed insulation, but is also acceptable for continuous insulation

**Notes:**
Waffle slab floors – floor is insulated either on interior above the slab or on all exposed surfaces of the waffle
Floors with beams that extend below the floor slab – floor insulated either on interior above the slab or on the exposed floor and all exposed surfaces of the beams that extend 24 inches and less below the exposed floor

## Envelope Prescriptive OptionSlab-on-Grade Floor Insulation (Section 5.3.1.5)

- Meet or exceed values in appropriate table in Appendix B (includes R-value and depth or width of insulation)
- “Be installed around the perimeter to the distance specified
**Inside foundation wall** – extend downward from top of slab a minimum distance specified or to the top of the footing, whichever is less
**Outside foundation wall** – extend from top of the slab or downward to at least the bottom of the slab and then horizontally to a minimum distance specified”

**Notes:**
In all climates, the horizontal insulation extending outside of the foundation shall be covered by pavement or by soil a minimum of 10 inches thick

## Envelope Prescriptive OptionOpaque Doors (Section 5.3.1.6)

- Meet or exceed maximum U-factors in appropriate table in Appendix B

## Envelope Prescriptive OptionFenestration (Section 5.3.2)

- Criteria apply to fenestration, including windows, glass doors, glass block, plastic panels, and skylights
- Compliance
- Meet or exceed maximum U-factors in table
- Meet or exceed minimum SHGC in table
- Use NFRC ratings or default values in Appendix A

**Notes:**
Two classes of vertical fenestration – operable and fixed.  Operable includes:  casement windows, single-hung, double-hung, sliders, awnings, hoppers, sliding or swinging glass doors, and any other type of window or glass door with at least a portion of the sash operable.  Fixed includes windows that don’t open as well as glass block walls and translucent plastic panels.
U-factors differ between fixed and operable; SHGC does not

## Envelope Prescriptive OptionFenestration (Section 5.3.2)

- Fenestration Area *(Section 5.3.2.1)*
- Fenestration U-Factor *(Section 5.3.2.2)*
- Fenestration Solar Heat Gain Coefficient *(Section 5.3.2.3)*
- Visible Light Transmittance *(Section 5.3.2.4)*

**Notes:**
Two classes of vertical fenestration – operable and fixed.  Operable includes:  casement windows, single-hung, double-hung, sliders, awnings, hoppers, sliding or swinging glass doors, and any other type of window or glass door with at least a portion of the sash operable.  Fixed includes windows that don’t open as well as glass block walls and translucent plastic panels.
U-factors differ between fixed and operable; SHGC does not

## Envelope Prescriptive OptionFenestration Area(Section 5.3.2.1)

- Total vertical fenestration area to be < 50% of gross wall area
- including both fixed and operable vertical fenestration
- Total skylight area to be < 5% of gross roof area
- glass skylights
- plastic skylights with a curb
- all skylights without a curb

## Envelope Prescriptive OptionFenestration U-Factor(Section 5.3.2.2)

- NFRC or meet or exceed maximum U-factors in A-17
- Exception
- “Vertical fenestration complying with Exception (c) to 5.3.2.3 to have a U-factor  U-factor specified for 40% of the gross wall area”

## Envelope Prescriptive OptionFenestration SHGC(Section 5.3.2.3)

- Vertical fenestration
- SHGC values < Table 5.3 (Appendix A-18) for appropriate total vertical fenestration area
- Skylights
- SHGC values < Table 5.3 (Appendix A-18) for appropriate total skylight area
- “No SHGC requirements for semiheated spaces or for buildings in climates > 10800 HDD65”
- Exceptions

**Notes:**
Actual requirements are in Appendix A-18; values in Table 5.3 are those specified for “all” orientations.

In latitudes > 10 degrees, SHGC for north-oriented vertical fenestration shall be calculated separately and not be > specified in Table 5.3 for north-oriented fenestration.  If exception is used, fenestration area used in selecting criteria shall be calculated separately for north-oriented and all other-oriented fenestration.
 For demonstrating compliance for vertical fenestration only, the SHGC in the proposed building shall be reduced by using the multipliers in Table 5.3.2.3 for each fenestration product shaded by permanent projections that will last as long as the building itself.
 Vertical fenestration that is located on the street side of the street=level story only, provided that (1) the street side of the street-level story does not exceed 20 ft in height, (2) the fenestration has a continuous overhang with a weighted average projection factor greater than 0.5, and (3) the fenestration area for the street side of the street-level story is less than 75% of the gross wall area for the street side of the street-level story.  When this exception is utilized, separate calculations shall be performed for these sections of the building envelope and these values shall not be averaged with any others for compliance purposes.  No credit shall be given here or elsewhere in the building for not fully utilizing the fenestration area allowed.  This exception does not apply to the building envelope trade-off option in 5.4 or the energy cost budget option in 11.

## Overhangs

- Standard credits permanent overhangs by adjustment to SHGC
- Size of overhang is determined by projection factor

## Envelope Prescriptive OptionVisible Light Transmittance(Section 5.3.2.4)

- No criteria in the Prescriptive Building Envelope Option, but there are “minimum criteria in the Building Envelope Trade-Off Option”

**Notes:**
Not a requirement for this compliance option

## Building Envelope Trade-Off Option (Section 5.4)

- Building complies if
- It satisfies the provisions of 5.1 and 5.2

- Trade-Off Option

-           EPF 		    	    EPFProposed Building	       Budget Building

- EPF = envelope performance factor
- EPF is calculated using Normative Appendix C
*“**Schedules of operation, lighting power, equipment power, occupant density, and mechanical systems to be the same for proposed building and budget building”*

**Notes:**
EPF is a relative term that approximates the total heating and cooling energy associated with a single square foot of surface

Building Envelope Trade-Off Option cannot be used to make trade offs between the building envelope and the lighting or mechanical systems

Schedules are not “tweakable” in ENVSTD, if you want to tweak, you must use ECB method

## Section 6 - HVAC Compliance

## Simplified Approach Option(Section 6.1)

- Limited to...
- buildings with 1 or 2 stories
- buildings < 25,000ft2
- single-zone systems
- air-cooled or evaporatively-cooled only

- Simplified Approach

**Notes:**
Buildings must meet ALL of these requirements before the simplified approach option may be used.

The Simplified Approach was included so that small buildings could comply with the standard with minimal effort, but be subjected to the same stringency as is in the rest of the standard. Since the requirements fit on two pages it is ideal for a small commercial building. The committee included this simplified approach because 80 to 85% of the building stock is this type of building. 

## Simplified (cont’d)

- Manual changeover or dual set-point thermostat
- Heat pump supplementary control
- No reheat or simultaneous heating and cooling for humidity control
- Time clocks (except hotel/motel...)
- Pipe and ductwork insulated
- “Ducted system to be air balanced to within 10% of design air flow rates”
- Interlocked thermostats to prevent simultaneous heating and cooling
- Exhausts (design capacity > 300 cfm unless continuous operation)
- Optimum start controls (design supply air capacity > 10,000 cfm)

**Notes:**
It is important to remember that the simplified approach has the same stringency as the rest of the standard, they have just been put on two pages for single-zone air- or evaporatively-cooled systems. In doing this the committee had to balance simplicity (fewer pages) with which requirements to include. Therefore some systems, such as those requiring heat recovery or water cooled systems are not included in the simplified approach.

## HVAC Mandatory Provisions(Section 6.2)

- Mechanical Equipment Efficiency *(Section 6.2.1)*
- Load Calculations *(Section 6.2.2)*
- Controls *(Section 6.2.3)*
- HVAC System Construction and Insulation (*Section 6.2.4)*
- Completion Requirements *(Section 6.2.5)*
*Required in both Prescriptive and ECB compliance paths*

- Mandatory Provisions

**Notes:**
All mandatory provisions must be met regardless of whether the Prescriptive or ECB compliance path is used.

## Equipment covered

- Package air conditioners
- Heat pumps
- Chillers
- Furnaces
- Boilers
- Heat rejection equipment
- Packaged terminal room air conditioners

## Equipment covered for the first time in 90.1-1999

- Ground-source heat pumps
- Single- and double-effect absorption chillers
- Heat rejection equipment
- New categories for
- hot water and steam boilers
- replacement PTACs and PTHPs

**Notes:**
PTAC = packaged terminal air conditioner
PTHP = packaged terminal heat pump

Generally the stringency isn’t as high for equipment being covered for the first time. 
During the public review process, extensive work went on with the heat rejection equipment manufacturers and ASHRAE’s technical committee on Cooling Towers to ensure the new efficiency requirements were reasonable.

## HVAC Mandatory ProvisionsMechanical Equipment Efficiency  (Section 6.2.1)

- Tables 6.2.1A – 6.2.1G
- Combination systems to meet all requirements for appropriate space heating or cooling category
- “Gas-fired and oil-fired forced air furnaces with input ratings  225,000 Btu/h to have intermittent ignition or interrupted device and have either power venting or a flue damper
- All furnaces with input ratings  225,000 Btu/h, including electric furnaces, not located in conditioned space, to have jacket losses  0.75% of the input rating”

**Notes:**
Equipment not listed in tables has no minimum performance requirements but still can be used
Equipment covered under EPAct has no minimum efficiency requirements for operation at minimum capacity or other than standard rating conditions

Exceptions – water-cooled centrifugal water-chilling packages that are not designed for operation at ARI Standard 550 test conditions (and thus can’t be tested to meet the requirements in the Table); chillers designed to operate outside of the ranges in the table are not covered by the Standard

## HVAC Mandatory ProvisionsLoad Calculations (Section 6.2.2)

- “Determined in accordance with generally accepted engineering standards and handbooks acceptable to the adopting authority”

**Notes:**
Another difference from the 1989 standard should be noted. It allowed a load safety factor of 10%. To give designers latitude, for example when expansions are planned, there is no longer an oversizing restriction.

## HVAC Mandatory ProvisionsControls (Section 6.2.3)

- _Zone_ Thermostatic controls *(Section 6.2.3.1)*
- Required for each zone
- Dead Band controls
- Set Point Overlap Restrictions
- Off-Hour controls *(Section 6.2.3.2)*
- Automatic Shutdown
- Setback Controls
- Optimum Start Controls
- Shutoff Damper Controls
- Zone Isolation

**Notes:**
A dwelling unit can be considered a single zone.  Exterior walls are considered to have different orientations if the directions they face differ by more than 45 degrees.

Whole idea is to maintain control of energy use; keep thermal control; shut off stuff when it’s not needed.  These only cover presence of controls – nothing in the Standard says how you use them.

## HVAC Mandatory ProvisionsControls (Section 6.2.3)

- Gravity Vent Controls _Ventilation System Controls_ *(Section 6.2.3.3)*
- Stair and Shaft Vent dampers
- Gravity Hoods, Vents, and Ventilator Dampers
- Heat Pump Auxiliary Heat Control *(Section 6.2.3.4)*
- Enclosed Parking Garage Ventilation Controls *(Section 6.2.3.5) -** *_*deleted*_

**Notes:**
Shut off leaks; don’t use heat you don’t need; don’t waste energy you don’t need to.

## HVAC Mandatory ProvisionsControls (Section 6.2.3)

- Humidifier Preheat Controls *(Section 6.2.3.6) *_*(6.2.3.5)*_
- Humidification and Dehumidification Controls *(Section 6.2.3.7) *_*(6.2.3.6)*_
- Freeze Protection and Snow/Ice Melting Systems *(Section 6.2.3.8)** *_*(6.2.3.7)*_
- Ventilation Controls for High-Occupancy Areas *(Section 6.2.3.9) *_*(6.2.3.8)*_
- Exceptions

## HVAC Mandatory Provisions/ControlsDead Band (Section 6.2.3.1.2)

- Thermostats must have a 5°F dead band
- Exceptions
- “Thermostats that require manual changeover between heating and cooling modes
- Special occupancy or applications where wide temperature ranges aren’t acceptable” (e.g., retirement homes) and approved by adopting authority

## HVAC Mandatory Provisions/ControlsSet Point Overlap Restriction(Section 6.2.3.1.3)

- If limit switches, mechanical stops, or software programming for DDC systems are used
- means will be provided “to prevent the heating set point from exceeding the cooling set point minus any applicable proportional band”

## HVAC Mandatory Provisions/ControlsOff-Hour Controls(Section 6.2.3.2)

- Systems with heating/cooling capacity > 65,000 Btu/h _and_ fan > 3⁄4 hp
- Shall have the following off-hour controls
- 	- automatic shutdown
- 	- setback controls
- 	- optimum start controls
- 	- shutoff damper controls
- 	- zone isolation
- Exceptions, “HVAC systems
- serving hotel/motel guestrooms
- intended to operate continuously”

## HVAC Mandatory Provisions/ControlsAutomatic Shutdown(Section 6.2.3.2.1)

- Controls to operate on different time schedules for seven different day-types per week and retain programming and time setting during loss of power for at least 10 hrs
- Each control to have
- occupant sensor, **OR**
- manually-operated timer with maximum two hour duration, **OR**
- interlock to security system

**Notes:**
Occupancy sensor to shut off system if no occupancy for up to 30 minutes
Interlock to security system that shuts off system when security system is activated

Controls to keep the information because people likely wouldn’t reprogram them if they didn’t and programmed settings were lost

## HVAC Mandatory Provisions/ControlsSetback Controls(Section 6.2.3.2.2)

- Applies when heating systems are located where heating design temperature is  40°F and cooling systems located where cooling design temperature < 100°F
- “Heating set point adjustable down to  55°F
- Cooling set point adjustable up to  90°F or to prevent high space humidity levels”
- Exception
- “Radiant floor and ceiling heating systems”

## HVAC Mandatory Provisions/ControlsOptimum Start Controls(Section 6.2.3.2.3)

- “Individual heating and cooling air distribution systems with
- total design supply air capacity > 10,000 cfm
- served by one or more supply fans”
- Control algorithm to at least “be a function of
- difference between space temperature and occupied setpoint and amount of time prior to scheduled occupancy”

## HVAC Mandatory Provisions/ControlsShutoff Damper Controls(Section 6.2.3.2.4) (6.2.3.3.3)

- Motorized dampers for outdoor air supply and exhaust systems
- “Ventilation outside air dampers to be capable of automatically shutting off during
- preoccupancy building warm up, cool down, and setback
- (Except when ventilation reduces energy costs or when ventilation must be supplied to meet code requirements)
- Supply and exhaust dampers to have maximum leakage rate of 3 cfm/ft2 at 1.0 in. w.g. when tested in accordance with AMCA Standard 500”

**Notes:**
Motorized dampers for outdoor air supply and exhaust systems to automatically shut when systems aren’t in use

## HVAC Mandatory Provisions/ControlsShutoff Damper Controls - Exceptions(Section 6.2.3.2.4) (6.2.3.3.3)

- Gravity dampers okay in buildings
- < 3 stories in height
- of any height in climates < 2700 HDD65
- Systems with design outside air intake or exhaust capacity  300 cfm
- if “equipped with motor-operated dampers that open and close when unit is energized and de-energized, respectively”

## HVAC Mandatory Provisions/ControlsZone Isolation(Section 6.2.3.2.5) (6.2.3.2.4)

- Each isolation area
- Maximum 25,000 ft2 zone on one floor
- Ability to shut off airflow to isolation area
- Automatic shutdown device
- Central systems capable of stable operation for smallest isolation area

**Notes:**
HVAC systems serving zones intended to operate or be occupied nonsimultaneously to be divided into isolation areas

## HVAC Mandatory Provisions/ControlsStair and Shaft Vents(Section 6.2.3.3.1)

- Motorized dampers
- can be “automatically closed during normal building operation
- interlocked to open as required by fire and smoke detection systems”

## HVAC Mandatory Provisions/ControlsGravity Hoods, Vents, and Ventilators(Section 6.2.3.3.2)

- “Motorized dampers to automatically shut when spaces served are not in use”
- Exceptions
- Gravity dampers okay in buildings
- < 3 stories in height
- of any height in climates < 2700 HDD65

## HVAC Mandatory Provisions/ControlsHeat Pump Auxiliary Heat Control(Section 6.2.3.4)

- Controls to prevent supplementary heat when heat pump can handle the load
- Exception
- Heat pumps
- with minimum efficiency regulated by NAECA
- with HSPF rating meeting Table 6.2.1B
- (“Includes all usage of internal electric resistance heating”)

## HVAC Mandatory Provisions/ControlsEnclosed Parking Garage Ventilation(Section 6.2.3.5) Deleted

- “Garage ventilation fan systems with total design capacity > 30,000 cfm” to have at least one automatic control
- “capable of staging fans or modulating fan volume as required to maintain CO levels below ASHRAE Standard 62” (only applies to garages used predominantly by gasoline-powered vehicles)
- “complying with 6.2.3.2.1 that’s capable of shutting off fans or reducing fan volume during periods when garage is not in use”

## HVAC Mandatory Provisions/ControlsHumidifier Preheat(Section 6.2.3.6) (6.2.3.5)

- “Automatic valve to shut off preheat when humidification isn’t required”

## HVAC Mandatory Provisions/ControlsHumidification and Dehumidification(Section 6.2.3.7) (6.2.3.6)

- Provide means to prevent simultaneous operation of humidification and dehumidification equipment
- Limit switches, mechanical stops, or software programming (DDC systems)
- Exceptions
- “Zones served by desiccant systems, used with direct evaporative cooling in series
- Systems serving zones where specific humidity levels are required and approved by jurisdiction”
- Computer rooms, museums, and hospitals

## HVAC Mandatory Provisions/Controls Freeze Protection and Snow/Ice Melting Systems (Section 6.2.3.8) (6.2.3.7)

- Automatic controls for
- Freeze protection systems
- “outside air temperatures > 40°F or when conditions of protected fluid will prevent freezing”
- Snow- and ice-melting systems
- “pavement temperature > 50°F and no precipitation is falling and outdoor temperature > 40°F”

## HVAC Mandatory Provisions/Controls Ventilation Controls for High-Occupancy Areas (Section 6.2.3.9) (6.2.3.8)

- Systems with
- “design outside air capacities > 3000 cfm and
- serving areas having an average design occupancy density > 100 people per 1000 ft2
- to have means to automatically reduce outside air intake below design rates when spaces are partially occupied
- Ventilation controls in compliance with ASHRAE Standard 62 and local standards
- Exception
- Systems with heat recovery complying with 6.3.6.1”

## HVAC Mandatory ProvisionsHVAC System Construction and Insulation (Section 6.2.4)

- General (*Section 6.2.4.1) *_*(Section 6.2.4.1.1)*_
- Duct and Plenum Insulation *(Section 6.2.4.2)* _*(Section 6.2.4.1.2)*_
- Duct Sealing *(Section 6.2.4.3) *_*(Section 6.2.4.2.1)*_
- Duct Leakage Tests *(Section 6.2.4.4)* _*(Section 6.2.4.2.2)*_
- Piping Insulation *(Section 6.2.4.5) *_*(Section 6.2.4.1.3)*_

## HVAC Mandatory ProvisionsGeneral (Section 6.2.4.1) (6.2.4.1.1)

- Insulation installed in accordance with industry accepted standards
- Insulation
- Protected from damage due to sunlight, moisture, equipment maintenance, and wind
- Exposed to weather to be suitable for outdoor service
- “Covering chilled water piping, refrigerant suction piping, or cooling ducts located outside the conditioned space to include a vapor retardant located outside the insulation, all penetrations and joints of which to be sealed”

## HVAC Mandatory Provisions/HVAC InsulationDuct and Plenum Insulation(Section 6.2.4.2) (6.2.4.1.2)

- All supply and return ducts and plenums to be insulated per Tables 6.2.4.2A and 6.2.4.2B
- Exceptions

## Exceptions

- “Factory-installed plenums, casings, or ductwork furnished as part of HVAC equipment
- Ducts or plenums located in heated, semi-heated, or cooled spaces
- For runouts < 10 ft in length to air terminals or air outlets, the R-value need not exceed R-3.5
- Backs of air outlets and outlet plenums exposed to unconditioned or indirectly conditioned spaces with face areas > 5 ft2 need not exceed R-2; those  5 ft2 need not be insulated”

## HVAC Mandatory Provisions/HVAC InsulationDuct Sealing(Section 6.2.4.3) (6.2.4.2.1)

- Table 6.2.4.3A
- Seal level based on duct type (supply, exhaust, return) and duct location (outdoors, unconditioned spaces, conditioned spaces)
- Table 6.2.4.3B
- lists sealing requirements based on seal level from Table 6.2.4.3A
- Requirements of 6.2.4.4
- Standard industry practice

## HVAC Mandatory Provisions/HVAC InsulationDuct Leakage Tests(Section 6.2.4.4) (6.2.4.2.2)

- Designed > 3 in. w.c.
- Leak tested
- Representative sections  25% of the total installed duct area shall be tested
- Ratings > 3 in. w.c. to be identified on drawings
- Maximum permitted duct leakage

## Permitted duct leakage

- “Lmax = CLP0.65
- Where Lmax = maximum permitted leakage in cfm/100 ft2 duct surface area”

## HVAC Mandatory Provisions/HVAC InsulationPiping Insulation(Section 6.2.4.5) (6.2.4.1.3)

- Table 6.2.4.5
- Minimum pipe insulation thickness based on fluid design operating temperature range, insulation conductivity, nominal pipe or tube size, and system type (Heating, SWH, Cooling)
- Exceptions
- Factory-installed
- Piping conveying fluids
- “Hot water piping between shut off valve and coil, not > 4 ft in length, when located in conditioned spaces
- Pipe unions in heating systems (steam, steam condensate, and hot water)”

## Fluids

- “design operating temperature range between 60°F-105°F, inclusive”
- that haven’t been heated or cooled through the use of nonrenewable energy or where heat gain or heat loss will not increase energy usage

## HVAC Mandatory ProvisionsCompletion Requirements (Section 6.2.5)

- Record drawings
- Operating and maintenance manuals
- System balancing
- System commissioning

## HVAC Mandatory Provisions/Completion ReqDrawings(Section 6.2.5.1)

- Record drawings of actual installation to building owner within 90 days of system acceptance and include, as a minimum
- “Location and performance data on each piece of equipment
- General configuration of duct and pipe distribution system including sizes
- Terminal air or water design flow rates”

## HVAC Mandatory Provisions/Completion ReqManuals (Section 6.2.5.2)

- Operating and maintenance manuals to building owner within 90 days of system acceptance and include, as a minimum

**Notes:**
To include 
	submittal data stating equipment size and selected options for each piece of equipment requiring maintenance
	operation manuals and maintenance manuals for each piece of equipment requiring maintenance, except equipment not furnished as part of the project.  Required routine maintenance actions shall be clearly identified
	names and addresses of at least one service agency
	HVAC controls system maintenance and calibration information, including wiring diagrams, schematics, and control sequence descriptions.  Desired or field determined set points shall be permanently recorded on control drawings at control devices or, for digital control systems, in programming comments.
	a complete narrative of how each system is intended to operate, including suggested set points

## HVAC Mandatory Provisions/Completion ReqSystem Balancing(Section 6.2.5.3.1)

- Measured and adjusted within 10% of design rates
- Exception
- “Variable speed, variable volume flow distribution systems need not be balanced upstream of a pressure independent device”
- Written report for conditioned spaces > 5000 ft2

**Notes:**
In accordance with generally accepted engineering standards

## HVAC Mandatory Provisions/Completion ReqAir System Balancing(Section 6.2.5.3.2)

- Minimize throttling losses
- For fans with system power > 1 hp
- Adjust fan speed to meet design flow conditions
- “variable flow distribution systems need not be balanced upstream of the controlling device”

## HVAC Mandatory Provisions/Completion ReqHydronic System Balancing(Section 6.2.5.3.3)

- Proportionately balanced to minimize throttling losses
- “Pump impeller trimmed or pump speed adjusted to meet design flow conditions”
- Each system to have either “the ability to measure differential pressure increase across the pump or have test ports at each side of the pump”
- Exceptions

## Exceptions

- “Pumps with pump motors  10 hp
- When throttling results in < 5% of the nameplate hp draw, or 3 hp, whichever is greater, above that required if the impeller was trimmed”

## HVAC Mandatory Provisions/Completion ReqSystem Commissioning(Section 6.2.5.4)

- “Control elements are calibrated, adjusted, and in proper working condition”
- > 50,000 ft2 conditioned area
- Except warehouses and semiheated spaces
- Requires commissioning plan

## HVAC Prescriptive Path(Section 6.3)

- Economizers *(Section 6.3.1)*
- Simultaneous Heating and Cooling Limitation *(Section 6.3.2)*
- Air System Design and Control *(Section 6.3.3)*
- Hydronic System Design and Control *(Section 6.3.4)*
- Heat Rejection Equipment *(Section 6.3.5)*
- Energy Recovery *(Section 6.3.6)*
- Exhaust Hoods *(Section 6.3.7)*
- Radiant Heating Systems *(Section 6.3.8)*
- Hot Gas Bypass Limitation *(Section 6.3.9)*

- Prescriptive Path

## Economizers (Section 6.3.1)

- Air Economizers *(Section 6.3.1.1)*
- Design Capacity
- Control Signal
- High Limit Shutoff
- Dampers
- Relief of Excess Outside Air
- Water Economizers* (Section 6.3.1.2)*
- Design Capacity
- Maximum Pressure Drop
- Integrated Economizer Control* **(Section 6.3.1.3)*
- Economizer Heating System Impact* **(Section 6.3.1.4)*

- Prescriptive Path

## HVAC Prescriptive PathEconomizers (Section 6.3.1)

- Climate and size dependent (Table 6.3.1)
- There are LOTS of exceptions
- Can use air economizers
- 100% of design supply air
- Sequenced with mechanical cooling equipment
- High limit shutoff
- Dampers
- Can use water economizers
- 100% of expected system cooling load
- Maximum pressure drop

**Notes:**
Most systems have to have an economizer.

Exceptions
Individual fan-cooling units with a supply capacity < minimum listed in Table 6.3.1
Systems with air cleaning to meet requirements of 6.1.2 of ASHRAE Standard 62
Where > 25% of air designed to be supplied to the system is to spaces designed to be humidified above 35°F dewpoint temperature to satisfy process needs
Systems with a condenser heat recovery system complying with 6.3.6.2
Systems serving residential spaces where the system capacity is < 5 times requirement in Table 6.3.1
Systems serving spaces whose sensible cooling load at design conditions, excluding transmission and infiltration loads, is  transmission and infiltration losses at an outdoor temp of 60°F 
Systems expected to operate < 20 hr/wk
Where use of outdoor air for cooling will affect supermarket open refrigerated casework systems
Where cooling efficiency meets or exceeds efficiency requirements in Table 6.1.3

## HVAC Prescriptive Path/Air EconomizersDesign Capacity (Section 6.3.1.1.1)

- “System capable of modulating outside air and return air dampers to provide up to 100% of the design supply air quantity as outside air for cooling”

## HVAC Prescriptive Path/Air EconomizersControl Signal (Section 6.3.1.1.2)

- “Dampers capable of being sequenced with the mechanical cooling equipment and shall not be controlled by only mixed air temperature”
- Exception
- “Systems controlled from space temperature (such as single-zone systems)”

## HVAC Prescriptive Path/Air EconomizersHigh Limit Shutoff (Section 6.3.1.1.3)

- Automatically reduce outside air intake to “6.1.2 of ASHRAE Standard 62 when outside air intake will no longer reduce cooling energy usage”
- Control types for specific climates from Table 6.3.1.1.3A
- Settings from Table 6.3.1.1.3B

## HVAC Prescriptive Path/Air EconomizersDampers (Section 6.3.1.1.4)

- Return air and outside air dampers to have maximum leakage rate of 20 cfm
- _Return air and outside air dampers to meet the damper leakage specified in 6.2.3.3.4 (Table 6-B)_

**Notes:**
Requirement in 90.1-1999 changes to second bullet (the requirement in 90.1-2001)

## HVAC Prescriptive Path/Air EconomizersRelief of Excess Outside Air(Section 6.3.1.1.5)

- “Means to relieve excess outdoor air during economizer operation to prevent overpressurizing the building
- Outlet located to avoid recirculation into the building”

## HVAC Prescriptive Path/Water EconomizersDesign Capacity (Section 6.3.1.2.1)

- System capable of
- cooling supply air by indirect evaporation and
- “providing up to 100% of expected system cooling load at outside air temperatures of 50°F dry bulb/45°F wet bulb and below”
- Exception
- or meet “100% of expected cooling load at 45°F dry bulb/40°F wet bulb”

## HVAC Prescriptive Path/Water EconomizersMaximum Pressure Drop(Section 6.3.1.2.2)

- Precooling coils and water-to-water heat exchangers to have either
- Water-side pressure drop of < 15 ft of water **OR**
- Create a secondary loop so the coil or “heat exchanger pressure drop isn’t seen by the circulating pumps when the system is in normal cooling mode”

## HVAC Prescriptive Path/Water EconomizersIntegrated Economizer Control(Section 6.3.1.3)

- Economizers must be “integrated with mechanical cooling systems and be capable of providing partial cooling even when additional mechanical cooling is required”
- Some exceptions to this

**Notes:**
Exceptions include:
Direct expansion systems that include controls that reduce the quantity of outdoor air required to prevent coil frosting at the lowest step of compressor unloading, provided this lowest step is no greater than 25% of the total system capacity
Individual expansion units that have a rated cooling capacity less than 5,000 Btu/h and use nonintegrated economizer controls that preclude simultaneous operation of the economizer and mechanical cooling.
Systems in locations having less than 800 average hours per year between 8am and 4pm when the ambient dry-bulb temperatures are between 55F and 69F inclusive.

## HVAC Prescriptive Path/Water EconomizersEconomizer Heating System Impact(Section 6.3.1.4)

- Designed so economizer operation “doesn’t increase the building heating energy use during normal operation”
- Exception
- Where heating is allowed by 6.3.2

## Simultaneous Heating and Cooling Limitation (Section 6.3.2)

- Zone Controls *(Section 6.3.2.1)*
- Hydronic System Controls *(Section 6.3.2.2)*
- Three-Pipe System
- Two-Pipe Changeover System* *
- Hydronic (Water Loop) Heat Pump Systems* *
- Dehumidification *(Section 6.3.2.3)*
- Humidification* (Section 6.3.2.4)*

## HVAC Prescriptive PathSimultaneous Heating and Cooling Limitation (Section 6.3.2)

- Zone controls capable of operating in sequence the supply of heating and cooling energy to the zone to prevent
- reheating,
- recooling,
- mixing, or
- simultaneously supplying air previously heated or cooled
- Hydronic system controls to prevent reheating or recooling of fluids

## HVAC Prescriptive PathSimultaneous Heating and Cooling Limitation (cont’d)

- Dehumidification controls for humidistats to prevent reheating, mixing, etc
- Humidification controls

## HVAC Prescriptive PathZone Controls (Section 6.3.2.1)

- Capable of operating in sequence the supply of heating and cooling energy to the zone
- Controls prevent
- Reheating
- Recooling
- Mixing or simultaneously supplying air previously heated or cooled
- Other simultaneous operation of heating and cooling systems to the same zone
- Exceptions

## HVAC Prescriptive PathZone Controls - Exceptions

- “Zones for which volume of air that is reheated, recooled, or mixed is no greater than the larger of the following
- Volume of outside air to meet 6.1.3 of ASHRAE 62 for the zone
- 0.4 cfm/ft2 of zone conditioned floor area _with several conditions_
- _30% of zone design peak supply_
- 300 cfm for zones whose peak flow rate totals no more than 10% of the total fan system flow rate
- Any higher rate that can be demonstrated to jurisdiction to reduce overall system annual energy usage...
- Zones where special pressurization relationships, cross-contamination requirements, or code-required minimum circulation rates are such that the variable air volume systems are impractical
- Zones where at least 75% of the energy for reheating or for providing warm air in mixing systems is provided from a site-recovered or site solar energy source”

## HVAC Prescriptive PathHydronic System Controls(Section 6.3.2.2)

- Limit heating and cooling of fluids previously heated or cooled mechanically per 6.3.2.2.1 and 6.3.2.2.3

## HVAC Prescriptive PathThree-Pipe System (Section 6.3.2.2.1)

- No common return system for both hot and chilled water

## HVAC Prescriptive PathTwo-Pipe Changeover System(Section 6.3.2.2.2)

- Common distribution system acceptable if
- deadband from one mode to another is  15°F outside air temperature
- controls to allow operation of  4 hours before changing over
- reset controls so heating and cooling supply temperatures at changeover point no more than 30°F apart

## HVAC Prescriptive PathHydronic (Water Loop) Heat Pump Systems (Section 6.3.2.2.3)

- Controls to provide “heat pump water supply temperature deadband of at least 20°F between initiation of heat rejection and heat addition by central devices”
- Cooling tower bypass or cooling tower isolation dampers
- “A two-position valve at each hydronic heat pump for hydronic systems having a total pump system power > 10 hp”
- Exception
- If system loop temperature optimization controller is used, deadband < 20°F is allowed

## HVAC Prescriptive PathDehumidification (Section 6.3.2.3)

- Humidistatic controls to prevent
- Reheating
- Mixing of hot and cold air streams
- Heating and cooling of same air stream
- Exceptions

## Dehumidification exceptions

- Systems
- capable of reducing supply air flow to 50%, or to minimum ventilation
- under 6.67 tons that can unload at least 50%
- smaller than 3.3 tons
- Process applications
- 75% of reheat or recool energy is recovered or solar

## HVAC Prescriptive PathHumidification (Section 6.3.2.4)

- “Systems with hydronic cooling and humidification systems designed to maintain inside humidity at > 35°F dewpoint temperature shall use a water economizer if required by 6.3.1”

## HVAC Prescriptive PathAir System Design and Control(Section 6.3.3)

- Fan Power Limitation *(Section 6.3.3.1)*
- Variable Air Volume Fan Control *(Section 6.3.3.2)*
- Part-Load Fan Power Limitation
- Static Pressure Sensor Location
- Set Point Reset

## HVAC Prescriptive PathAir System Design and Control(Section 6.3.3)

- HVAC systems with total fan system power > 5 hp to meet 6.3.3.1 and 6.3.3.2
- Fan Power Limitation
- VAV Fan Control

## HVAC Prescriptive PathFan Power Limitation(Section 6.3.3.1)

- Table 6.3.3.1
- By supply air volume and allowable nameplate motor power (constant volume and variable volume)
- Allowable fan system power may be adjusted in certain situations

**Notes:**
Where air systems require air treatment or filtering systems with pressure drops > 1 in. w.c. when filters are clean, or heat recovery coils or devices, or direct evaporative humidifiers/coolers, or other devices to serve process loads in the airstream
If 
design room temperature – supply air temp at cooling design condition = > 20°F

## HVAC Prescriptive PathPart-Load Fan Power Limitation(Section 6.3.3.2.1)

- Individual VAV fans with motors 30 hp
- “Have other controls and devices to result in fan motor demand  30% of design wattage at 50% of design air volume when static pressure set point = 1/3 of total design static pressure, based on manufacturer’s certified fan data”

## HVAC Prescriptive PathStatic Pressure Sensor Location(Section 6.3.3.2.2)

- Placed so controller set point is  1/3 the total design fan static pressure
- Except for digital control systems with zone reset capabilities where it may be at the fan discharge
- If this results in the sensor being located downstream of major duct splits, install multiple sensors in each major branch

## HVAC Prescriptive PathSet Point Reset(Section 6.3.3.2.3)

- “For systems with direct digital control of individual zone boxes reporting to the central control panel
- Static pressure set point reset based on zone requiring the most pressure”

**Notes:**
i.e., set point is reset lower until one zone damper is nearly wide open

## HVAC Prescriptive PathHydronic System Design and Control (Section 6.3.4)

- Hydronic Variable Flow Systems *(Section 6.3.4.1)*
- Pump Isolation *(Section 6.3.4.2)*
- Chilled and Hot Water Temperature Reset Controls *(Section 6.3.4.3)*
- _Hydronic (Water-Loop) Heat Pump Systems __*(Section 6.3.4.4)*_

## HVAC Prescriptive PathHydronic System Design and Control (Section 6.3.4)

- “HVAC hydronic systems with total pump system power > 10 hp shall meet 6.3.4.1 – 6.3.4._4_”
- Hydronic Variable Flow Systems
- Pump Isolation
- Chilled and Hot Water Temperature Reset
- _Hydronic (Water-Loop) Heat Pump Systems_

## HVAC Prescriptive PathHydronic Variable Flow(Section 6.3.4.1)

- HVAC pumping systems to include control valves
- Designed to modulate or step open and close as a function of load
- Designed for variable fluid flow
- Capable of reducing flow rates to  50% of design flow rate
- “Individual pumps serving variable flow systems with a pump head > 100 ft and motor > 50 hp
- Have controls and/or devices resulting in pump motor demand  30% of design wattage at 50% of design water flow”

**Notes:**
Controlled as a function of desired flow or to maintain a minimum required differential pressure
Differential pressure measured at or near the most remote heat exchanger or heat exchanger requiring greatest differential pressure

## HVAC Prescriptive PathHydronic Variable Flow – Exceptions

- Systems where
- “Minimum flow is < minimum flow required by equipment manufacturer for proper operation of equipment served by the system”
- Total pump system power  75 hp
- Systems that include  3 control valves

## HVAC Prescriptive PathPump Isolation (Section 6.3.4.2)

- If chilled water plant has more than one chiller or boiler plant has more than one boiler
- Provide for flow reduction when chiller or boiler is shut down

## HVAC Prescriptive PathChilled and Hot Water Temperature Reset Controls (Section 6.3.4.3)

- Affects systems with design capacity > 300,000 Btu/h
- “To include controls to automatically reset supply water temperatures by representative building loads (including return water temperature) or by outside air temperature”
- Exceptions
- Would result in improper operation
- Hydronic systems with variable flow

## HVAC Prescriptive PathHydronic (Water-Loop) Heat Pump Systems (Section 6.3.4.4)

- _For heat pump loops with total pump system power > 10 hp_
- _Two-position valves at each hydronic heat pump must be provided and interlocked to shut off water flow to the heat pump when the compressor is off   _
- _This basically converts the system into a variable flow system.  As such, these systems must also comply with 6.3.4.1_

## HVAC Prescriptive PathHeat Rejection Equipment(Section 6.3.5)

- “Applies to heat rejection equipment used in comfort cooling systems such as
- air-cooled condensers
- open cooling towers
- closed-circuit cooling towers
- evaporative condensers
- Exceptions
- Heat rejection devices included as an integral part of equipment listed _devices whose energy usage is included_ in Tables 6.2.1A-6.2.1D”

**Notes:**
No requirements in this section, just descriptive information.

## HVAC Prescriptive PathFan Speed Control (Section 6.3.5.2)

- Each fan powered by a motor  7.5 hp have
- capability to operate fan at  2/3 full speed
- “controls to automatically change the fan speed to control the leaving fluid temperature or condensing temperature/pressure of the heat rejection device”
- Exceptions

## Exceptions

- Condenser fans serving multiple refrigerant circuits or flooded condensers
- Installations located in climates > 7200 CDD50
- 1/3 of the fans on a multiple fan application speed controlled

## HVAC Prescriptive PathExhaust Air Energy Recovery(Section 6.3.6.1)

- Incorporate exhaust air energy recovery in systems with
-  70% outside air and  5000 cfm total
- 50% energy recovery effectiveness
- Exceptions

**Notes:**
At least 50% recovery effectiveness required for individual fan systems with both a design supply air capacity  5000 cfm and minimum outside air supply of  70% of design supply air quantity
50% energy recovery effectiveness = a change in enthalpy of outdoor air supply = 50% of difference between outdoor air and return air at design conditions

## Exceptions

- Lab systems meeting 6.3.7.2
- Systems
- “serving uncooled spaces that are heated to < 60°F
- exhausting toxic, flammable, paint or corrosive fumes or dust”
- Requiring dehumidification that employ series-style energy recovery coils wrapped around the cooling coil
- “Commercial kitchen hoods classified as Type 1 by NFPA 96
- Where > 60% of outdoor heating energy is provided from site-recovered or site solar energy
- Heating systems in climates < 3600 HDD65
- Cooling systems in climates with a 2.5% cooling design wet-bulb temperature < 65°F
- Where largest exhaust source is < 75% of the design outdoor airflow”

## HVAC Prescriptive PathHeat Recovery for Service Water Heating (Section 6.3.6.2)

- Condenser recovery required if
- 24 hrs per day **and**
- heat rejection > 6,000,000 Btu/h **and**
- SWH load > 1,000,000 Btu/h

**Notes:**
Condenser heat recovery systems installed for heating or preheating of shw provided all of the following are true
24 hr/day facility operation
Total installed heat rejection capacity of the water-cooled systems > 6,000,000 Btu/h of heat rejection
Design swh load > 1,000,000 Btu/h
Required system to have capacity to provide the smaller of
Facilities that
Employ condenser heat recovery for space heating with a heat recovery design > 30% of the peak water-cooled condenser load at design conditions
Provide 60% of their swh from site solar or site recovered energy or from other sources

## HVAC Prescriptive PathKitchen Hoods (Exhaust)(Section 6.3.7.1)

- Hoods > 5000 cfm to be “provided with makeup air sized for at least 50% of exhaust air volume that is a) unheated or heated to more than 60°F and b) uncooled or cooled without the use of mechanical cooling
- Exceptions
- Where hoods are used to exhaust ventilation air that would otherwise exfiltrate or be exhausted by other fan systems
- Certified grease extractor hoods that require a face velocity no greater than 60 fpm”

## HVAC Prescriptive PathFume Hoods (Exhaust)(Section 6.3.7.2)

- Hood systems with a total exhaust rate > 15,000 cfm to have ONE of the following features
- Operation to < 50% design flow **OR**
- Direct make up at least 75% of exhaust rate at specified conditions **OR**
- Heat recovery for make-up air

**Notes:**
Variable air volume hood exhaust and room supply systems capable of reducing exhaust and makeup air volume to  50% of design values
Direct makeup air supply equal to at least 75% of exhaust rate
heated no warmer than 2°F below room set point, 
cooled no cooler than 3°F above room set point, 
no humidification added, and 
no simultaneous heating and cooling used for dehumidification control
Heat recovery systems to precondition makeup air from fume hood exhaust in accordance with 6.3.6.1 without using any exception

## HVAC Prescriptive PathRadiant Heating Systems(Section 6.3.8)

- Required for unenclosed spaces except loading docks with air curtains
- “Radiant heating systems that are used as primary or supplemental enclosed space heating must be in conformance with the governing provisions of the standard”

**Notes:**
Second bullet basically means that you have to treat radiant heating systems used indoors in the same way that you treat other heating systems.  This affects which buildings are within the scope of the Standard, the semi-heated building vs. conditioned building spaces, zone thermostat controls, reheat, and a host of other controls related to simultaneous heating and cooling.  In all of these, radiant heating is to be considered just like any other heating system, and the requirements of 6.3.8.2 are there purely to emphasize this.

## HVAC Prescriptive PathHot Gas Bypass Limitation(Section 6.3.9)

- Not used (including other evaporator pressure control systems) “unless system is designed with multiple steps of unloading or continuous capacity modulation”
- Exception
- “Unitary packaged systems with cooling capacities  90,000 Btu/h”

## Section 7 - Service Water Heating

- General *(Section 7.1)*
- Mandatory Provisions *(Section 7.2)*
- Sizing of systems _Load Calculations_
- Equipment efficiency
- Service hot water piping insulation
- System controls
- Pools
- Heat traps
- Space heating and water heating
- Service water heating equipment
- Prescriptive Path *(Section 7.3)*

## SWH Compliance (Section 7.1.2)

## SWH Mandatory ProvisionsSizing of SystemsLoad Calculations (Section 7.2.1)

- In accordance with manufacturer’s published sizing guidelines _or generally accepted engineering standards and handbooks_

- Mandatory Provisions

## SWH Mandatory ProvisionsEquipment Efficiency(Section 7.2.2)

- Table 7.2.2
- Equipment not listed in Table 7.2.2 has no minimum performance requirements
- Exception

## Exception

- Water heaters and hot water supply boilers > 140 gal storage capacity don’t “have to meet _standby loss_ requirements when
- tank surface is thermally insulated to R-12.5, **and**
- a standing pilot light isn’t installed, **and**
- gas- or oil-fired water heaters have a flue damper or fan-assisted combustion”

## SWH Mandatory ProvisionsService Hot Water Piping Insulation (Section 7.2.3)

- Table 6.2.4.5, Section 6
- Circulating water heater
- Recirculating system piping, including supply and return piping
- Nonrecirculating storage system
- First 8 ft of outlet piping
- Inlet pipe between storage tank and heat trap
- Externally-heated pipes (heat trace or impedance heating)

## SWH Mandatory ProvisionsSystem Controls (Section 7.2.4)

- Temperature Controls *(Section 7.2.4.1)*
- Temperature Maintenance Controls *(Section 7.2.4.2)*
- Outlet Temperature Controls *(Section 7.2.4.3)*
- Circulating Pump Controls *(Section 7.2.4.4)*

## SWH Mandatory ProvisionsTemperature Controls(Section 7.2.4.1)

- To “allow for storage temperature adjustment from 120°F or lower to a maximum temperature compatible with the intended use
- Exception
- If manufacturer’s installation instructions specify a higher minimum thermostat setting to minimize condensation and resulting corrosion”

## SWH Mandatory ProvisionsTemperature Maintenance Controls (Section 7.2.4.2)

- Automatic time switches or other controls
- “Set to switch off usage temperature maintenance system during extended periods when hot water is not required”

## SWH Mandatory ProvisionsOutlet Temperature Controls(Section 7.2.4.3)

- Automatic time switches or other controls
- To limit maximum temperature of water in faucets in public facility restrooms to 110°F

## SWH Mandatory ProvisionsCirculating Pump Controls(Section 7.2.4.4)

- To limit operation to “a period from the start of the heating cycle to a maximum of five minutes after the end of the heating cycle”

## SWH Mandatory ProvisionsPools (Section 7.2.5)

- Pool heaters to have readily accessible on-off switch
- Pool heaters fired by natural gas to NOT have continuously burning pilot lights
- Vapor retardant pool covers required (unless recovered or solar heat)
- Time switches required

**Notes:**
Pools heated to > 90°F to have pool cover with a minimum insulation value of R-12
Time Switch Exception
Pools deriving > 60% of energy for heating from site-recovered energy or solar energy source
Exceptions
Where public health standards require 24-hr pump operation
Where pumps are required to operate solar and waste heat recovery pool heating systems

## SWH Mandatory ProvisionsHeat Traps (Section 7.2.6)

- Noncirculating systems to have heat traps on both the inlet and outlet piping as close as practical to storage tank (if no integral heat traps)
- Either a device specifically designed for this purpose or
- “Arrangement of tubing that forms a loop of 360° or piping that form the point of connection to the water heater includes a length of piping directed downward before connection to the vertical piping of the supply water or hot water distribution system, as applicable”

## SWH Prescriptive PathSpace Heating and Water Heating (Section 7.3.1)

- “Gas- or oil-fired space heating boiler system (complying with Section 6) is allowed to provide total space heating and water heating when **ONE** of the following conditions is met”
- Single boiler or component that is heating the service water has a certain standby loss in Btu/h
- Jurisdiction agrees use of a single heat source will consume less energy than separate units
- Energy input of the combined boiler and water heater system is < 150,000 Btu/h
- Instructions for determining standby loss are included in this Section

- Prescriptive Path

**Notes:**
Unclear where users can get published n values.
Standby loss not exceeding
(13.3 x pmd + 400) / n; where pmd is probable maximum demand in gal/h and n is the fraction of the year when outdoor daily mean temperature is > 64.9°F

90.1 User’s Manual:  “Unfortunately, this value (n) cannot be found in either Appendix D of the Standard or in the ASHRAE Handbook of Fundamentals.  It can be calculated from an hourly weather file as follows:  1) Assign a day number (from 1 to 365) to all of the dry-bulb values in an annual hourly (8760 hr/yr) weather file.  2) Average the outdoor dry-bulb temperatures for each day to create daily mean dry-bulb temperatures.  3) Count the daily mean dry-bulb temperatures that are greater than 64.9°F and n is that number divided by 365.”

## Standby loss equation

- Standby loss not exceeding
- (13.3 x *pmd* + 400) / *n*; where* pmd *is probable maximum demand in gal/h and* n *is the fraction of the year when outdoor daily mean temperature is > 64.9°F

**Notes:**
Unclear where users can get published n values.
Standby loss not exceeding
(13.3 x pmd + 400) / n; where pmd is probable maximum demand in gal/h and n is the fraction of the year when outdoor daily mean temperature is > 64.9°F

90.1 User’s Manual:  “Unfortunately, this value (n) cannot be found in either Appendix D of the Standard or in the ASHRAE Handbook of Fundamentals.  It can be calculated from an hourly weather file as follows:  1) Assign a day number (from 1 to 365) to all of the dry-bulb values in an annual hourly (8760 hr/yr) weather file.  2) Average the outdoor dry-bulb temperatures for each day to create daily mean dry-bulb temperatures.  3) Count the daily mean dry-bulb temperatures that are greater than 64.9°F and n is that number divided by 365.”

## SWH/Prescriptive PathService Water Heating Equipment (Section 7.3.2)

- “Equipment used to provide the additional function of space heating as part of a combination (integrated) system shall satisfy all requirements for service water heating equipment”

## Section 8 - Power

- Voltage drop
- Completion requirements

- Mandatory Provisions

**Notes:**
Section 8 covers voltage drop and completion requirements (both of these requirements are mandatory).  These two topics will be covered in the next slides.

## Voltage Drop(Section 8.2.1)

- Two types of conductors
- Feeder conductors
- Run between the service entrance equipment and the branch circuit distribution equipment
- 2% maximum voltage drop allowed
- Branch circuit conductors
- Run from the final circuit breaker to the outlet or load
- 3% maximum voltage drop allowed

**Notes:**
Voltage drop requirements currently in Standard only a recommendation in NEC.
Two problems associated with voltage drop (User’s Manual Pg 8-3)
Standard does not consider power loss in transformers, therefore, meeting voltage drop requirements doesn’t guarantee proper equipment operation

## Completion Requirements(Section 8.2.2)

- Owner gets information about the building’s electrical system
- Record drawings of actual installation within 30 days
- Manuals

**Notes:**
Standard doesn’t designate who is responsible for providing this information, but it’s normally assigned to the system installer
Record drawings include:
	- single-line diagram of electrical distribution system
	- floor plans showing location of distribution equipment and areas served by equipment
Manuals:
	- submittal data stating equipment nameplate rating
	- O&M manuals for equipment
	- qualified service agency contacts provided
	- complete narrative and schematic of system as it’s normally intended to operate

## Section 9 - Lighting

- General Application *(Section 9.1)*
- Mandatory Provisions *(Section 9.2)*
- Lighting controls
- Tandem wiring
- Exit signs
- Installed interior lighting power
- Luminaire wattage
- Exterior building grounds lighting
- Prescriptive Path *(Section 9.3)*
- Interior Lighting Power Allowance
- Building Area Method
- Space-by-Space Method
- Exterior Lighting Power Allowance

## Lighting compliance

## Lighting general application

- Interior spaces of buildings
- Exterior building features
- Exterior grounds lighting powered through building
- Exceptions
- Emergency lighting
- Lighting required by life safety statute
- Lighting within living units of buildings
- Decorative gas lighting

## Lighting changes between 90.1-1989 and 90.1-2001

- More efficient lighting
- Less power allowed
- No lighting control credits
- Lighting power allowance now based only on connected lighting power
- No control points for spaces
- No separate lighting controls for daylighted spaces

## Lighting changes between 90.1-1989 and 90.1-2001 (cont’d)

- Automatic shutoff controls required
- Most exterior power requirements replaced with minimum _[efficacy](slide195.xml)__ requirements_
- Parking garages included in interior lighting
- Interior power requirements updated
- More stringent requirements
- Area factors no longer need to be calculated
- Building area allowances no longer depend on size
- Additional power allowances for certain specialty lighting

**Notes:**
These changes are part of the reason why LTGSTD is no longer needed and was not included with 90.1-1999

## Lighting scope

- New construction
- Existing nonresidential and high-rise residential
- If  50% of existing luminaires are replaced
- If renovation increases lighting power
- Control must be readily accessible and located so occupants can see the controlled lighting

## Lighting Mandatory ProvisionsLighting Control (Section 9.2.1)

- Automatic Lighting Shutoff *(Section 9.2.1.1)*
- Space Control *(Section 9.2.1.2)*
- Exterior Lighting Control *(Section 9.2.1.3)*
- Additional Control *(Section 9.2.1.4)*

- Mandatory Provisions

**Notes:**
Local override capability (maximum area for override is an entire floor or 25,000 ft2, whichever is less)

Types of occupancy sensors:  wallbox units and wall and ceiling units
Two means of detecting occupancy:  passive infrared sensors and ultrasound detectors

## Lighting Mandatory ProvisionsAutomatic Lighting Shutoff(Section 9.2.1.1)

- Applies to buildings > 5000 ft2
- Time-scheduling devices that accommodate separate schedules for each floor or each space > 25,000 ft2 **OR**
- Occupant-sensing devices that turn off lights in each controlled space within 30 minutes of last occupant detection **OR**
- Signal from another control or alarm system that indicates area is unoccupied

- Mandatory Provisions

**Notes:**
Local override capability (maximum area for override is an entire floor or 25,000 ft2, whichever is less)

Types of occupancy sensors:  wallbox units and wall and ceiling units
Two means of detecting occupancy:  passive infrared sensors and ultrasound detectors

## Lighting Mandatory ProvisionsSpace Control (Section 9.2.1.2)

- At least one for each room or space enclosed by ceiling-height partitions
- Readily accessible to occupants
- Except for safety or security
- In spaces  10,000 ft2, each control can serve a maximum of 2500 ft2
- In spaces > 10,000 ft2, each control can serve a maximum of 10,000 ft2

**Notes:**
If remote, must have an indicator light and be labeled to identify which lighting it controls

## Lighting Mandatory ProvisionsExterior Lighting Control(Section 9.2.1.3)

- Photocells or astronomical time switch required
- Seven-day electrically-driven, mechanical clocks with trippers, astronomical dial, and four-hour spring-wound storage
- Seven-day or calendar year, electronic programmable time switches with astronomic correction and battery backup
- Any of the timers above with a photocell (in place of astronomical correction)
- Exceptions – lighting for
- Covered vehicle entrances
- Exits from buildings or parking structures
- (where required for safety, security, or eye adaptation)

**Notes:**
Lighting controls must be able to automatically turn lights off during daylight hours or when lighting is not required.  Photocells are most commonly used for this purpose.

## Lighting Mandatory ProvisionsAdditional Control(Section 9.2.1.4)

- Many special lighting applications must be controlled separately
- Display/accent lighting
- Case lighting
- Hotel/motel guest room lighting
- Task lighting
- Nonvisual lighting
- Demonstration lighting

## Lighting Mandatory ProvisionsTandem Wiring (Section 9.2.2)

**Notes:**
Luminaires designed for use with 1 or 3 linear fluorescent lamps > 30W each shall use two-lamp tandem-wired ballasts in place of single-lamp ballasts in place of single-lamp ballasts when 2 or more luminaires are in the same space and on the same control device

## Lighting Mandatory ProvisionsTandem Wiring Exceptions(Section 9.2.2)

- Separated surface or pendant luminaires
- Recessed luminaires more than 10 ft apart
- Other luminaires
- With three-lamp ballasts
- On emergency lighting circuits
- With no available pair
- With one lamp, high frequency, electronic ballast

## Lighting Mandatory ProvisionsExit Signs (Section 9.2.3)

- Exit signs operating at > 20 W must have a source _[efficacy](slide195.xml)__ _ 35 lumens/W
- LED lamps okay
- CF lamps with electronic ballasts usually okay
- Majority of incandescent lamps not okay

**Notes:**
Virtually all LED exit signs are less than 20 W and are therefore permitted (typical size is between 2 and 8 watts)

## Efficacy

- The ratio of light output to watts input
- lumens per watt
- The higher the efficacy, the more efficient the light source
- 40 watt incandescent = 480 lumens
- 40 watt fluorescent = 2640 lumens

## Lighting Mandatory ProvisionsInstalled Interior Lighting Power(Section 9.2.4)

- Includes all permanent and portable interior lighting intended for general, ambient, or task illumination
- Includes lamp, power used by ballast, the control (when applicable), current regulators, and any other power draws associated with the lighting system
- Exception

## Lighting Mandatory ProvisionsException

- “If 2 or more independently operating lighting systems in a space can be controlled to prevent simultaneous operation, can base IILP on lighting system with highest wattage”

## Lighting Mandatory ProvisionsLuminaire Wattage(Section 9.2.5)

- Standard incandescent = max. labeled wattage of the luminaire
- Luminaires with ballasts = wattage of the lamp/ballast combination
- Line voltage track = min. 30 W per foot
- Low voltage track = transformer wattage
- All others as specified

## Lighting power development concept

- Create building space models to calculate power densities with:
- Current product performance data
- Updated efficacy and loss factors
- New building construction data
- IES-recommended light levels
- Professional lighting design consensus

## Lighting Mandatory ProvisionsExterior Building Grounds Lighting (Section 9.2.6)

- Luminaires that operate at > 100 W = efficacy > 60 lumens/W
- Exceptions
- Traffic signals
- Lighting within outdoor signs
- Lighting used to illuminate public monuments or registered historic landmarks
- If an occupancy sensor or motion sensor controls the lighting application

## Lighting Prescriptive PathInterior Lighting Power

- Lots of exemptions
- Calculation methods
- Building area
- Space-by-space
- Trade-offs of interior lighting power allowance among portions of the building for which a different calculation method has been used is not permitted

- Prescriptive Path

## Lighting power allowance exemptions

- Theatrical, stage, film, and video production
- Medical and dental procedures
- Exhibit displays for museums monuments, and galleries
- Plant growth or maintenance
- Integral to equipment or instrumentation installed by manufacturer
- Integral to both open and glass-enclosed refrigerator and freezer cases
- Retail display windows, provided the display is enclosed by ceiling-height partitions
- Interior spaces specifically designated as registered interior historic landmarks
- Integral part of advertising or directional signage
- Exit signs
- Sale or lighting educational demonstration systems
- Athletic playing areas with permanent facilities for TV broadcasting
- Casino gaming areas
- For use in areas specifically designed for the visually impaired

## Lighting Prescriptive PathBuilding Area Method(Section 9.3.1.1)

- Used for projects involving
- An entire building
- A single, independent, and separate occupancy in a multi-occupancy building
- _[Gross lighted area ](slide204.xml)__is multiplied by allowance from Table 9.3.1.1_
- Limitations
- Insensitive to specific space functions and room configurations
- Generally is more restrictive
- Does not apply to all building types -  but “selection of a reasonably equivalent type” is permitted

**Notes:**
The building area method is the easiest to use but has limitations as discussed above.

## Lighting Prescriptive PathGross lighted area

- Sum of total lighted area of a building
- Measured from the exterior faces of the exterior walls or from the centerline of walls separating buildings
- Used in the building area method of determining interior lighting power allowance

**Notes:**
GLA includes basements, mezzanines and intermediate floor tiers, and penthouses, provided these spaces have a headroom height of 7.5 ft. or greater.  Excludes covered walkways, open roofed-over areas, porches and similar spaces, pipe trenches, exterior terraces or steps, chimneys, roof overhangs, and similar features

## Lighting Prescriptive PathBuilding area allowances

- Table 9.3.1.1 – here’s a sample

| Building Type | Lighting Power Density (W/ft2) |
| --- | --- |
| Automotive Facility | 1.5 |
| Convention Center | 1.4 |
| Court House | 1.4 |
| Dining:  Bar Lounge/Leisure | 1.5 |
| Dining:  Cafeteria/Fast Food | 1.8 |
| Dining:  Family | 1.9 |
| Dormitory | 1.5 |
| Exercise Center | 1.4 |
|  |  |

**Notes:**
The building area method is the easiest to use but has limitations as discussed above.

## Lighting Prescriptive PathSpace-by-Space Method(Section 9.3.1.2)

- Identify different building types in your project
- Divide gross lighted area of the building into each of the space types
- Calculate lighting power allowance by multiplying area of space type by lighting power density for that specific space type
- Sum all the allowances
- Advantages
- More flexible
- Applicable to all building types
- Accounts for room geometry (e.g., lighting needs of enclosed office vs. open office)

## Lighting Prescriptive PathAdditional Interior Lighting Power (Section 9.3.1.2.1)

- An increase in the ILPA is allowed for specific space functions when using the space-by-space method
- Decorative – 1.0 W/ft2 in space used
- Fluorescent designed to eliminate glare - .35 W/ft2
- Lighting equipment installed in retail spaces specifically to highlight merchandise in specific space used
- Additional 1.6 W/ft2 _times the area of specific display_, or
- Additional 3.9 W/ft2 _times the area of specific display_ for fine merchandise

## Lighting Prescriptive PathExterior Building Lighting Power (Section 9.3.2)

- Sum of all lighting power allowances for applicable exterior applications
- Building Surface Requirements
- Building entrance with canopy – 3 W/ft2
- Building entrance – 33 W/linear ft
- Building exit – 20 W/linear ft
- Building facades – 0.25 W/ft2
- Exceptions, when equipped with a control device

**Notes:**
In 2001, Building Façade requirement is specifically called out in the section’s text rather than in the table and states:  Exterior building façade lighting power shall not exceed 0.25 W/ft2 of the illuminated area.

## Exceptions

- When equipped with a control device
- Specialized signal, directional, and market lighting associated with transportation
- Public monuments
- Registered historic landmark structures or buildings
- Lighting integral to advertising signage

## Section 10 - Other Equipment

- Changes between 90.1-1989 and 90.1-1999
- No transformer recommendations and requirements
- No subdivision of electrical feeders or provisions for check metering
*Motor efficiency levels are higher and correspond to EPAct (only requirement in this section)*
- Motor efficiency requirement now covers all relevant motors, even if they’re part of equipment rated elsewhere in the Standard
- No exemption for motors running < 1000 hrs/yr

## Section 11 - Energy Cost Budget Method

- The ultimate trade-off method allowing you to trade-off across building systems through the use of annual, hourly simulation tools and a baseline building.
- The only real way to deal with unique designs,  renewables, high-efficiency equipment, etc.
- The basis of the energy portion of the LEED rating
- Limits allowable energy costs of the design to those of a building meeting the Standard

## Section 12 - Normative References

- Normative (read “mandatory”) reference documents
- Includes test methods, rating procedures, and other standards

## Assembly U-Factor, C-Factor, and F-Factor Determination(Normative Appendix A)

- Includes pre-calculated U-factors, C-factors, and F-factors
- Above-grade walls
- Below-grade walls
- Floors
- Slab-on-grade floors
- Opaque doors
- Fenestration

## Building Envelope Criteria(Normative Appendix B)

- Actual prescriptive requirements tables for 26 different climate bins
- These are in an appendix because they would have taken up too much space in Chapter 5 and would have broken up the continuity of the text of the Standard

## Methodology for Building EnvelopeTrade-Off Option in Subsection 5.4(Normative Appendix C) 

- The gory details of how the envelope trade-off option is implemented
- For those familiar with the “old” ENVSTD trade-off, this new trade-off allows trade-offs between roof and wall elements.  The “metric” of trade-off is ultimately an energy dollar trade-off.

## Climate Data(Normative Appendix D)

- Climatic data for a number of US, Canadian, and international locations
- HDD65 and CDD50 for use in envelope calculations
- Heating and cooling design temperatures and the old “number of hours between 8 am and 4 pm with Tdb between 55 and 69” for HVAC calculations

## Informative References(Informative Appendix E)

- Other useful references that are not mandatory
- In general, these are not consensus documents so ASHRAE procedures do not allow them to be mandatory references

## Informative References(Informative Appendix F)

- _Information on addenda to 90.1-1999_