NATL INST of standards & TECH R.I.C.

A1 11 021 54774

/Building materials and structures TA410 ;U48 V1-18;1938-1939 C.I NBS-PUB-C

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Nanonai Bureau of Standards

JUL 16 1943

The program of research on building materials and structures undertaken by the

National Bureau of Standards is planned with the assistance of the following advisory

committee designated by the Subcommittee on Design and Construction of the Central

Housing Committee.

TECHNICAL RESEARCH GROUP

Haeold D. Hynds, Chairman

Walter Junge, Federal Housing Administration, Vice Chairman

Pierre Blotjke, A. C. Shire,

Home Owners' Loan Corporation. United States Housing Authority.

C. W. Chamberlain, George W. Trayer,

Procurement Division. United States Forest Service.

Charles E. Mayette, Elsmere J. Walters,

United States Housing Authority. Quartermaster Corps, War Department.

Vincent B. Phelan, Sterling R. March,

National Bxu"eau of Standards. Secretary.

The program is administered and coordinated by the following staff committee of

the Bureau:

Hugh L. Dryden, Chairman

P. H. Bates W. E. Emley A. S. McAllister

H. C. Dickinson G. E. F. Lundell H. S. Rawdon

The Forest Products Laboratory of the United States Department of Agriculture

is cooperating with the National Bureau of Standards in studies of wood constructions.

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BUILDING MATERIALS AND STRUCTURES REPORTS

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UNITED STATES DEPARTMENT OF COMMERCE • Daniel C. Roper, Secretary

NATIONAL BUREAU OF STANDARDS • Lyman J. Briggs, Director

BUILDING MATERIALS

and STRUCTURES

REPORT BMSl

Research on

Building Materials and Structures

for Use in Low-Cost Housing

by HUGH L. DRYDEN

ISSUED JUNE 16, 1938

The National Bureau of Standards is a fact-finding organization;

it does not "approve" any particular material or method of construction. The technical findings in this series of reports are to be construed accordingly

UNITED STATES GOVERNMENT PRINTING OFFICE • WASHINGTON • 1 93 8

FOR SALE BY THE SUPERINTENDENT OF DOCUMENTS, WASHINGTON, D. C. • PRICE 10 CENTS
Foreword

The National Bureau op Standards begins herewith a new series of pubHcations

Building Materials and Structures Reports. For many years the Bureau has

developed test methods, made tests, and conducted research on building materials,

such as cement, lime, brick, tile, and steel and has cooperated with various agencies

in the formulation of specifications for such materials. The results of this work have

been published in the Journal of Research, or in the trade journals, or are embodied in

specifications of the Federal Government and of cooperating technical societies and

industries.

A new approach has now been made to the problem of applying technical research

in the building industry. This first report in the new series is intended to explain that

approach. Acknowledgment is made to the Central Housing Committee, its various

affiliated groups and cooperating individuals, for their invaluable advice and assistance.

The succeeding reports of the series will deal more particularly with the technical

aspects, with test procedures, and results. They will be issued at irregular intervals as portions of the work are completed.

It is our hope that a wide use of the information and methods given in these reports

will aid in reaching that goal of all housing interests—the provision of a satisfactory

home at a cost within the means of those who are not adequately housed at present.

Lyman J. Briggs, Director.
Research on Building Materials and Structures

for Use in Low-Cost Housing

by HUGH L. DRYDEN

CONTENTS

Page Page Foreword ii IV. Scope 3

I. Introduction 1 V. Cooperation with industry ... 4

II. Objectives 2 VI. Detailed programs 4

III. Procedure 2 VII. No "approvals" 5

I. INTRODUCTION

Progress in every modem industry depends on

technical research to improve old products and

to develop new^ ones. The rapid development

of faster and safer automobiles and airplanes

is a direct consequence of reliance on research

accompanied by freedom from stifling tradition. Railway trains have undergone a strik- ing metamorphosis vdthin the last few^ years

because of the application of the results of

technical research on new^ materials and methods of construction. To many thoughtful per- sons it appears that progress in the building

industry can come only by the same route; in

fact that the only hope of meeting the insistent

demands of society for satisfactory houses

within reach of miUions of wage earners is through new materials and methods of construction made possible by research.

The housing agencies of the Government

early recognized the need of research in answering the many technical questions confronting

them and through the Central Housing Committee, its subcommittees, and affihated groups,

recommended the initiation of a research program with special reference to those materials

and methods suitable for use in low-cost housing. The Congress included the sum of $198,-

000 for such a program in the appropriation

for the National Bureau of Standards for the

fiscal year beginning July 1, 1937.

The program is being formulated with the

advice of representatives of the housing agencies of the Government. The Subcommittee

on Design and Construction of the Central

Housing Committee designated a special group

to cooperate with the Bureau on this program

of technical research. The group consists of

Harold D. Hynds, chairman, C. W. Chamberlain of the Procurement Division, Pierre Blouke

of the Home Owners' Loan Corporation, Walter

Junge of the Federal Housing Administration,

Charles E. Mayette of the Public Works Administration, Vincent B. Phelan of the National

Bm-eau of Standards, George W. Trayer of the

Forest Service, Capt. Elsmere J. Walters of the

Quartermaster Corps of the War Department.

The conduct of the program is entrusted to a committee of Bureau division chiefs, P. H.

Bates, H. C. Dicldnson, H. L. Dryden, W. E.

Emley, G. E. F. Lundell, A. S. McAlKster,

and H. S. Rawdon, under the chairmanship of

H. L. Dryden, who is designated as coordinator

of the program.

A research program is a means of achieving more quickly a wider experience than is possible

in the slow process of service experience. Research is controlled, directed, and accelerated

experience. So long as the quahty and per- formance of a house must be judged by living

in it for 25 or 50 years, the accumulation of

experience is slow, and progress in improving

houses and reducing their cost is correspondingly slow. Laboratory procedures and field

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test methods must be developed for objectively

determining all measurable features of per- formance. While the National Bureau of

Standards may take the lead in conducting

research for the industry and in establishing

test methods, the full benefits of technical

research cannot be realized imtil industry

itself employs scientific and technical personnel

and devotes some part of its resources to experimental development. There is no one house or

appliance, and no single agency in industry or government, which will solve the problem of

low-cost housing. By the cooperative effort of

many groups, much can be accomplished.

The immediate need is for research directed

toward the house as a whole rather than toward

the individual materials of which the house is to be constructed. The manufacturers of

building materials have in many instances

utilized fully the resources of laboratories, but

the objective has naturally been the promotion

of the use of a single material or class of material. The building industry needs many more

groups to assume responsibility for the house

as a whole, develop and market complete

houses, and stand back of the product. The

program outlined in this report is intended to encourage these groups in the study of the

complete house construction.

II. OBJECTIVES

The Intent op Congkess is expressed in the

appropriation act as the "study of the properties and suitabiHty of building materials with

particular reference to their use in low-cost

housing, including the construction of such

experimental structures as may be necessary

for this purpose. Provided, That no part of

this program shall duplicate any work now

being performed by the Forest Products Laboratory of the Department of Agriculture."

The opinions of the sponsors are expressed

in the preliminary report on the program by

the special group organized by the Subcommittee on Design and Construction of the

Central Housing Committee, and in the 162

suggestions received from various agencies of

the Government. According to this preliminary report, the sponsors believe that

:

(a) The results should be made available to the

public.

(b) The program should include

(1) Materials, equipment, and methods already

in use in low-cost housing.

(2) New materials and equipment, and new construction methods.

(c) All available information from whatever source should be included in the reports.

(d) Minimum technical requirements should be

established for the elements of a low-cost house. These requirements would be of inestimable value to State and municipal ofRcials.

(e) The tests should insofar as possible be made

under service conditions, and should include the

effect of different materials in contact.

(f) The effect of obsolete building codes in restricting the use of new constructions should be deter- mined.

(g) The useful life of each construction should be

determined.

The investigation should, insofar as practicable, be so planned and carried out that these

objectives will be attained.

The general objective may then be restated

as follows:

Tofurnish to Government agencies, the building

industry, and the public technical information

from every available source on the engineering

properties of building materials as incorporated

in the structural elements and equipment of a

house, with particular reference to low-cost housing

and including new materials, equipment, and

methods of construction as well as those already

in use. It should be noted that the Bureau will not

consider the sociological and economic questions involved, the hygienic or esthetic questions, or the design of houses. We conceive it to be the function of the social planning agencies

to answer the sociological and economic questions. Public-health authorities are already

active in studying the hygienic questions, and

the design of houses, including style and appeal

to the public taste, lies within the field of the

architect. When questions involving these

matters arise, the recommendations of recognized authorities will be followed. The Bureau

does not presume to endorse or critically evaluate recommendations on these questions, which

are not within the scope of its activities.

III. PROCEDURE

It Is Obvious that the objectives of the sponsors cannot be attained by investigations made

only in a laboratory, although laboratory work

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may contribute greatly to the final solution.

Field surveys of existing houses and the erec- tion of experimental houses for study and test under service conditions may be necessary for

(d) the establishment of minunum technical

requirements, (e) the testing under service conditions, (f) the effect of obsolete building codes,

and in all probability, (g) the useful life of each

construction.

Accelerated weathering tests made in a laboratory do not give results for many constructions

which can be used to estimate the service life with reasonable accurancy. Such tests are, however, helpful because they indicate which

constructions may be expected to give the

longer service. It appeared expedient for this investigation

to consider a house as composed of elements,

i. e., walls, partitions, floors, roof, plumbing,

heating, etc., and to investigate each element.

After determining satisfactory constructions

for each element, there remains the problem of

combining them to produce a satisfactory

house. The combination of a particular wall

with a particular roof, for example, might be

prohibitive in cost, or be subject to corrosion

which would shorten its life. However, it appears that the following advantages will result from the study of the elements of a house

:

(a) These data will be more useful to architects and engineers than data on the individual materials of which the elements are composed.

(b) The cost of investigating elements will be very much less than the cost of investigating full- size houses and the data will be obtained in

less time.

(c) The results will approximate closely those obtained on complete full-size houses.

(d) The effect of different materials in contact can be determined.

(e) The data may indicate either that no radically new and different construction is likely to reduce

the cost of a house appreciably or that some

constructions costing much less than the usual

constructions should be investigated further by

erecting experimental houses and subjecting

them to service conditions.

Insofar as possible, each element should be

complete, i. e., a portion of a complete house

ready for occupancy. For example, a wall

element should be a duplicate of a portion of

the wall for a house, one surface suitable for

exposure to the weather and the other having

the finished surface for the inside of the house.

For this investigation the construction of an

element is defined as the design, dimensions,

materials, method or process of fabrication,

and workmanship of the element. If any appreciable change is made in dimensions, materials, etc., the construction is considered

different. For example, an 8-inch brick wall

is one construction and the same wall plastered on one face is a different construction.

Representatives of the housing agencies of

the Government believed that it was desirable

to include in the program some problems involving combinations of elements. Some of

these problems are durability, thermal insulation, ventilation, simplified practice, and commercial standardization of building materials.

Therefore, it is proposed to study the condensation of moisture within walls, its effect on insulating materials, the corrosion of steel in walls, the preparation of steel for painting,

and the adhesion of paint; the rain penetration

of walls and calking materials for sealing joints to prevent the entrance of water and air; and

the durability of building papers and boards

by means of accelerated weathering tests.

IV. SCOPE

Fortunately the program for the determination of the technical and engineering properties

of the elements of a house does not depend to any great extent upon the number of rooms or

their arrangement, the architectural eftect, or

the relation of the family units to each other,

i. e., whether they are detached houses, row

houses, or apartments in a multistoried building. Obviously, for each architectural plan

problems may arise as, for example, the structural framework and the elevators for a six- story apartment building, which elements may

not have been considered in the program. If satisfactory progress is to be made, it seems

advisable to simplify the program at the risk

of neglecting, for the present, some matters of

fundamental importance.

The program will include elements suitable

for detached houses, row houses, and low-cost

apartment houses. It will include new as well

as conventional constructions. Although all

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problems relating to conventional constructions

have not been solved, the investigation of such

constructions will be limited to the data neces- sary for comparison with new constructions.

A new construction is not necessarily a new

material, but may be a change in the design,

dimensions, method of fabrication, or workmanship of an old material.

To restrict the investigation to constructions

and equipment suitable for a low-cost house, a maximum cost was fixed for each element after a study of the available information on this subject. These costs are sufficiently high to include constructions and equipment suitable for low-cost apartments in cities. The costs for detached suburban and rural houses should be

considerably lower.

The sole purpose of the cost limitation is to

restrict this investigation to constructions and

equipment suitable for a low-cost house. For

new constructions wliich are not widely used

at present, the cost must eventually be much

lower, when they reach mass production. If this investigation is to fulfill its objectives, the

cost of the elements must be much lower than

the maximum cost shown in table 1.

Table 1.Maximum cost of elements of a house

to he studied

[As of July 1937 in Washington, D. C]

Structural elements Maximum cost per square foot

WaUs $0. 60

. 35

. 75

.60

Partitions, not load bearing

Floors, including finish floor on upper

face and ceiling (if any) on lower face-_

Roof, including weatherproofing on upper face and ceiling (if any) on lower

face

Equipment Maximum cost per family of four

Heating plant $400

180

320

400

Lighting

Kitchen equipment, including plumbing,

refrigeration, and storage equipment. _ Bathroom equipment, including special

finish walls and floor, plumbing and

fixtures

It should be remembered that the cost of a house depends upon other factors besides the

cost of the individual elements of the structure and its equipment. Thus the cost of the structure depends upon the size as well as on the cost per square foot of its elements, and the cost of

the mechanical equipment depends upon the

performance demanded. The lowest reasonable

cost will be obtained with a structure of no

larger size and having no more facilities than

are required by standards of decency and health.

V. COOPERATION WITH INDUSTRY

The Problem of obtaining satisfactory housing

at a cost within reach of low-income groups is a complex one, even when attention is confined to the technical problems. Attack must be made

on numerous specific problems relating to the

several elements of a house, the results must be

coordinated, and finally the problems relating

to an assembly of the elements into a house or apartment building solved. It is probable

that there is no unique solution, and that the

solution appropriate for one section of the

country may not be satisfactory for other

sections.

The solution will probably not come from any

single agency. It is believed that the solution

will come most rapidly by encouraging large

numbers of groups witliin the industry to attack

the engineering problems, and by cooperating

with them to improve their products, whatever

the materials or methods of construction, provided the cost is low. If the Bureau should

undertake to develop and sponsor new methods,

its usefulness to other sponsors of new methods

would be limited. Therefore, it seems better

to mobilize the resources of the entire building

industry, relying on industry to initiate new

developments. The Bureau may then perform

the function of a disinterested fact-finding

agency as weU as undertake research on basic

problems confronting all the cooperating groups.

VI. DETAILED PROGRAMS

The Details of the program are subject to change as the work progresses. The projects

approved at the beginning of the program were

as follows:

Structural properties of walls, partitions,

roofs, floors LC502A

Fire resistance of walls, partitions, roofs,

floors LC502C

Thermal insulation LC502J

Moisture condensation

Weathering of roofing materials LC502G

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Floor coverings LC502F

Heating equipment LC502L

Plumbing equipment LC502E

Infiltration and ventilation LC502K

Durability of fiber boards LC502B

Corrosion of painted galvanized steel sheets- _ _ LC502H

Rain penetration of masonry LC502D

Calking materials LC502I

Simplified practice recommendations for building materials Commercial standards for bull ding materials _ . These projects, with three exceptions, are described in detail in mimeographed Letter

Circulars identified by the symbols at the right

in the preceding list, which may be obtained on

request from the Bureau. Because of the in- tensive work on the important problem of moisture condensation at other laboratories, in

particular at the Forest Products Laboratory

and at the University of Minnesota, the work

at the Bureau is of an exploratory nature to determine what study, if any, should be made.

No Letter Circular has as yet been issued on

this project, or on the last two listed.

VII. NO "APPROVALS"

Each Report in this series carries on its title page the following statement: "The National

Bureau of Standards is a fact-finding organization; it does not 'approve' any particular material or method of construction. The technical

j findings in this series of reports are to be construed accordingly." The Bureau determines

I technical facts, bases its reports so far as possible on objective tests in which the personal ele- ment is elimiuated, and avoids the expression

1 of opinions so far as is practicable. On the

basis of tests at the Bureau and other pertinent

\ data, several Government agencies set up

j approved lists of products or appliances, and

through special cooperative arrangements a

j few nationally recognized organizations of consumers and professional men are assisted in es- tablishing such lists for certain special materials.

When nationally accepted standards are

available, and there is reason for the Bureau to undertake the work, the Bureau can certify

that a certain sample tested does or does not

comply with the standard. It does not have

the facilities to police an industry, to determine

whether the manufacturing process is under

satisfactory technical control, or to warrant

that the sample tested is representative of the

commercial product generally available. Even

the proper identification of a given product

sometimes offers considerable difficulty.

Reports in this series should not be construed

as "approvals" for still another reason. To

make the data available more promptly, the

reports on the various properties will be issued

as completed. Each report, therefore, will deal

with one property or group of properties, for example the structural properties. Any agency

giving approvals to constructions should also

consider other properties, such as thermal

insulation, durability, etc. The Bureau does not have the facilities to undertake the testing of any and all materials

for the public. It is the policy of the Bureau

not to compete with commercial testing laboratories, and departmental regulations provide

that the Bureau shall not make tests of materials and appliances for the general public if they can be made elsewhere. A Directory of

Commercial Testing and CoUege Research

Laboratories is published as Miscellaneous

Publication Ml25 of the National Bureau of

Standards. Copies may be obtained from the

Superintendent of Documents, Government

Printing Office, Washington, D. C, at a cost of

15 cents.

Washington, April 21, 1938.

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t
The National Bureau oj <S'tan(ia/'(is was established by act of Congress, approved March

3, 1901, contmviing the duties of the old Office of Standard Weights and Measures of the

United States Coast and Geodetic Survey. In addition, new scientific functions were

assigned to the new Bureau. Originally under the Treasury Department, the Bureau was

transferred in 1903 to the Department of Commerce and Labor (now the United States

Department of Commerce). It is charged with the development, construction, custody,

and maintenance of reference and working standards, and their in tercomparison, improvement, and application in science, engineering, industry, and commerce,

SUBJECTS OF BUREAU ACTIVITIES

Electricity

Resistance Measurements

Inductance and Capacitance

Electrical Instruments Magnetic Measurements

Photometry

Radio

Underground Corrosion

Electrochemistry

Telephone Standards

Weights and Measures Length

Mass

Time

Capacity and Density

Gas Measuring Instruments IH^^ Thermal Expansivity, Dental

Materials, and Identification Weights and Measures Laws

W//f Administration.

Large Capacity Scale Testing

Limit Gages

Heat and Power Thermometry

Pyrometry

Heat Measurements Heat Transfer Cryogenics

Fire Resistance

Automotive Power Plants Lubrication and Liquid Fuels

Optics

Spectroscopy

Polarimetry

Colorimetry and Spectrophotometry

Optical Instruments Radiometry

Atomic Physics, Radium, and

X-Rays

Photographic Technology

Interferometry

Chemistry

Paints, Varnishes, and Bitumi- nous Materials

Detergents, Cements, Corrosion, Etc.

Organic Chemistry

Metal and Ore Analysis, and

Standard Samples

Reagents and Platinum Metals

Electrochemistry (Plating)

Gas Chemistry

Physical Chemistry

Thermo-Chemistry and Constitution of Petroleum

Mechanics and Sound

Engineering Instruments and

Mechanical Appliances

Sound

Aeronautic Instruments Aerodynamics

Engineering Mechanics

Hydrauhcs

Organic and Fibrous Materials Rubber

Textiles Paper

Leather

Testing and Specifications

Fiber Structure Organic Plastics Metallurgy

Optical Metallurgy

Thermal Metallurgy

Mechanical Metallurgy

Chemical Metallurgy

Experimental Foundry

Clay and Silicate Products Whiteware

Glass

Refractories Enameled Metals

Heavy Clay Products

Cement and Concreting Materials Masomy Construction

Lime and Gypsum

Stone

Simplified Practice Wood, Textiles, and Paper

Metal Products and Construction Materials

Containers and Miscellaneoua

Products

Materials-Handling Equipment and Ceramics

Trade Standards

Wood, Wood Products, Paper.

Leather, and Rubber

Metal Products

Textiles Apparel

Petroleum, Chemical and Miscellaneous Products

Codes and Specifications

Safety Codes

Building Codes

Building Practice and Specifi- cations Producer Contacts and Certification Consumer Contacts and Labeling

Office Finance

Personnel Purchase and Stores Property and Transportation

Mail and Files Library

Information

Shops

Instrument Woodworking

Glassblowing

Construction Stores and Tool

Room

Operation of Plant Power Plant

Electrical Piping

Grounds

Construction

Guard

Janitorial