The program of research on building materials and structures, carried on by the

National Bureau of Standards, was undertaken with the assistance of the Central Housing Committee, an informal organization of governmental agencies concerned with

housing construction and finance, which is cooperating in the investigations through a subcommittee of principal technical assistants.

CENTRAL HOUSING COMMITTEE

SUBCOMMITTEE ON TECHNICAL RESEARCH

Walter Junge, Chairman. A. C. Shire, Vice Chairman.

Federal Housing Administration. United States Housing Authority.

Sterling R. March, Secretary.

Albert G. Bear,

Veterans' Administration.

Pierre Blouke,

Federal Home Loan Bank Board (Federal Loan Agency)

.

Carroll W. Chamberlain,

Public Buildings Administration (Federal Works Agency)

.

Joseph M. DallaValle,

Public Health Service (Federal Security

Agency).

John Donovan,

Farm Security Administration (Agriculture).

George E. Knox,

Yards and Docks (Navy).

Vincent B. Phelan,

National Bureau of Standards (Commerce).

Edward A. Poynton,

Office of Indian Affairs (Interior).

George W. Trayer,

Forest Service (Agriculture).

Elsmere J. Walters,

Construction Division (War).

CHAIRMEN OF SECTIONS

Specifications Maintenance Mechanical Equipment

Carroll W. Chamberlain Charles Peters Robert K. Thulman

NATIONAL BUREAU OF STANDARDS

STAFF COMMITTEE ON ADMINISTRATION AND COORDINATION

Hugh L. Dryden, Chairman.

Mechanics and Sound.

Phaon H. Bates, Gustav E. F. Lundell,

Clay and Silicate Products. Chemistry.

HoBART C. Dickinson, Addams S. McAllister,

Heat and Power. Codes and Specifications.

Warren E. Emley, Henry S. Rawdon,

Organic and Fibrous Materials. Metallurgy.

The Forest Products Laboratory of the United States Department of Agriculture

is cooperating with both committees on investigations of wood constructions.

[For list of BMS publications and how to purchase, see cover page iii]
UNITED STATES DEPARTMENT OF COMMERCE • Harry L. Hopkins, Secretary

NATIONAL BUREAU OF STANDARDS • Lyman J. Briggs, Director

BUILDING MATERIALS

and STRUCTURES

REPORT BMS46

Structural Properties of "Scot-Bilt" Prefabricated

Sheet-Steel Constructions for Walls, Floors, and Roofs

Sponsored by The Globe-Wernicke Co.

by HERBERT L. WHITTEMORE, AMBROSE H. STANG,

and VINCENT b. phelan

ISSUED MAY 23, 1 940

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 • I94O

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

This report is one of a series issued by the National Bureau of Standards on the

structural properties of constructions intended for low-cost houses and apartments.

These constructions were sponsored by organizations within the building industry

advocating and promoting their use. The sponsor built and submitted the specimens

described in this report for participation in the program outlined in BMS2, Methods

of Determining the Structural Properties of Low-Cost House Constructions. The

sponsor, therefore, is responsible for the design of the constructions and the description

of materials and methods used in their fabrication. The Bureau is responsible for the

method of testing and for the test results. This report covers only the load-deformation relations and strength of the structural elements of a house when subjected to compressive, transverse, concentrated,

impact, and racking loads by standardized methods simulating the loads to which the

element would be subjected in actual service. Later, it may be feasible to determine

the heat transmission at ordinary temperatures and the fire resistance of these same

constructions.

The Forest Products Laboratory, Forest Service, United States Department of

Agriculture, collaborated in the tests of those constructions which had wood structural

members.

The National Biu-eau of Standards does not "approve" a construction, nor does

it express an opinion as to the merits of a construction, for the reasons given in reports

BMSl and BMS2. The technical facts presented in this series provide the basic data

from which architects and engineers can determine whether a construction meets desired

performance requirements.

Lyman J. Briggs, Director.

[II]
Structural Properties of "Scot-Bilt" Prefabricated Sheet-Steel

Constructions for Walls, Floors, and Roofs Sponsored by

The Globe-Wernicke Co.

by HERBERT L. WHITTEMORE, AMBROSE H. STANG, and VINCENT B. PHELAN

CONTENTS

Page

Foreword ii

I. Introduction 1

II. Sponsor and product 2

III. Specimens and tests 2

IV. Materials 3

1. Steel 4

2. Wood 4

3. Xails 4

4. Screws 4

5. Bolts and nuts 5

6. Mineral wool 5

7. Adhesive 5

8. Roof insulating board 5

9. Roofing 5

10. Gypsum wallboard 5

11. Paint 5 V Wall CQ 6

1. Sponsor's statement 6

(a) Four-foot wall specimens 6

(b) Eight-foot wall specimens 8

(c) Comments 9

Page V. Wall CQ—Continued.

2. Compressive load 10

3. Transverse load 11

4. Concentrated load 11

5. Impact load 12

6. Racking load 14

VI. Floor CR 1.5

1. Sponsor's statement 1.5 (a) Description 15

(b) Comments 18

2. Transverse load 18

3. Concentrated load 18

4. Impact load 19

VII. Roof CS, 19

1. Sponsor's statement 19

2. Transverse load 22

3. Concentrated load 23

VIII. Additional comments bj" sponsor 23

ABSTRACT

For the program on the determination of the structural properties of low-cost house constructions The

Globe-Wernicke Co. submitted 27 specimens representing their "Scot-Bilt" prefabricated sheet-steel wall,

floor, and roof constructions. The wall specimens were subjected to compressive,

transverse, concentrated, impact, and racking loads;

the floor specimens to transverse, concentrated, and

impact loads; and the roof specimens to transverse and

concentrated loads. The transverse, concentrated, and

impact loads were applied to both faces of the wall specimens. The loads simulated the loads to which

the elements of a house are subjected in actual service. The deformation under load and the set after the

load was removed were measured for uniform incre- ments of load. The results are presented in graphs and

in tables.

I. INTRODUCTION

To pro^T-de technical facts on the performance

of constructions which might be used in lowcost houses, to discover promising new constructions, and ultimately to determine the properties

necessary for acceptable performance in actual

service, the National Bureau of Standards has

invited the cooperation of the building industry

in a program of research on building materials

and structures suitable for low-cost houses and

apartments. The objectives of this program

are described in report BMSl, Research on

Building Materials and Structures for Use in Low-Cost Housing, and that part of the program relating to structural properties in report

[1]
BMS2, Methods of Determining the Structural

Properties of Low-Cost House Constructions.

Masonry constructions and wood constructions of types which have been extensively

used in this country for houses were included in

the program because their behavior under

widely different service conditions is laiown to builders and the public. The reports on these

constructions are BMS5, Structural Properties

of Six Masonry Wall Constructions, and

BMS25, Structural Properties of Conventional

Wood-Frame Constructions for Walls, Partitions, Floors, and Roofs. The masonry speci- mens were built by the Masonry Construction

Section of this Bureau, and the wood-frame

specimens were built and tested by the Forest

Products Laboratory at Madison, Wis.

The present report describes the structural

properties of three elements of a house sponsored by one of the manufacturers in the building industry. Compressive, transverse, concentrated, impact, and racking loads were

applied to the wall specimens, simulating the

loads to which the elements of a house are subjected in actual service. Compressive loads on a wall are produced by the weight of the

roof, second floor, and second-story walls, if any, by furniture and occupants, and by snow

and wind loads on the roof. Transverse loads on a wall are produced by the wdnd, concentrated and impact loads by accidental contact

with heavy objects, and racldng loads by the

action of the wind on adjoining walls. Transverse loads are appKed to floors by furniture

and occupants ; concentrated loads by furniture,

for example, the legs of a piano; and impact

loads by objects falling on the floor or by

persons jmnping on the floor. Transverse

loads are applied to roofs by wind and snow;

concentrated loads by persons walking on the

roof, and by tools and equipment when the

roof is constructed and repaired.

The deflection and set under each increment

of load were measured because, considered as a

structure, the suitability of a construction

depends not only on its resistance to deformation when loads are applied, but also on whether

it returns to its original size and shape when

the loads are removed.

II. SPONSOR AND PRODUCT

The specimens were submitted by The GlobeWernicke Co., Cincinnati, Ohio, and repre- sented prefabricated sheet-steel wall, floor, and

roof constructions marketed imder the trade

name "Scot-BUt," and consisting of channelshaped panels locked together by special steel keys.

HI. SPECIMENS AND TESTS

The specimens represented three elements of a house and were assigned the following symbols: Wall, CQ; floor, CR; roof, CS. The

individual specimens were assigned the designations given in table 1.

Table 1.

Specimen designations, wall CQ, floor CR, and

roof CS

Element

Wan_

Do.

Do. Do.

Do.

Do.

Do.

Do.

Floor Do.

Do.

Roof- Do.

Specimen

designation

CI, C2, C.?.._ Tl, T2, T3—

Pit, P5, P6 a. 11,19,13 U,I5,ie

R1,R?, R3...

Tl, TS... P1,PZ,PS^.

11,12,13

Tl, T2, TS. PI, P2. PS I

Load

Compressive..

Transverse do

Concentrated- do Impact

do Racking

Transverse Concentrated- Impact

Transverse Concentrated

Load applied

Upper end.

Inside face. Outside face. Inside face. Outside face. Inside face. Outside face.

1 in. below upper end. Upper face. Do.

Do. Do.

Do.

a The concentrated and transverse loads were applied to the same

specimens. The transverse loads were applied first.

!> The concentrated and impact loads were applied to the same speci- mens. The concentrated load was applied first.

Except as mentioned below, the specimens were tested in accordance with BMS2, which

report also gives the requirements for the speci- mens and describes the presentation of the

results of the tests, particularly the load-deformation graphs.

Because, under compressive load, there may

be local shortening at the floor plate and top

plate, the shortenmg of the entire specimen

may not be proportional to the value obtained

from compressometers attached to the specimen over only a portion of its height. Therefore, the shortenings and sets were measured

with compressometers attached to the steel plates through which the load was applied, not

attached to the specimen as described in BMS2.

The lateral deflections under compressive

loads were measured with a deflectometer of

[2]
fixed gage length, which consisted of a Hght

(durakimin) tubular frame having a leg at one

end and a hinged plate at the other. The deHectometer was attached to the specimen by

J clamping the hinged plate near the upper end of

' either face. It was then in a vertical position,

with a gage length (distance between the points

of support) of 7 ft 6 in. A dial micrometer was

attached to the frame at midlength, with the

spindle in contact with the face of the wall speci- men. The dial was graduated to 0.001 in.,

i and readings were recorded to the nearest tenth

! of a division. There were two deflectometers on the specimen, one near each edge adjacent

to the outer joints. This method of measure- ment was used instead of the taut-wire mirrorscale method described in BMS2.

For the transverse load the wall specimens were placed in a vertical position as for masonry

[| waUs and the lateral deflections measured in the

;| same way as imder compressive load.

The indentation under concentrated load

1 and the set after the load was removed were

I measured, not the set only, as described in

BMS2. The apparatus is shown in figure 1. The load was applied to the steel disk, A, to which the crossbar, B, was rigidly attached.

The load was measured by means of the dyna1 mometer, C. Two stands, D, rested on the

|j face of the specimen, each supporting a dial

1 micrometer, E, the spindle of which was in

jl contact with the crossbar about 8 in. from the

1 disk. The micrometers were graduated to 0.001 in. and readings were recorded to the

ji nearest division. The niitial reading (average

I of the micrometer readings) was observed under

the initial load, which included the weight of

the disk and dynamometer. A load was applied

II to the disk, and the average of the micrometer

( readings minus the initial reading was taken

as the depth of the indentation under load.

The deformations under racking load were

i, measured with a right-angle deformeter, conI sisting of a steel channel and a steel angle

I braced to form a rigid connection. In use, the

channel of the deformeter, supported by two

steel plates, in. thick and 4 in. square, rested

I along the top of the specimen, with the steel angle extending downward in the plane of the

I specimen. Two pins passed snugly through

I holes in the channel into the top of the speciFiGTJRE 1.

Apparatus for concentrated load test. A, disk: B, crossbar; C, spring dynamometer; D, stand; E, dial mi

cromcter.

men. A dial micrometer was attached to a

steel block which was in contact with the edge

of the specimen near the stop. The spindle of

the micrometer was in contact with the steel angle of the deformeter. The gage length

(distance from the top of the specimen to the

center of the steel block) was 7 ft 1 1 }i in. The

micrometer was graduated to 0.001 in. and

readings were recorded to the nearest division.

This deformeter was used instead of the taut- wire mirror-scale device described in BMS2.

The tests were begun June 30, 1939, and completed July 13, 1939. The sponsor's representative witnessed the tests.

IV. MATERIALS

The information on the materials was

obtained from the sponsor and from inspection

of the specimens. The Forest Products Laboratory assisted by identifying the species of the

wood in the nailing strips, subflooring, and

finish flooring. The Engineering Mechanics

Section of the National Bureau of Standards

[3]
determined the moisture content of the wood

and the weight and strength of the gypsum

wallboard.

1. Steel

Sheets. —Hot-rolled, annealed, and pickled.

The specified chemical composition of the steel

is given in table 2 and the mechanical properties

in table 3. Carnegie-Illinois Steel Corporation.

Table 2.

Specified chemical composition of the sheet

steel

Element

Content

Minimum Maximum

Carbon_ ._ _ Percent Percent

0. 12 .50

.05

.04

Manganese . . _ 0. 20 Phosphorus . . Sulfur

Table 3.Mechanical -properties of the sheet steel

Yield point Tensile strength Elongation in 8 in.

Minimum Maximum Minimum Maximum Minimum Maximum

lb/in.Ib/inJ Percent Percent

24,000 34, 000 37; 000 50, 000 17 22

Welds.—Electric spot welds, K-in. diam.

They were miide with a 30-kva welding machine, manually operated, manufactured by the

Federal Machine & Welder Co. Before beginning prodiiction, weld specimens were made by

welding two strips of steel and were tested either

by wedging the strips apart with a cold chisel or by rotating the strips in opposite directions.

The adjustment of the welding machine was

considered satisfactory if not less than 98 per- cent of the specimens ruptured in the thinner

sheet.

2. Wood

Nailing strips.—Identified as yellow poplar,

Liriodendron tulipifera.

No. 1 common, by VA^ in., S4S (surfaced

four sides); rabbeted along two edges M in. wide

by %6 in. deep, and grooved at midwidth in. wide by in. deep.

Subflooring.—Identified as southern yellow

pine, Pinus sp. No. 2 common, '^%2 in. thick by 5%^ in. face

width (nominal 1 by 6 in.); dressed, tongueand-grooved, and end-matched.

Finish flooring.—Identified as white oak, •' Quercus sp. i No. 1 common, ^2 in. thick by 2]^ in. face ^ width; dressed, tongue-and-grooved, and endi

matched. ' Spacer blocks.—Yellow poplar. No. 1 common,

S2S; two sizes, 1 by 1 in. and 1% by 2 in. Edge strips.—Yellow poplar. No. 1 common,

%by2m., S2S.

'

Moisture content.—The moisture content of

^ the subfloormg, determined for six pieces from I each specimen, was 13 percent, based on the ' weight when dry; and the moisture content of I the finish flooring, determined for six pieces

from each specimen, was 9 percent. An elec- trical moisture meter was used for determining i the moisture content. To calibrate the meter s for the wood in the subflooring and finish floor- J ing, six samples of each were dried in an oven i at 212° F until the weight was constant. The i moisture content was the difference between the

initial weight and the weight when ovendry, - expressed as a percentage of the weight when i ovendry. The average value for the southern < yellow pine (subflooring) was 0.4 greater than ii the average of the meter readings; and for the

oak (finish flooring) was 0.6 less than the \. average of the meter readings. Therefore the I' moisture content of the subflooring was ob- ' tained by adding 0.4 to the meter readings, and I that of the finish flooring by subtracting 0.6. ! The residts were rounded to the nearest whole

number.

3. Nails

'

The nails were made from steel wire and are

j described in table 4. \^Tleeling Steel Corpora- I' tion. Table 4.

Description of nails

Type Size [

Length steel

wire

gage

Diameter of

wire,

uncoated

Head Finish

Brad, common, light- gage

Pen- ny in.

2

No.

16

in.

0. 0625

in.

Bright. Common 4 Cement-coated. m

121/2 .0985 Do 7 121/4 .0985 Do.

Finishing _ 4 15 .0720 Bright. Plasterboard 1 13 .0915 Blued.

4. Screws

Self-tapping, case-hardened, cadmium-plated; three sizes: No. 6 (0.138-in. diam), '% in.

[4]
long, 18 threads per in., countersunk oval

head; No. 8 (0.164-m. diani), two lengths, % in. and l/{ in., 15 threads per in., binding head;

No. 10 (0.190-in. diam), VA in. long, 12 threads

per in., binding head. Parker-Kalon Co.,

Type "A."

5. Bolts and Nuts

Stove bolts, mild steel, %-in. diam, %-in. long,

16 threads per in., threaded full length, cadmium-plated. Hexagon nuts, % in. thick, % in. across flats, cadmium-plated.

6. Mineral Wool

Mineral wool, made from a mixture of lead

blast-furnace slag, flint rock, iron oxide, and

other siliceous materials, melted at high temperatm'e. A jet of steam blow^s a stream of the

molten mixture into woolly fibers. The specific

gravity is about 1.6. The fibefs are felted into batts 4 in. thick and

15 by 48 in The thermal conductivity is 0.27

(Btu/hr ft^)/(°F/in.) at 103° F. To ' provide

a vapor barrier a waterproof kraft paper,

weight 50 lb/ream (2,880 ft^), is fastened to one

side of the batts by emulsified asphalt adhesive.

The paper was manufactured by the Scutan

Division of the Union Bag & Paper Corporation. Mineral-wool batts, Eagle-Picher Lead

Co., "Eagle Type H3 Ful-Thik."

7. Adhesive

Emulsified asphalt, composed of 74 percent

of bituminous material, 17 percent of asbestos

fiber, and 9 percent of fine mineral filler. Moisture content less than 0.1 percent. Specific

gravity at 77° F, 1.140. Ash content, after calcining at red heat, 22 percent. Philip Carey

Co., "Noah's Pitch."

8. Roof Insulating Board

Wood-fiber boards, manufactured by treat- ing wood with high-pressure steam, without the use of chemicals, then felting together the

residting fibers and compressing into boards.

Roof insulating boards, 1 in. thick, 48 by 50

in.; thermal conductivity, 0.33 (Btu/hr ft^)/ (°F/in) ; and water absorption after 72-hr immersion, 15.8 percent by volume. Masonite

Corporation, "Masonite" roof insulation.

9. Roofing

Felt.—Rag base, saturated with asphalt;

weight, 15 lb/100 fV; roll widtii, 36 in. PliiUp

Carey Co., "Feltex."

Asphalt.—Blended; softening point, 190° to 200° F; penetration, determined in accordance

with ASTM Standard D 5-25, at 77° F (weiglit on needle, 100 g; time, 5 sec), 25 to 35; penetration at 32° F (200 g, 60 sec), greater than 15; penetration at 150° F (50 g, 5 sec), less than 60;

ductility, determined in accordance with ASTM

D 113-35, greater than 2; solubility in carbon

tetrachloride, determined in accordance with

ASTM D 165-27, 99.5 percent; and percentage

of ash, none. Philip Carey Co., "Nabosar."

10. Gypsum Wallboard

Sheets, in. thick, consisting of a core of gypsum, sheathed in news-lined chipboard. The

core was approximately 98 percent of gypsum

and 2 percent of finely divided cellulose fiber by weight.

The weight was 2,270 lb/1,000 ft^. The

average transverse strength, determined in ac- cordance with Federal Specification SS-W-51a,

Wallboard; Gypsum, was 48 lb loaded parallel

to the fibers of the surfacing and 150 lb loaded

across the fibers. The wallboard complied with

the requirements of the specification for weight

and strength. United States Gypsum Co.,

"Sheetrock."

11. Paint

Gray baking primer, weight 8K lb/gal. The

formula is given in table 5.

Table 5.Formula for the -paint

[Pigment, 16.6 percent; vehicle, 83.4 percent, by weight]

Pigment Vehicle

Ingredient Content, by weight Ingredient Content, by weight

Zinc sulfide. Zinc chromate Lampblack . . . _ .

Percent

94.5

5. 5 Trace

Synthetic resin » Processed china wood

oil and linseed oil Mineral spirits ... VMP naphtha

Percent

20.0

24.0

51.0

5.0

» T.Iodifled polybasic acid, polyhydric alcohol resin. The paint was formulated for use in baking.

The viscosity was 90 to 100 sec (Ford No. 4 cup),

[5]
Figure 2.

Four-foot wall s-pecimen CQ

A, full-width outside panels; B, half-width outside panels; C, nailing

strips; D, full-width inside panels; E, half-width inside panels; F,

spacer blocks; G, floor plate; H, top plate.

and the coverage was 1,000 ft-/gal. The Kay

& Ess Co., "No. 9529 Gray Primer."

V. WALL CQ

1. Sponsor's Statement

Wall CO consisted of prefabricated sheetsteel channels joined at the flanges, the webs

forming the outside face. The inside face was

formed of steel sheets. The space between the

inside and the outside face was filled with mineral wool. The entire surface of the sheet steel was covered with paint.

The price of this construction in Washington,

D. C, as of July 1937, was $0.54/ft2.

(a) Fonr-Foot Wall Specimens

Each 4-ft wall specimen, as shown in figure

2, was 8 ft 0 in. high, 4 ft 0 in. wide, and 3 in. thick. Each specimen consisted of two full- width channel-shaped outside panels. A; two

half-width outside panels, B; nailing strips, C;

two full-width inside panels, D; two half-width

inside panels, E; spacer blocks, F; a floor plate,

G; and a top plate, H.

Outside panels.—The full-width outside panels, A, were sheet steel. No. 18 U. S. Std. Gage

(0.0490 in. thick), 7 ft 11% in. long, 1 ft 4 in. wide, and 2% in. deep. The half-width outside

panels, B, were the same as one-half of a full- width panel, A, divided along the longitudinal

[6]
FiGtTRE 3.

Details of wall CQ.

A, outside panel; C, nailing strip; D. inside panel; G, floot plate; H, top plate.

FiGUHE 4.

Slot and key.

center line. They are not used in a house.

The flanges on adjacent panels enclosed a wood

nailing strip, as shown in figure 3. There were six longitudinal slots in each

flange, VVa in. from the web, spaced 1 ft 6 in. on centers. The centers of the end slots were

2^^{6 in. from the ends of the panel. The panels were locked together by H -shaped keys,

shown in figure 4, which were inserted through

the slots, turned 90°, and driven against one end of the slot. The keys were sheet steel. No.

11 U. S. Std. Gage (0.1225 in. thick), plated

with cadmium. The position of a key in a

slot is shown in figure 5.

218548°—40 2 [7]
Mineral-wool batts were fastened by emulsified asphalt adhesive to the inner surface of the full-width outside panels.

Nailing strips.—The nailing strips, C, were

yellow poplar, 7 ft 11% in. long, 2^i2 by V/m in.,

S4S. The strips were enclosed by the flanges

of the outside panels.

Inside panels.—The fuU-wHdth inside panels,

D, were sheet steel, No. 18 U. S. Std. Gage

(0.0490 in. thick), 7 ft 11% in. long, 1 ft 4 in. wide. The longitudinal edges were flanged %

in. The half-width inside panels, E, were the same as one-half of a full-width panel, D,

divided along the longitudinal center line. They

are not used in a house.

The flanges of the panels fitted into the

grooves in the nailing strips, and each panel was fastened to a nailing strip at each edge by

^^-in. No. 6 self-tapping screws, spaced 1 ft 6

in. The screws passed through the face of each

panel into the thicker portion of each nailing

strip.

Spacer blocks.—The spacer blocks, F, were

yeflow poplar, 2^yj^ in. long, 1 by 1 in., S2S,

nine blocks along each edge of the specimen,

spaced 1 ft on centers. Each spacer was fas- tened to each face by one '^-in. No. 8 self-tapping

Figure 5.

Position of key in slot. Method of locking together adjacent panels in wall, floor, and roof conEtructions.

screw through the half-width panels into the

end of the spacer. These spacer blocks are not

used in a house.

Floor plate.—The floor plate, 6, was a sheetsteel angle, No. 12 U. S. Std. Gage (0.1072 in. thick), 3 ft n^Vi, in. long, 3 by 3% in. There

were three 1-in. holes for anchor bolts in the

horizontal (3%-in.) leg, spaced 1 ft 6 in. on

centers a,nd 1% in. from the face of the vertical

(3-in.) leg. The end holes were spaced 5^^ii

in. from the ends of the angle. The floor plate was fastened to the panels by l)^-in. No. 10

self-tapping screws, passing through the vertical

leg of the angle, the face of the inside panels,

the wood nailing strips, and the flanges (of the

outside panels) back of the strips; one screw through each inside panel. Also, the vertical

leg of the floor plate was fastened to the bottom

spacer blocks by %-in. No. 8 self-tapping screws, one into each block.

Top plate.—The top plate, H, was a sheetsteel channel. No. 20 U. S. Std. Gage (0.0368

in. thick), 3 ft ll^^e in. long, 2 by 3% in. It

fitted snugly over the top of the wall panels and was fastened to each outside and inside panel

by one %-in. No. 8 self-tapping screw. On the

outside face the screws passed through the

flange of the top plate and the face of the outside panels; on the inside face, through the

flange of the plate, the face of the inside panels,

and into the thicker portion of the nailing

strips. The plate was also fastened to the top

spacer blocks by No. 8 self-tapping screws, two to each block, one through each flange of the chaimel. This type of top plate is not

used in a house.

Paint.—The entire surface of each piece of

steel was covered in the shop with one coat of primer, applied by spraying, and then baked 1 hour at 200° F.

(6) Eight-Foot Wall Specimens

The 8-ft wall specimens, shown in figure 6, were 8 ft 0 in. high, 8 ft 0 in. face width, and

3 in. thick. They were similar to the 4-ft specimens except that there were six full-width

panels on both faces and no half-width panels

or spacers. There were also two special outside

wall panels, /, ^%e, in. face width, fastened to the outer fianges of the edge full-width panels

in order to make the flange assemblies at the

[8]
Figure 6.

Eight-foot wall s-pecimen CQ.

A, full-width outside panels; C, nailing strips; D, full-width inside panels; G, floor plate; /-/, top i)latc; special outside wall panels.

edges of the specimens like the intermediate

flange assembhes. The over-all width was 8 ft 1% in. As in an actual house, there was a No.

8 self-tapping screw through the contacting

flanges of adjacent wall panels, approximately

ji in. above the lower ends. This fastening was

omitted in the 4-ft specimens.

Both floor plate and top plate were each 7 ft IPXe in. long. All the steel parts were painted

as in the 4-ft wall specimens.

(c) Comments

Standard wall panels are 1 ft 4 in. wide.

Other widths are furnished if required, the

minimum being Aji in. The maximum height

of a single panel is 14 ft 0 in., but panels can be

spliced in the shop to obtain greater heights.

No special equipment or tools are required to assemble the panels for a house.

Any conventional type of masonry foundation may be used. A continuous angle floor plate or sill is set on an asphalt-impregnated

felt strip 3 in. wide and % in. thick. The strip

is laid in a coating of asphalt mastic, with which

it is completely covered before the sill is laid. The sill is fastened by %-in. anchor bolts spaced

about 2 ft 0 in. Corners are 90° panels, 8 by 8 in. Openings

[9]
8

to

(n?

o

o

4

2

0

1 1 / M •

/

1 4> . coy'

1—Q:^

O

•

M—

/• • o d

O-—

o

o

/

1—«

• D a o #•

1 ••

/

%

••

OC ' o

<

^%—

/

/ • op o

/

/ OC

(TfO

' o

1 • •

/

1 CO ^ ^2^^ 0,/^

shortening in

Figure 8.

Compressive load on wall CQ.

LoadTshortening (open circles) and load-set (solid circles) results for speci- mens CQ-Cl, C%, and CS. The load was applied 3.0 in. (one-third the

thicl^ness of the wall) from the inside face. The loads are in liips per

foot of actual width of specimen. The shortenings and sets are for a gage length of 8 ft 0 in., the height of the specimens.

Figure 7. —Wall specimen CQ-Cl imder compressive

load. A, compressometer; B, deflcctometer.

for doors and windows are cased with metal

frames formed from sheet steel, No. 16 U. S. Std. Gage. The frames rest on angle sills, and

the panels above the openings are supported by

angle lintels. Sills and lintels are sheet steel,

No. 12 U. S. Std. Gage.

Wall panels extend above the roof and are capped by a continuous sheet-steel coping,

fastened by screws. Baked enamel finish can be supplied in any

color. Additional i^ainting in the field is not

necessary.

2. Compressive Load

Wall specimen CQ-Cl imder compressive load

is shown in figure 7. The results for wall speci- mens CQ-Cl, C2, and C3 are given in table 6

and in figures 8 and 9.

4

-I

«

1

<• —

i =0-0-

1

o

op

jpo

c po

• o

CO 0 O.I 0.2 0,3

/a/era/ der/ecf/on in, Figure 9.

Compressive load on wall CQ.

Load-lateral deflection (open circles) and load-lateral set (solid circles) results for specimens CQ-Cl, C2, and CS. The load was applied 1.0

in. (one-third the thickness of the wall) from the inside face. The

loads are in kips per foot of actual width of specimen. The defiectiors and sets are for a gage length of 7 (t fi in., the gage length of the deflec- tometers.

10
Table 6.

Structural pr operties of wall CQ

fWeisht, 6.84 Ib/fts]

Compressive load" Transverse load >> Concentrated load Impact load •> Racking load

Specimen Maximum

load Specimen Maximum

load Specimen Maximum

load Specimen

Maximum

licinlit of

droi) Specimen Maximum

load

CI

c Kipslft

8. 02

8. 45

8. 35

Tl

lb/ft'200

188

198

PI _ ill

Jl

ft

J 10.0

'1 10. 0

•1 10. 0

Rt

' Kipslft

0. 85

.74 .70 C2 Tt P2 12..- R2

C3 T3 PS IS Ji3 Average 8. 27 Average 195 Average Average Average d 1, 000 d 10.0 0.76 n 162

163

155

Pi <! 1,000

<! 1, 000

1 1, 000 U <! 10.0

<! 10.0

1 10. 0 T5 PS 15 T6 pe 16.. Averaee . 160 Average d

1, 000 Average J 10.0

» Load applied 1 in. (one-third the thickness of the wall) from the inside face,

b Span 7 ft 6 in. cAkip is 1,0001b.

d Specimen did not fail. Test discontinued. The speed of the movable head of the testing

machine was 0.044 in./min. The lateral deflections shown in figm-e 9 were plotted to the

right of the vertical axis for deflections of

the specimen toward the outside face and to the left of the axis for deflections toward the

inside face. Under a load of 2.5 kips/ft both inside half- width panels of specimens CQ-Cl and C2 separated /8 in. from the nailing strips near midheight. In specimen C3 the same separation

occurred under a load of 3.5 kips/ft. The

edges of the inside face of specimen CI budded

between spacers xmder 3.0 Idps/ft. Under a

load of 8.0 kips/ft the two full-width inside

panels of CI budded, 1 ft from the bottom,

and under the maximum load the flanges of

the outside panel at one edge of the specimen

also buckled, near midheight. In specimen

C2 under a load of 7.0 Idps/ft the two full- width inside panels buckled, one near midheight and the other 1 ft from the bottom.

Under the maximum load the outside panels

budded near the bottom. In specimen C3

imder a load of 8.0 kips/ft one full-width inside

panel buckled 1 ft from the bottom. Under

the maximum load the budded panel folded,

and the separation of the other panels from the

nailing strips was about V/i in.

3. Transverse Load

Wall specimen CQ-T5 tmder transverse load is shown in figure 10. The results are given in table 6 and in figure 1 1 for wall specimens CQ-Tl, T2, and T3, loaded on the

inside face, and in figure 12 for specimens CQTIf., T5, and T6, loaded on the outside face. The inside (loaded) face of specimen CQ-Tl

separated from the nailing strips under a load

of 180 lb/ft ^. In T2 the separation took place

imder a load of 140 Ib/ft^ and in T3 under 120

lb/ft". Under the maxLmimi loads the flanges

of the outside panels budded between the

loading rollers, at the nailing strips. The

faces of the specimens were not damaged.

Under a load of 160 Ib/ft^ on specimens CQTlf- and T5 the loaded (outside) faces buckled

transversely between loading roUers. Under

the maximum load the loaded faces of each of

these specimens continued to crumple, and in

addition the flanges of the outside panels

buckled. In specimen T6 the budding of the

loaded face and of the flanges occurred imder

the maximum load.

4. Concentrated Load

Results of concentrated-load tests are given

in table 6, and in flgure 13 for wall specimens

CQ-Pl, P2, and P3, loaded on the inside face,

and in figure 14 for wall specimens CQ-P4, P5,

and P6, loaded on the outside face. The concentrated loads were appUed to the

inside face of specimens CQ-Pl , P2, and P3 on

the center of a fuU-width inside panel, 15 in. from one end. Under a load of 400 lb on

specimen PI, 500 lb on specimen P2, and 600

lb on specunen P3 the nailing strip along one

edge of the loaded panel split in the groove,

[in
Figure 10. —Wall specimen CQ-T5

under transverse load.

beginning at one end of the strip and extending

IK ft. After a load of 1,000 lb had been

applied to specimens PI, P2, and PS the sets were 0.98, 0.86, and 1.02 in., respectively.

The concentrated loads were applied to the

outside face of specimens CQ-PJf, P5, and P6

on the middle of a full-width outside panel,

15 in. from one end. Under a load of 400 lb on each specinien the panel joints on each side

of the concentrated load opened about }-i in.,

and continued to open further as the load was

increased. Under a load of 700 lb the end of

the loaded panel of specimen made contact

with the opposite face of the wall, which rested on the steel plate. After a load of 1,000 lb

had been apphed to specimens P4, P5, and P6

the sets were 1.18, 1.25, and 1.21 in., re- spectively.

5. Impact Load

Impact-test results are shown in table 6, and in figure 15 for waU specimens CQ-Il, 12,

and IS, loaded on the inside face, and in figure

16 for specimens CQ-IJi-, 15, and 16, loaded on

the outside face. The inipact loads were applied to the center

of the inside face of specimens CQ-Il, 12, and

IS, the sandbag striking the sheet steel directly over the joint between the two full-width

inside panels. The eft'ects are given in table 7.

[12]
200

c 160

40

0

—

p-0—

/

I

1

/

Im—

1 ^ 1/

*r

\[

^7 Off /.e

def/ecf/on in. Figure 11.—Transverse load on wall CQ, load applied

to inside face.

Load-deflection (open circles) and load-set (solid circles) results for specimens CQ-Tl, T2, and TS on the span 7 ft 6 in.

/ooo

800

^ 600

^ 400

200

0

1 • —

/

om

1 — /

I O —o-/<

/

s

/

• • #

oyo

/ —•—#

o—p

/

>-y^>0

/r / •

-c6>—

\/

CO-/ 0 0,4 08 /.2 /.6

indenfaf/'on in. Figure 13.

Concentrated load on wall CQ, load applied

to inside face.

Load-indentation (open circles) and load-set (solid circles) results for specimens CQ-Pl, P2, and PS.
o/ef/ecfion in. Figure 15.

Impact load on wall CQ, load applied to inside face.

Height of drop-defleotion (open circles) and height of drop-set (solid

circles) results for specimens CQ-Il, 12, and IS on the span 7 ft 6 in.

def/ec/hn in,

Figure 16.Impact load on wall CQ, load applied to outside face. Height of drop-deflection (open circles) and height of drop-set (solid

circles) results for specimens CQ-H, IB, and 16 on the span 7 ft 6 in.

Table 7.

Effects of impact load on wall CQ, loaded on

the inside face

Specimen nSpecimen USpecimen

IS

Description of effects •S2

0 ^d eight drop eflec- ;ion

eight drop 0 ^ eg a c 0 Wo Q Wo Q Wo Q

Face loaded; Full-width panels separated U in. ft in. n in. ft in. from each other at midheight 4.0 2, 18 4.0 2. 20 4. 5 2.46 One full-width panel separated I2 in. from outer nailing strip at midheight 7.0 3. 41 6.5 3. 22 7.0 3. 49 Center nailing strip splitlongitudinally. 4,0 2. 18 3.5 1. 97 4.0 2.25 Face not loaded: Full-width panels separated H in. from each other at midheight, e.xcept at the keys 4.0 2. 18 3.5 1. 97 4.0 2. 25

After the 10-ft drop the sets in specimens

CQ-Il, 12, and 13 were 3.62, 3.50, and 3.81 in., I respectively. The outer (half-width) panels on the inside face were buckled slightly.

The impact loads were applied to the center

of the outside face of specimens CQ-IIy, 15, and

16, the sandbag striking the sheet steel directly over the joint between the two full-width

outside panels. The effects are given in table 8. Table 8.

Effects of impact load on wall CQ, loaded on

the outside face

Description of effects

Specimen

U

Specimen

15 Specimen

16

Height of

drop

Deflec- tion Height of

drop

Deflec- tion Height of

drop

Deflec- tion

Face loaded; Full-width panels dished where ft in. ft in. ft in. strucli by sandbag 3.0 1.61 3.0 L58 3,5 1.86 Full-width panels separated in. from each other at midheight,

except at the keys 4.0 2. 10 4.5 2.31 4.5 2.30 One full-width panel buckled H in. inward at floor plate _ 6.0 2. 93 5.0 2.56 6.5 3. 05 One full-width panel buckled M in. Inward at top plate. . 6.0 2.93 7.0 3. 41 6.5 3. 05 Center nailing strip split longitudi- nally 5.0 2.56 5.5 2,62 5.5 2.69 Face not loaded: Full-width panels separated H in. from each other at midheight-. 5.0 2.56 5.5 2.62 5.5 2.69

After the 10-ft drop the sets in specimens

CQ-I4, 15, and 16 were 3.84, 3.68, and 3.70 in.,

[ respectively. The half-width panels on the

| outside face were buckled slightly. ^

6. Racking Load ^

i Wall specimen CQ-R3 under racking load is shown in figure 17. The results for wall ^ specimens CQ-Rl, R2, and R3 are given in i table 6 and in figure 18. i The top plate and one or more outside and

inside panels buckled under loads of 0.6, 0.5,

and 0.3 kip/ft on specimens CQ-Rl, R2, and

R3, respectively. Under the maximum load
on specimen Rl the top plate buckled further,

between screws; all outside and inside panels

buckled ; and two screws through the floor plate

into the middle panels ruptured in tension, due

to the buckling. In specimen R2 under the

maximum load the top plate and all panels

except three on the outside face buckled; the

vertical displacement between adjacent panels was about 0.15 in., and the heads of all the screws connecting the floor plate to the panels

sheared off. In specimen R3 under the maximum load the top plate crumpled further, all panels except one on the inside face and two on

the outside face buckled, and the vertical

displacement between adjacent panels was

about 0.10 in.

VI. FLOOR CR

1. Sponsor's Statement

Floor CR consisted of prefabricated sheetsteel channels joined at the flanges, the webs

forming the lower face. The upper face was composed of subfiooring and finish flooring.

The entire surface of the steel was covered with

paint.

The price of this construction in Washington

D. C, as of July 1937, was $0.56/ft^

(a) Description,

The floor specimens, shown in figiu-e 19, were

12 ft. 6 in. long, 4 ft. 2 in. wide, and 7/4 in. thick.

Each consisted of four full-width channelshaped floor panels, A; two half-width panels,

B; nailing strips, C; spacer blocks, D; edge

strips, E; headers, F; subfiooring, G; and

finish flooring, H.

Floor 'panels.—The full-width floor panels, A,

were sheet steel. No. 18 U. S. Std. Gage (0.0490

in. thick), 12 ft. b'^Yif, in. long, 10 in. wide, and

6 in. deep. The half-width floor panels, B, were the same as one-half of a full-width panel,

A, divided along the longitudinal center line.

[15]
0.8

0.6

0.2

0

1 •

/

1 °—

'

/

m—

/ . •••

it

TIf

0 0.2 0.4 0.6

defbrrr?a/-/on in/8fY

Figure 18.Racking load on wall CQ.

Load-deformation (open circles) and load-set (solid circles) results for specimens CQ-Rl, R2. and RS. The loads are in tips per foot of actual width of specimen. The deformations and sets are for a gage length

of 7 ft IIH in., the gage length of the deformeter.

They are not used in a house. The flanges of adjacent panels enclosed a wood nailing strip, as shown in figure 20. There were nine horizontal slots in each

flange, spaced 1 ft 6 in. on centers and 1^ %2 in. from the web of the panel. The centers of the

end slots were 2^)ii in. from the ends of the

flange. Panels were locked together by Hshaped keys, which were inserted through the

slots, turned 90°, and driven against one end of the slot. The keys were sheet steel. No. 11 U. S. Std. Gage (0.1225 in. thick), plated with

cadmium. The details of the slot and key

connections were the same as in the wall specimens, shown in figures 4 and 5. Nailing strips.—The nailing strips, C, were

yellow poplar, 12 ft 5^%6 in. long, by V/U in., S4S. The strips were enclosed by the flanges

of the floor panels.

Spacer blocks.—The spacer blocks, D, were

yellow poplar, 5%6 in. long, 1% by 2 in., S2S, 13 along each edge of the specimen, spaced 1 ft. on centers. Each block was fastened to the

Figure 19.

Floor specimen CR.

A, full-width floor panels; B, half-width floor panels; C, nailing strips; D, spacer blocks; E,

flooring. edge strip; F, headers; G, subflooring; H, finish

16
web of the half-width panels by one % in. No. 8

self-tapping screw, passing through the web

into the block. Spacer blocks are not used in a house.

Edge strips.—The edge strips, E, were yellow

poplar, 12 ft 5'%, in. long, % by 2 in., S2S, and

were placed over the spacer blocks along each

edge of the specimen to provide continuous

support while the flooring was being laid and

when the specimens were handled. Each strip was fastened to each spacer block by two 7d

cement-coated common nails passing through

the edge strip into the spacer. Before the specimens were tested, the strips were sawed through between adjacent blocks

and therefore had no appreciable effect on the

structural properties of the specimens. Edge

strips are not used in a house.

Headers.—The headers, F, were sheet-steel

channels. No. 20 U. S. Std. Gage (0.0368 in. thick), 4 ft VYie, in. long, Q%2 in. wide, and 2 in. deep. Each was fastened to the floor panels by

No. 8 self-tappmg screws, one to each nailing

stri]) through the ii|)p(>i' llaiigc luid luiic t In

tlie lower flange. EiU!li screw t lii<)ii;/li I lie uj)-

per lliinge was I'/i in. long and j)iissc(l tliroiigli

tiie flange of the header, the niiiling sti-ip, and

the flange (of the door panel) back of tlic luiil- ing strip. Two additioniil No. 8 sci-(!ws passed

through the upper flange of the header, one into

each end spacer block. Each screw through tiie lower flange was % in. long and passed through

tlie flange of the header and the web of a dooi' panel, two of the screws entering the end spacer

blocks and the other two being ecpialiy spaced

between them.

Headers of this type are not used in a house.

Subflooring

.

—The subflooring, G, was southern yellow pine, in. thick by 5%6 in. face

width, and was laid at an angle of about 45°

with the panels. Each piece was fastened to each nailing strip a,nd each edge strip by two

4d cement-coated common nails. Finish flooring.—The finish flooring, H, was

white oak, "^fzi in. thick by 2}^-in. face width.

Each piece was blind-fastened through the subFiGtiRE 20.—Details of floor CR.

A, floor panel; C, nailinp: strip; F, header.

fl71
flooring to each nailing strip and edge strip,

either by one 2-ui. light-gage wire brad or by

one 4d finishing naU.

Paint.—The entire surface of each piece of

steel was covered in the shop with one coat of

primer, applied by spraying, and then baked 1 hour at 200° F.

(6) Comments

Standard floor panels of this construction are 10 in. wide and 6 in. deep, in lengths up to 14

ft. For greater lengths the panels are spliced at midspan. Special sections, varying in both

width and depth, are furnished for unusual

load requhements. No special equipment or

tools are requhed for erection.

The panels are supported by the foundation

wall or by a center girder. The ends are in contact with a continuous angle header, which is coated with asphalt mastic and rests on a strip

of asphalt-impregnated felt. Any conventional

type of flooring may be applied.

2. Transverse Load

The results for floor specimens CR-Tl, T2,

and T3 under transverse load are shown in

table 9 and in figure 21.

/ooo

400

\ 500

\

A 100

0'

\•

era

1 •

\•—

1

1m

1•

1•

i

1 /• P

y

02 0,4 0,6 0.8

def/ec f/on in, Figure 21.—Transverse load on- floor CR.

Load-deflection (open circles) and load-set (solid circles) results for speci- mens CR-Tl, T2, and T3 on the span 12 ft 0 in.

soo

\ 600

I^ 400

I

200

0

1

\

»—

1

o-(

1 °—

1

1 t o-

-o —• • •

1

0-0-, —o

/ o

-o-o~f— —•• • Zy-J- C

1 • •• GD-V

1 • ••

—o-Jo

o

/ -/—o

/ /

CP 0 00£ 004 006 OOS

inc/enfaf/on in, Figure 22.

Concentrated load on floor CR.

Load-indentation (open circles) and load-set (solid circles) results for specimens CR-Pl, P2, and PS.

Table 9.

Structural properties of floor CR

[Weight, 9.911b/ftz]

Transverse load » Concentrated load Impact load "

Specimen

Maxi- mum

load Specimen

Maxi- mum

load Specimen

Maxi- mum

height of drop

Tl

Iblfl'390

376

382

PI b 1, 000

b 1, 000

b 1, 000

n

ftblO.O

b 10.0

b 10.0 n P2 12 T3 PS IS

Average... Average.

.

Average.

.

383 b 1,000 b 10.0

» Span 12 ft 0 in.

b Specimen did not fail. The speed of the movable head of the testing

machine was adjusted to 0.22 in./min.

Under the maximum loads the upper portions

of the flanges of all the floor panels in each of

the specimens budded between the loading

roUers, but the subflooring and finish flooring were undamaged.

3. Concentrated Load

The results for floor specimens CR-Pl,

P2, and PS under concentrated load are shown

in table 9 and in figure 22. The concentrated loads were applied to the

upper face of specimens CR-Pl, P2, and PS

[18]
over an end-matched joint between two finish- flooring strips.

The sets after a load of 1,000 lb had been

applied were 0.021, 0.013, and 0.011 in.,

lespectively, for these specimens, and no other

effect was observed.

4. Impact Load

Floor specimen CR-Il during the impact

test is shown in figure 23. The results for floor specimens CR-Il, 12, and 13 are given in table

9 and in figure 24. The impact loads were applied to the center

of the upper face on the finish flooring directly over the joint between the two fuU-width floor panels. After the 10-lt drop the sets in speci- mens CR-Il, 12, and 13 were 0.022, 0.020, and

0.052 in., respectively, and no other eft'ect was observed.

Figure 23.—Fluor .specimen CR-Il during the impact

test.

0 O.F 0,4 0.6

der/ecf/on in, Figure 24.

Im-pact load on floor CR.

Height of drop-deflection (open circles) and height of drop-set (solid

circles) results for specimens CR-Il, and 13 on the span 12 ft 0 in.

VII. ROOF CS

1. Sponsor's Statement

Roof CS consisted of prefabricated sheetsteel channels joined at the flanges, the webs

formmg the roof deck. The upper face was

insulating board and asphalt roofing, and the

lower was gypsum wallboard. The entu-e sur- face of the steel was covered with paint. The

same size and type of channel-shaped panel was

used in roof CS as in floor CR, but in the roof

construction the lower face of the specimen was

fastened to the flanges of the panels, not the

upper face, as in the floor specimens.

The price of this construction in Washington,

D. C, as of July 1937, was $0.63/ft^

Each roof specimen, as shown in flgure 25, was

14 ft 6 in. long, 4 ft 2 in. wide, and 8 in. thick.

Each consisted of four full-width roof panels,

A; two half-width panels, B; nailing strips, C;

spacer blocks, D; edge strips, E; headers, F;

insulating board, G; roofing, H; and gj^psum

wallboard, /. Rooj panels.—The full-width roof panels, ^1, were sheet-steel channels. No. 18 U. S. Std.

Gage (0.0490 in. thick), 14 ft 5i%6 in. long,

10 in. wide, and 6 in. deep. The half-width

roof panels, B, were the same as one-luilf of a

[19]
full-width panel, A, divided along the longitudinal center line. They are not used in a house. The flanges of adjacent panels enclosed

wood nailing strips, like the floor panels shown

in figure 20. The roof panels were the same as floor panels

except in length. Since the maximum length of panel available in one piece is 14 ft 0 in., the

panels were fabricated of two pieces, each 7 ft 2^j32 in. long, joined at midlength by a sheetsteel splice channel, No. 16 U. S. Std. Gage

(0.0613 in. thick), 36 in. long, shown in figure

26. The splice channel fitted mside the roof

panels and was centered on the joint. Each

splice was fastened by 66 spot welds, in 6 transverse rows of 11 welds each (3 welds in each flange and 5 in the web). The rows were

1, 4, and 12 in. from the joint on each side. There were eight horizontal slots in each

flange, four on each side of the splice, spaced

1 ft 6 in. on centers and P'/32 in. from the web

of the panel. The end slots were respectively,

6 and 9 in., from the ends of the panels. The

panels were locked together b^^ H -shaped keys

which were inserted through the slots, turned

90°, and driven against one end of the slot. The keys were sheet steel. No. 11 U. S. Std.

Gage (0.12^^5 in. thick), plated A\-ith cadmium.

The slot-nnd-key connections were like those

in the wall specimens, shown in figures 4 and 5. The fianges of adjacent panels were also joined

at the splices by two ^s-in. stove bolts, spaced

1 ft 3 in. Each bolt was 1 ft 6 in. from the

nearest slot. Availing strips.—The nailing strips, C, were

yellow poplar, 14 ft o^'^U in. long, -%2 by l^ie in., S4S, and were enclosed by the flanges of the roof

panels.

Spacer blocks. —The spacer blocks, D, were

vellow poplar, o"'ie. in. long, 1^;^ by 2 in., S2S, 15

along each edge of a specimen, spaced 1 ft on

centers. Each block was fastened to the web

of the half-width panels by one ^4-in. No. 8 self- tapping screw, passing through the web into the

block. Spacer blocks are not used in a house.

Edge strips.—The edge strips, il^vere yeUow

poplar, 14 ft 5^^6 in. long, % by 2 in., S2S, and

were placed along the edges of the specimen to provide contmuous support for the wallboard

during nailing and when the specimens were

handled. Each edge strip was fastened to the

spacers by two 7d cement-coated common nails. Before testing the roof specimen, the strips were sawed through between adjacent blocks

and therefore had no appreciable efl'ect on the

structm-al properties of the specimen.

Edge strips are not used in a house.

Headers.—The headers, F, were sheet-steel channels, No. 20 U. S. Std. Gage (0.0368 m.

thick), 4 ft mir, in. long, Qjio in. wide, and 2 in. deep. The upper flange of each header was

fastened to the webs of the panels by four %-Ln. No. 8 self-tapping screws, equally spaced, the ^ screws at the edges entering spacer blocks.

The lower flange was fastened by seven 1/4-in. No. 8 self-tapping screws, one into each edge

strip and one through each nailing strip and

through the flange of a panel back of the nail- ing strip.

Headers of this type are not used in a house.

Insulating board.—The insulating board, G, was 1 in. thick, and consisted of four pieces 4 ft 2 in. vride, three 4 ft 0 in. long and one 2 ft 6 in. long, laid transversely to the panels, the shorter

piece being at one end of the specimen. The

board was fastened to the roof deck (the upper

surface of the webs of the panels) by asphalt

30 Ib/JOO ft-, applied hot by mopping.

Roofing.—The roofing, H, was three-ply

biult-up asphalt-satiirated felt, laid over the in- sulating board. Each strip of felt, 36 in. wide, was laid longitudinaUy of the specimen. The

strips overlapped 25 in. Hot asphalt, temperature not over 400° F, was applied to the surface

of the insulating board, to each strip of felt as it was laid, and finally to the upper surface of the

built-up roof. The amount of asphalt on the insulating

board was 40 Ib/lOO ft^, between the strips of

felt 25/100 ft-, and 40 Ib/lOO ft^ on the buflt-up

roofing.

Gypsum wallboard.—The gypsum waflboard,

/, was ]i m. thick and consisted of four pieces

4 ft 2 in. ^\-ide, three of them 4 ft 0 in. long and

one piece 2 ft 6 m. long, the shorter piece being

at one end of the specimen. The waUboard

was fastened transversely to the roof panels by

a row of 1-in. plasterboard nafls, four into each

nailmg strip and edge strip through the longer

pieces and tliree into each strip through the

shorter piece. The joints in the waUboard were

neither calked nor reinforced.

[20]

Paint.—The entire surface of eacli piece of

steel was covered, in the shop with one coat of

primer, appHed by spraying, and then baked

1 hour at 200° F.

2. Transverse Load

Roof specimen CS-Tl under transverse load

is shown in figure 27. The results for roof

specimens CS-Tl, T2, and T3 are presented in

table 10 and in figm-e 28.

Table 10.

Structural properties of roof CS

[Weight, 11.91b/ft2]

Transverse load* Concentrated load

Specimen Maximum

load Specimen Maximum

load

Tl

Iblft 2170 172

150

PI

lb b 1, 000

b 1. 000

b 1,000 T2 PB

TS PS

Average __ .. 164 b 1. 000

"Span 14 ft Gin.

b Specimen did not fail

The speed of the movable head of the testing

machine was adjusted to 0.29 in./min.

Under the maximum load on each specimen

the webs and flanges of all the panels budded

between the loading rollers, but not in the

splice. The wallboard on the lower face was

undamaged.

-Si 80

40*

0'

» c 09 -co

/ —CQ^—

a

/

/•

•

•

CS 0 02 0,4 06 08

def/ecf/'on in, Figure 28.—Transverse load on roof CS.

Load-deflection (open circles) and load-set (solid circles) results for speci- mens CS-Tl, T2, and TS on the span 14 ft 0 in.

/OOO

5J

800

600

400

200

0

1—• * /

c»-jf> ( —

/ • • o<

1 / /

/

» • <XrO-

' /

•• h-OKD /

7/

\J

CS

Figure 27.

Uoof s-pecimen CS~Tl under tranvserse load.

0 05 /.O 1.5 /nc/enfa//on /n. Figure 29.

Concentrated load on roof CS.

Load-indentation (open circles) and load-set (solid circles) results for specimens CS-Pl, P2, and PS.

[22]
FiGUHE 30

Typical details of "ScotBilt" construction for houses. n

r

3. Concentrated Load

Resiilts for roof specimens CS-Pl, P2, and

PS under concentrated load are shown in table

10 and in figure 29. The loads were applied to the upper face on

the asphalt roofing midway between the flanges

of a panel and about 1 )i ft from one end of the

specimen. To obtaia reproducible results each

load was applied for 30 sec before reading the

micrometers, and the set readings were taken

30 sec after release of the load.

The disk punched through the outer covering

of asphalt and insulating board on each speci- men. After a load of 1,000 lb had been applied

to specunens CS-Pl , P"2, and PS, the sets were

0.98, 1.39, and 0.84 in., respectively, and no

other effect was observed.

VIII. ADDITIONAL COMMENTS BY

SPONSOR

Thirteen commercial buildings and one dwellmg have been constructed of "Scot-BUt"

prefabricated units. Either mineral wool or

reflectuig metal sheets were used as thermal

insulation.

Typical details of a house of this construction are shown in figure 30. Floor panels are not required if the floors are concrete. If there is no basement, a reinforced concrete

slab serves as both foimdation and fu-st floor. The roof in all cases is of the flat type and is supported by 3- by 3-in. shelf angles screwed

to the wall and partition panels. The wall

panels extend above the roof on all sides

except one, which is left open for run-off. On

[23]
the closed sides the roofing extends up along

the inside of the wall panels and is overlapped

by the continuous sheet-steel coping, No. 18

U. S. Std. Gage, which covers the tops of the

wall panels. On the open side the roofing is extended down into a sheet-metal hanging

gutter.

Both floor and roof panels may be erected

with the flanges either up or down. If wallboard or plaster is used for ceiling finish, the

flanges are turned down.

The interior waU finish consists of sheetsteel panels, wallboard, or plaster. Wallboard or lath is nailed to the wood strips over waterproof paper.

Load-bearing partitions are assembled from

prefabricated sheet-steel wall panels. Nonload-bearing partitions consist of fidl-size pre- fabricated sheet-steel units. Pipes, ducts, and

conduits are placed in the cavities of waUs,

floors, and partitions.

Chimneys are of brick with tile flue linings.

Two-story buildings can be constructed by

splicing the wall panels and supporting the

second-story floor on shelf angles in the same manner as the roof.

The descriptions and drawings of the speci- mens were prepared by E. J. Schell, G. W.

Shaw, and T. J. Hanley of the Building Practice and Specifications Section of this Bureau,

under the supervision of V. B. Phelan.

The structural properties were determined

by the Engineering Mechanics Section, under

the supervision of H. L. ^Vhittemore and A. H.

Stang, with the assistance of the following

members of the professional stafl': F. Cardile,

H. DoUar, M. Dubin, A. H. Easton, A. S. Endler, A. B. Lanham, A. J. Sussman, and L. R.

Sweetman.

Washington, December 2, 1939.

[24]
BUILDING MATERIALS AND STRUCTURES REPORTS

On request, the Superintendent of Documents, U. S. Government Printing Office, Washington, D. C, will place your name on a special mailing list to receive notices of new reports in this series as soon as they are issued. There will be no charge for receiving such notices. An alternative method is to deposit with the Superintendent of Documents the sum of $5, with the request that the reports be sent to you as soon as issued, and that the cost thereof be charged against your deposit. This will provide for the mailing of the publications without

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If 100 copies or more of any paper are ordered at one time, a discount of 25 percent is allowed. Send all orders and remittances to the Superintendent of Documents, U. S. Government Printing

Office, Washington, D. C.

The following publications in this series are available by purchase from the

Superintendent of Documents at the prices indicated:

BMSl Research on Building Materials and Structures for Use in Low-Cost Housing 10^ BMS2 Methods of Determining the Structural Properties of Low-Cost House Constructions.. 10^ BMS3 Suitability of Fiber Insulating Lath as a Plaster Base 10^ BMS4 Accelerated Aging of Fiber Building Boards 10^ BMS5 Structural Properties of Six Masonry Wall Constructions 15^ BMS6 Survey of Roofing Materials in the Southeastern States 15^ BMS7 Water Permeability of Masonry Walls 10^ BMS8 Methods of Investigation of Surface Treatment for Corrosion Protection of Steel 10^ BMS9 Structural Properties of the Insulated Steel Construction Co.'s "Frameless-Steel"

Constructions for Walls, Partitions, Floors, and Roofs 10^ BMSIO Structural Properties of One of the "Keystone Beam Steel Floor" Constructions Sponsored by the H. H. Robertson Co 10^ BMSll Structural Properties of the Curren Fabrihome Corporation's "Fabrihome" Constructions for Walls and Partitions 10^ BMS12 Structural Properties of "Steelox" Constructions for Walls, Partitions, Floors, and Roofs

Sponsored by Steel Buildings, Inc 15^ BMS13 Properties of Some Fiber Building Boards of Current Manufacture 10^ BMS14 Indentation and Recovery of Low-Cost Floor Coverings 10f5 BMS15 Structural Properties of "Wheeling Long-Span Steel Floor" Construction Sponsored by

the Wheeling Corrugating Co 10^ BMS16 Structural Properties of a "Tilecrete" Floor Construction Sponsored by Tileerete Floors, Inc 10^ BMS17 Sound Insulation of Wall and Floor Constructions 10^ BMS18 Structural Properties of "Pre-Fab" Constructions for Walls, Partitions, and Floors Sponsored by the Harnischfeger Corporation 10^ JBMS19 Preparation and Revision of Building Codes 15^ BMS20 Structural Properties of "Twachtman" Constructions for WaUs and Floors Sponsored by

Connecticut Pre-Cast Buildings Corporation lOfi BMS21 Structural Properties of a Concrete-Block Cavity-Wall Construction Sponsored by the National Concrete Masonry Association 10^ BMS22 Structural Properties of "Dun-Ti-Stone" Wall Construction Sponsored by the W. E. Dunn Manufacturing Co 10^ BMS23 Structural Properties of a Brick Cavity-Wall Construction Sponsored by the Brick

Manufacturers Association of New York, Inc 10^ BMS24 Structural Properties of a Reinforced-Brick Wall Construction and a Brick-Tile CavityWall Construction Sponsored by the Structural Clay Products Institute 10^ BMS25 Structural Properties of Conventional Wood-Frame Constructions for WaUs, Partitions,

Floors, and Roofs 15^ BMS26 Structural Properties of "Nelson Pre-Cast Concrete Foundation" Wall Construction

Sponsored by the Nelson Cement Stone Co., Inc 10^ BMS27 Structural Properties of "Bender Steel Home" Wall Construction Sponsored by The

Bender Body Co 10^ BMS28 Backflow Prevention in Over-Rim Water Supplies 10^ BMS29 Survey of Roofing Materials in the Northeastern States 10^ BMS30 Structural Properties of a Wood-Frame Wall Construction Sponsored by the Douglas

Fir Plywood Association 10^ BMS31 Structural Properties of "Insulite" Wall and "InsuHte" Partition Constructions Sponsored by The Insulite Co 15^ BMS32 Structural Properties of Two Brick-Concrete-Block Wall Constructions and a Concrete- Block Wall Construction Sponsored by the National Concrete Masonry Association. . 10^

[List continued on cover page iv]
BUILDING MATERIALS AND STRUCTURES REPORTS

[ Continued from cover page iii ] BMS33 Plastic Calking Materials 10^ BMS34 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 1 10^ BMS35 Stability of Sheathing Papers as Determined by Accelerated Aging 10^ BMS36 Structural Properties of Wood-Frame Wall, Partition, Floor, and Roof Constructions

With "Red Stripe" Lath Sponsored by T?he Weston Paper and Manufacturing Co-_ 10^ BMS37 Structural Properties of "Palisade Homes" Constructions for Walls, Partitions, and

Floors Sponsored by Palisade Homes 10(i BMS38 Structural Properties of Two "Dunstone" Wall Constructions Sponsored by the W. E. Dunn Manufacturing Co 10^ BMS39 Structural Properties of a Wall Construction of "Pfeifer Units" Sponsored by the Wisconsin Units Co 10(i BMS40 Structural Properties of a Wall Construction of "Knap Concrete Wall Units" Sponsored

by Knap America Inc 10(t BMS41 Effect of Heating and Cooling on the Permeability of Masonry Walls lOji BMS42 Structural Properties of Wood-Frame Wall and Partition Constructions With "Celotex"

Insulating Boards Sponsored by The Celotex Corporation 10^ BMS43 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 2 10^ BMS44 Surface Treatment of Steel Prior to Painting 10^ BMS45 Air Infiltration Through Windows 10^ BMS46 Structural Properties of "Scot-Bilt" Prefabricated Sheet-Steel Constructions for Walls,

Floors, and Roofs Sponsored by The Globe-Wernicke Co 10^