I
The program of Research on Building Materials and Structures carried on by the

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

housing construction and finance, which is cooperating in the investigations through a committee of principal technicians.

CENTRAL HOUSING COMMITTEE

ON RESEARCH, DESIGN, AND CONSTRUCTION

Htjgh L. Deyden, Chairman. Howard P. Vermilya, Vice Chairman.

National Bureau of Standards. Federal Housing Administration.

Vincent B. Phelan, Secretary.

Mary F. Taylor : Assistant Secretaries : Louise D. Card

Tirrell J. Ferrenz, John F. Donovan,

Federal Home Loan Bank Board. Farm Security Administration.

A. C. Shire, George W. Trayer,

United States Housing Authority. Forest Service (F. P. Laboratory).

Warren G. Noll, Rollo H. Britten,

Public Buildings Administration. Public Health Service.

Luther M. Leisenring, George E. Knox,

Construction Division (War). Yards and Docks (Navy).

Edward A. Poynton, William R. Talbott,

Office of Indian Affairs. Veterans' Administration.

Wallace Ashby,

Bureau of Agricultural Chemistry and Engineering.

NATIONAL BUREAU OF STANDARDS

STAFF COMMITTEE ON ADMINISTRATION AND COORDINATION

Hugh L. Dryden, Chairman.

Mechanics and Soimd.

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 Forest Service is cooperating with both

committees on investigations of wood constructions.

[For list of BMS publications and directions for purchasing, see cover page III.]
UNITED STATES DEPARTMENT OF COMMERCE • Jesse H. Jones, Sccrcrary

NATIONAL BUREAU OF STANDARDS • Lyman J. Briggs, Director

BUILDING MATERIALS

and STRUCTURES

REPORT BMS80

Performance Test of Floor Coverings for Use

in Low-Cost Housing: Part 4

by PERCY A. SIGLER and ELMER A. KOERNER

ISSUED MARCH 2, 1942

The National Bureau di Standards is a tact-iinding organization;

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

UNITED STATES GOVERNMENT PRINTING OFFICE • WASHINGTON • I942

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

In order to obtain technical information and data on the relative ability of different

types of floor coverings to withstand service, laboratory performance tests have been

conducted at the National Bureau of Standards as part of a research program on building

materials suitable for low-cost house constructioii. These performance tests have given

information on the resistances of the floor cover to abrasion, indentation, and fracturing.

This report presents the results of a test on a fourth series of 40 floor-covering

mstallations in the Bureau's floor-testing chamber, as a supplement to reports BMS34,

BMS43, and BMS68. Photographs of the floor coverings, taken at the end of the test, are shown, and brief summaries of the manner m which the various installations performed

are presented.

Lyman J. Briggs, Director.

[Ill
Performance Test of Floor Coverings for Use in

Low-Cost Housing: Part 4

by Percy A. Sigler and Elmer A. Koerner

CO NT

Page Foreword ii

I. Introduction 1

II. Floor-testing chamber, equipment, and

procedure 2

III. Description of test installations 3 IV. Results 3

V. Summarj', and discussion of results 5

1. Cork titles 5

2. Rubber tile 5

3. Asphalt tile 5

4. Linoleums 5

5. Felt-backed floor coverings with

wearing surfaces 5

(a) Marbleized linoleum composition 5

(b) Cellulose nitrate composition 5

ENTS

Page V. Summary, and discussion of results

Continued.

5. Felt-backed floor coverings with

wearing surfaces—Continued.

(c) Asphalt composition 5

(d) Enamel 5

(e) Resin-treated cotton-linters sheet 20

6. Cotton duck 20

7. Maple and pecan unit-blocks 20

8. Strip maple 20

9. Asphalt and coal-tar mastics 20

10. Alumina cement-rubber latex composition 20

11. Magnesium oxychloride composition 20

12. Portland cement concrete 20

VI. Recommendations and conclusions 21

ABSTRACT

A performance test was conducted in the floor-testing

chamber of the National Bureau of Standards on a

fourth series of 40 different installations involving 26

different floor coverings. Specimens of most of the

floor coverings were installed on both a concrete and a wood subfloor. Included in the test were cork tiles, rubber tile containing aluminum oxide aggregate,

asphalt tile, marbleized linoleums, felt-backed floor coverings having various wearing surfaces, strip maples,

maple unit-block, pecan unit-block, asphalt mastic,

coal-tar mastic, alumina cement-rubber latex composition, magnesium oxychloride composition, and 1:2:4 Portland cement concrete. Different underlays and

adhesives were also included in the test. The test installations are described and results showing the depth of the depressions in the floor coverings made by

the equipment are presented in tables. Brief summaries

of the manner in which the various installations per- formed are given, and their appearance at the end of the test is shown by photographs. A few generalized

comments and conclusions are made.

I. INTRODUCTION

Laboratory performance tests of floor coverings installed in various ways have been con- ducted at the National Bureau of Standards

to determine their relative ability to withstand severe treatments. The results may be

used as a guide for predicting their probable

performance in service. This report presents

the results obtained on a fourth series of

installations and supplements the published

reports on the three previous series in BMS34,

BMS43, and BMS68 (see cover page 3). In a laboratory performance test it is possible

to include and control many of the factors

affecting performance and durability in service.

However, it was not found possible to include

all such factors in an accelerated test. No

attempt, for example, was made to ascertain

the effects of the periodic use of cleansing

agents, the periodic application of protective

coatings, or age. Other laboratory investigations have been

conducted on various floor coverings and adhesives to determine their relative merits with

respect to specific properties. The results of some of these investigations have been published

BMS14, BMS59, and BMS73 (see cover page 3).

[1]
II. FLOOR-TESTING CHAMBER, EQUIPMENT, AND PROCEDURE

The Bureau's floor-testing chamber provided

a concrete circular track 4 feet wide and approximately 40 feet in diameter. The track was

divided into 40 test spaces, 3 feet long. Concrete or strip-wood subfloors and the various

floor coverings were installed in these spaces. The concrete subfloors had a steel-troweled

Figure 1.

Testing equipineni

finish. The strip-wood subfloors were blindnailed with 8d cut nails to foiu' wooden sleepers

spaced 12 inches on centers. The sleepers were

approximately parallel to the direction of travel

of the testing equipment and were embedded

in concrete. Since the equipment and procedure used in

making this performance test have been fully

described in previously published reports,

BMS43 and BMS68, they are only briefly

presented here. Figure 1 shows the testing

equipment and a portion of the circular track. The test consisted in subjecting the floor coverings to 48,000 cycles, or passages, of a

two-wheeled platform truck, a "walking wheel"

4 feet in diameter, and two casters. The truck

carried a total load of approximately 1,100

pounds and was equipped with a steel-tired

wheel and a rubber-tired wheel. The walkingwheel carried a load of approximately 275

pounds and was shod with eight wooden blocks

covered with leather during the first half of the

test and with No. 3 grit garnet cloth during the

second half of the test.

ind portion of circular track.

The two casters, attached to lever mechanisms mounted on the front of the tnick, consisted of a 2-inch steel wheel with a %-inch face

loaded to 20 pounds and a 1-inch steel ball loaded to 10 poimds. The equipment was

pushed around the track by the walking wheel

at about 2 miles an hour. A dial depth gage was used to measure the depressions made in the floor coverings by the equipment. During

the test the floor coverings were swept at least once a day to remove loose particles. At the

end of the test the floor coverings were washed

with soap and watei' and then photographed.

[2]
III. DESCRIPTION OF TEST

INSTALLATIONS

Twenty-six different floor coverings and 10

different adhesives wore included in this per- formance test. With a few exceptions, speci- mens of each floor covering were installed on both a concrete and a wood subfloor. A

detailed outline of the 40 test instuUutioiis is given in table 1.IV. RESULTS

The average depths of tin; depressions in the

floor coverings made by the two ti'iick wheels

and the walking wheel, at didVicnt stages of the performance test, are recorded in liddc 1.

Table 1.—Test installations and results of measurements for depth of compression and wear

Subfloor

Concretestrip-wood ' Concrete ...do

Strip-wood Concrete

Strip-wood ' Concrete

strip-wood ' Concrete

strip-wood ' ....do.-

....do.' Concrete

Strip-wood ' Concrete

Strip-wood ' Concrete

Strip-wood ' Concrete

Strip-wood ' Concrete

strip-wood ' .._.do.'

.do.'

-do.'

Concrete.

----do--..

----do Strip-wood ' Concrete

----do.e Wood sleepers.-.

--..do

Concrete

strip-wood

Gypsum mortar

Underlay

None.

Lining felt None

....do Lining felt None

LininR felt

'

None

Lining felt None

Joining felt ----do,<J None

- ..do

-do.

-do-

--.do-

...do.

-do.

-do.

--.-do-...

- -do---- Plywood

...do.i--

Lining felt i. None

-do- -do-

----do---- Plywood ' None

.do-

-do-

-do-

-do-

-do-

- doBonding agent

Lignin paste

-

.do- Copal resin cement.

----do

----do Lignin paste-

-do-

."Vsphalt emulsion, clay type. ----do Lignin paste ----do .---dodo

----do

-do- Cumar resin cement-

. -do Lignin pastS-

-do -do

-do-

-do-

-do-

-do-

-do-

-do-

-do-

-do-

----do

- -.do Cut-back asphalt. Warm asphalt

Blind-nailed. 6d .screw

nails, Blind-nailed, 8d cutnails, Asphalt emulsion, clay type.

-do.

Floor covering as in- stalled.

Floor covering

Type and description '

Cork tile i^; high density; lacquer

finish. --..do.b Cork tile >>; dark shade; factory- applied varnish finish. Cork tile light shade; factory- applied varnish finish.

- (l(),i< Rubber tile >>; black; contained aluminum oxide aggregate.

..--do.i' Asphalt tile ''; black

.-..do.b Marbleizcd linoleum; brown

do

do

--...do Felt-backed; blue; wearing surface, marbleized linoleum

composition.

----do Felt-backed tile h; mahogany;

wearing surface, marbleized

linoleum composition.

.--.do,i' !• Felt-backed tile ij; maroon; wearing surface, cellulose nitrate composition.

.---do.>> Felt base; black; corrugated wearing surface, asphalt composition. ...-do ----do ---do

Felt base; red; wearing surface, enamel.

--.do

Felt base; brown; wearing surface, varnish over enamel.

...-do-- -..„ Felt-backed; gray; wearing surface, resin-treated cotton-linters sheet. No, 4 cotton duck k; green

. -dct

-Vtaple unit-block i>m; flat back; metal splines at ends. Pecan unit-block i> »>; hollow

back: wood splines at ends.

strip Northern hard maple "i; first grade; flat back.

strip Southern hard maple ">; first grade; flat back. Asphalt mastic composition; dark gray; aggregate, burned

volcanic ash and Portland cement. Asphalt mastic composition;

red; aggregate, burned vol- canic ash and Portland cement.

Coal-tar mastic composition

gray; aggregate, gravel, sand and gypsum.

Average depth of depression made by

Rubber- Steel- tired tired Walking

"Nomi- truck truck wheel

nal wheel wheel

hick- ness

10, 000 48, 000 10, 000 48, 000 24, 000 48, 000

cycles cycles cycles cycles cycles cycles

in. in. in. in. in. in. in. Ha 0. 000 0. 002 0. 003 0. 010 0. 001 0. 008 Mo . 001 . 002 . 003 . 009 . 001 .016 Mg .002 .005 .006 .015 .003 .029 Mo . 003 . 007 .008 .016 .003 .014 uri .002 .012 .007 .022 .003 .022

.001 .001 .004 .008 .001 .010

.000 .001 . 010 . 016 . 005 . 009

(') (') .004 .007 .006 .012

. 004 . 007 .009 (-) .002 .010 %i .001 .001 . 001 . 009 . 000 .002

. 001 . 002 .009 .0.33 .005 .006

.001 .002 . 005 . 012 . 005 . 007

. 001 . 001 (") .002 .005

34., 7 j2 .000 .001 .005 .018 .001 .002

%2 .002 .002 .017 ((.) . 003 004

7*3 2 . 000 . 000 .005 .010 !ooo !002

%2 .000 .001 .005 («) .001 .003 %2 .000 .000 . 004 . 015 . 001 . 002

. 001 . 002 .010 .033 .002 .003 %4 .001 .007 .011 .039 .003 .018

Hi .002 .004 .007 .025 .006 .024

.001 .002 .010 .031 .om .016 Hi .002 .006 .008 .016 .004 .020 Me .004 .004 .008 ("^ .003 . 008 Mo .009 .010 .018 .026 .008 .014 Hi .002 .002 .013 (') .002 (') Hi .000 .001 .005 .015 .000 .008 Mo .000 .002 .000 .015 .001 .005

Hi .000 .002 .001 .013 .001 .006

'Hi .001 .002 .012 .039 .002 .006

25/32 (') (0 .002 .010 .001 .004

(0 (') .002 .012 .001 .007 m2 .001 .002 .005 .018 .000 .002

25^2 .000 .001 .003 .015 .001 .002 H .001 .010 .033 .117 .006 .045

H .002

.003 .090 .006 .038

See footnotes at end of table.

[3]
Table 1. —Test installations and results of measurements for depth of compression and wear—Continued

Test

panel Subfloor Underlay Bonding agent

Floor covering Average depth of depression made by

Type and description » Nominal

thick- ness

Rubbertired truck wheel

Steel- tired truck wheel

Walking

wheel

10. 000

cycles

48, 000 cycles10, 000

cycles

48, 000

cycles

24, 000

cycles

48, 000

cycles

37

8....

39....

iO..,.

Concrete

Strip-wood

None

do

Floor covering as in. stalled. do

Alumina cement-rubber latex composition; red; aggregate, marble chips. Alumina cement-rubber late.x

Vi

Vi

H

4

ixi 0. 001

.001

.000

.000

0.002

.002

.000

.001

ill. 0. 010

.010

.001

.006

0.o'2'2

.021

.007

.025

o.o'os

.002

.000

.000

0.030

.020

.006

.025

Concrete »- . --. do do

composition reinforced with expanded metal lath; red; ag- gregate, marble chips. Magnesium oxychloride composition; natural gray; aggregate, granite chips and granite

dust.

1:2:4 portland-eement concrete; aggregate, Potomac-river sand and gravel; interval between

placing and troweling, 3 hr.; damp-cured for 6 days.

» Color listed is the predominating color,

b Si2e, 9 by !) in,

« Edge-grained Douglas fir, 25-^2 in, thick, with a 234-in, face.

<i IH lb/yd 2 asphalt-saturated lining felt bonded to subfloor with lignin

paste.

<^ Subfloor given a priming coat of cut-back asphalt,

' Accuracy of measurements was questionable owing to slight curling,

or warping, of floor,

s Floor covering was too severely damaged to measure accurately.

h Back of tile had a factory-applied skim coat of cumar resin cement.

i Three plies of hardwood veneer with asphalt-saturated paper on both

faces. Thickness, Ms in, Fastened to subfloor with screw-nails.

' ?4 lb/yd ' dry lining felt bonded to subfloor with lignin paste.

^ Furnished by the U, S, Department of Agriculture. Duck had been

given fireprooflng and waterproofing treatments.

' Douglas-fir plywood, H in, thick, 5-ply. Surface given 1 heavy coat of a sealer."

" Mortar fill of 1 part of gypsum and 2 parts of sand, ^4 in, thick, over

concrete and sleepers. Surface given a priming coat of cut-back coal tar.

0 Floor covering installed at 10,000 cycles to replace panel $6A and thus exposed to a total of only 38,000 cycles.

p Steel-troweled surface of subfloor thoroughly chipped and primed

with magnesium chloride solution.

It is of general interest to note the marked

differences in the depressions and fractures

caused by the two truck wheels. The steel- tired truck wheel damaged many of the floor coverings to an appreciable degree, whereas the

rubber-tired truck wheel did very little damage.

Also of interest is the tendency of most of the

floor coverings to show greater depressions and

fractures on wood subfloors than on concrete

subfloors. These generalizations also apply to most of the installations previously tested. The walking wheel surfaced with leather

caused very little wear for the first 24,000 cycles.

The small depressions appeared to result principally from compression. The average amount

each floor covering was worn by 24,000 cycles

of the walking wheel surfaced with abrasive

cloth is shown in table 2. These values are the over-all averages, computed from the differ- ences in the results at 24,000 and 48,000 cycles

given in table 1, for each floor covering listed,

irrespective of subfloor.

Figures 2 to 42 show the general condition of

the floor coverings at the end of the test. The

five paths shown, and labeled in figure 2, are, from left to right, those made by the rubbertired truck wheel, ET; the steel-ball caster,

SB\ the walking wheel, WW; the steel-wheel

caster, SW; and the steel-tired truck wheel, ST.

The small white dots in the photographs are reference marks used in taking the depth

measurements.

Table 2.

Average wear of floor coverings caused by

24,000 cycles of the "walking wheel" surfaced with

abrasive cloth

Floor coverings '

Cork tile; Me in.; high density Cork tile; Me in.; dark shade Cork tile; Me in.; light shade Cork tile; Vi in.; light shade Rubber tile; \i in.; black r Asphalt tile; 54 in.; black Marbleized linoleum; %2 in.; brown

Marbleized linoleum; Mi in.; brown

Felt-backed; 5^2 in.; blue; wearing surface, linoleum composition. Felt-backed tile; %2 in.; mahogany; wearing surface, linoleum

composition

Felt-backed tile; ?^2 in.; maroon; wearing surface, cellulose nitrate composition

Felt Ijase; Hi in.; black; wearing surface, asphalt composition.

Felt base; =B4 in.; black; wearing surface, asphalt composition.

Felt base; Me in.; red; wearing surface, enamel

Felt base; %i in.; brown; wearing surface, varnish over enamel.

Felt-backed; He in.; gray; wearing surface, resin-treated

cotton-linters sheet Cotton duck; Hi in.; green Maple unit-block; mi in Pecan unit-block; in Strip northern maple; 25-52 in... Strip southern maple; ''Hi in Asphalt mastic composition; \i in.; dark gray

Coal-tar mastic composition; H in.; gray Alumina cement-rubber latex composition; H in.; red Magnesium oxychloride composition; H in.; natural gray

1:2:4 portland-cement concrete; 4 in

" The relative value of a floor covering should not be based entirely on resistance to wear. Other factors should also be considered, such as

cost, indentation characteristics, ease of maintenance, adherence to subfloors, resistance to tear and fracture, etc.

•> See table 1 for detailed description.

[4]
V. SUMMARY, AND DISCUSSION OF

RESULTS

Brief summaries of the manner in which the

various test installations performed are herewith presented.

1. Cork Tiles

The cork tiles as a whole showed good per- formance (see figs. 2, 3, 4, 5, and 6), with the

probable exception of their resistance to abrasion (see table 2). There were no failures in

bond or fractures along any of the paths. The

high-density tile and the light-shade tiles showed

better resistance to abrasion than the darkshade tile. The lacquer finish on the highdensity tile appeared slightly more durable than

the varnish finish on the other tiles.

2. Rubber Tile

The }8-in. rubber tile containing an abrasive

aggregate showed good performance (see figs. 7 and 8). Although some failure in bond oc- curred along the path of the steel-tired truck

wheel, there were only a few fi'actures. The

tile showed good resistance to abrasion.

3. Asphalt Tile

The ji-in. asphalt tile gave good performance on a concrete subfloor but very poor perform- ance on a strip-wood subfloor (see figs. 9 and

10). On a concrete subfloor there were no

failures in bond or fractures along any of the

paths. On a strip-wood subfloor with an underlay of saturated felt the tile was badly broken

and crushed by the steel-tired truck wheel and was also fractured to a considerable extent by the walking wheel. The tile was not

appreciably worn by the abrasive action of the

walking wheel (see table 2).

4. Linoleums

The /32-in. and %4-in. marbleized linoleums

performed well except along the path of the

steel-tired truck wheel, where failures in bond

and fractures occurred in different amounts for the several panels (see figs. 11, 12, 13, and 14).

A comparison of figures 13 and 14 demonstrates

the advisability of using a lining felt with lino- leum on strip-wood subfloors. Where no lining

felt was used failures in bond and fractures

occuiTcd at an early stage of the test (sMt, fig. 14). The marbleized linoleums showed veiy

good resistance to abrasion (see table 2).

5. Felt-Backko P^loor Coverings With

Weaiung Surfaces

(a) Marbleized Linoleum ( '(>m])<>Hiti(>n The %2-in. felt-backed floor coverings in sheet and tile form having an available wearing

surface of marbleized linoleum composition

approximately 0.045 in. thick performed much

better on concrete subfloors than when bonded

direct to strip-wood subfloors (see figs. 15, 16,

17, and 18). The wearing surfaces showed very

good resistance to abrasion (see table 2).

(6) Cellulose Nitrate ('oin]>(>.ntion

The %2-in. felt-backed tile with an available

wearing surface of cellulose nitrate composition

approximately 0.045 in. thick also performed

much better on a concrete subfloor than when

bonded direct to a strip-wood subfloor (see figs.

19 and 20). Impressions of the strip-wood

subfloor were plainly visible on the surface of the floor covering. The tile showed very good

resistance to abrasion (see table 2).

(c) Asphalt Composition.

The felt-base floor coverings having a cor- rugated wearing surface of asphalt composition

performed unsatisfactorily (see figs. 21, 22, 23,

and 24). The wearing surface was pitted and

excessively compressed or pushed to the side by

the steel-tired truck wheel. One of the floor coverings was also grooved considerably by the

two casters. Furthermore, the corrugated wear

ing surfaces did not show good resistance to abrasion (see table 2). A plywood underlay

materially improved the evenness and thus the

appearance of thin floor coverings over stripwood subfloors (compare figs. 22 and 24).

(d) Enamel

The felt-base floor coverings with an enamel

wearing surface approximatel_v 0.005 in. thick were in unserviceable condition at the end of the

test (see figs. 25, 26, 27, and 28). However,

taking into consideration the thinness of the

[S]


[8]
[91
Figure 14.

%,i-in. marhleized linoleum cemented direct to drip-wood suhfloor

(test -panel IS).

Figure 15. — felt-backed floor covering, with wearing surface of marhleized linoleum, com,position, on

concrete suhfloor [test panel 14)

Figure 16. —ji^-in. felt-backed floor cov- ering, with ivearing surface of marbleized linoleum composition, cemented

direct to strip-wood suhfloor {test panel

15).

[10]
Figure 17. — felt-hacked tile, with wearing surface of marhleized linoleum

composition, on concrete subfloor {test

panel 16).

FiGURE 18.

Yii-in. felt-hacked tile, ivith wearing surface of marhleized linoleum

composition, cemented direct to slrip- tvood subfloor {test panel 17).

Figure 19. — Yn-in. felt-hacked tile, with

loearing surface of cellulose nitrate composition, on concrete suhjloor {test panel 18).

[11]
Figure 20. —%2-in. felt-backed tile, with wearing surface of cellulose nitrate composition, cemented direct to strip- wood subfloor (test panel 1.9).

GURE 21. — Yi4-in. felt-base floor covering, with corrugated wearing surface

of asphnli corn position, on con crete subfloor {te.'st panel 20).

Figure 22. — %i-in. felt-base floor cover-

- ing, with corrugated wearing surface

of asphalt composition, cemented direct

to strip-wood subfloor {test panel 21).

[12]
Figure 23.~f24-w. felt-base floor cover- ing, with corrugated wearing surface

of asphalt composition, on concrete sub-- floor {test panel 22).

Figure 24.— felt-base floor cooer- ing, with corrugated wearing surface

of asphalt composition, on plywood

underlay and strip-wood subfloor (test panel 23).

Figure 25.— M«-*". felt-base floor covering, with wearing surface of enamel, on

plyiDood underlay and strip-ivood subfloor [test panel 24).

[13]
Figure 27. —Va-in. felt-base floor covering, ipith 'wearing surface of varnish

over enamel, cemented direct to strip- wnod snhfloor (test panel 26).

Figure 28.

Yn-in. felt-base floor covering, with wearing surface of varnish

over enam,el, on concrete subfloor (test panel 27).

[14]
PiGURE 31.

Yn-in. cotton duck on plij- wood underlay and strip-wood suhfloor

{test panel 30).

[15]
Figure 32. — -^^2-«w. maple unit-block on

coniccte subfloor (test panel 31).

Figure 33.

^Ysi-in. pecan unit-block on

concrete subfloor (test panel 32).

Figure 34.

-%2-in. strip northern maple

on, wood sleepers (test panel 33).

[16]
[17]
[18]

available wearing surface, their low initial cost, and the type of service for which they are designed, their performance was fair. These

floor coverings were severely damaged by the

steel-tired truck wheel, but the rubber-tired

truck wheel caused very little damage. The

enamel coatings were worn through in spots by

the walking wheel in approximately 31,000

cycles, or 7,000 cycles after the wheel had

been covered with abrasive cloth. A comparison of figures 25, 26, and 27 presents additional

evidence of the improvements in evenness and

distribution of wear when an underlay of plywood or felt is used with felt-base floor coverings over strip- wood subfloors.

(e) Resin-Treated Cotton -Linters Sheet

The Ke-in. felt-backed floor covering with a wearing surface consisting of a resin-treated

cotton-linters sheet approximatelv 0.015 in. thick withstood the test fairly well (see fig. 29).

There was some failure in bond to the concrete

subfloor and some fracturing of the floor covering. The wearing surface showed good resist- ance to abrasion (see table 2).

6. Cotton Duck

The cotton (hick performed well with respect

to tearing or fracturing and resistance to abrasion (see figs. 30 and 31, and table 2). On a concrete subfloor there was considerable failure in bond. On Yi-m. Douglas-fir plywood the

depth of the path made by the steel-tireil truck

wheel was appreciable. The cotton duck

accumulated dirt and became badly soiled. It would be difficidt to keep clean.

7. Maple and Pecan Unit-Blocks

The maple unit-block and the pecan unitblock gave very good preformance (see figs.

32 and 33). There was very little evidence of damage along any of the paths. The maple

showed slightly better resistance to abrasion

than the pecan (see table 2).

8. Strip Maple

It would be difficidt to distinguish between

the performance of the strip northern maple

and that of the strip southern maple, both

performed very well and showed very good

resistance to abrasion (see figs. 34 and 35, and

table 2).

9. Asphalt and Coal-Tar Mastics

The asphalt mastic floors and the coal-tar

mastic floor did not perform well in this test. The asphalt mastic on a concrete subfloor was

compressed and grooved to a considerable extent by the steel-tired truck wheel and the steel- wheel caster (see fig. 36 and table 1). The

asphalt mastic on a strip-wood subfloor was so badly damaged that it was necessary to remove

it at 10,000 cycles in order to continue the test

(see fig. 37) . The coal-tar mastic on a gypsummortar subfloor was excessively pitted and

grooved by the steel-tired truck wheel and the

steel-wheel caster (see fig. 38 and table 1). The asphalt mastic and the coal-tar mastic

showed poor resistance to abrasion (see table

2).

10. Alumina Cement-Rubber Latex

Composition

The alumina cement-rubber latex composition floor with an aggregate of marble chips

gave good performance, especially as a monolithic type of floor over a strip-wood subfloor

(see figs. 39 and 40). Although the steel-tired

truck wheel and the steel-wheel caster made

moderate depressions in the fioor, there was no

evidence of fracturing. The floor was worn to a moderate degree by the walking wheel (see table 2 .)

11. Magensium Oxychloride Composition

The magnesium oxychloride composition

floor with an aggregate of granite chips and

granite dust showed very good performance

(see fig. 41). It was worn to only slight extents by the steel-tired truck wheel and the walking

wheel (see table 1 and 2).

12. Portland-Cement Concrete

The 1:2:4 portland-cement concrete floor performed fairly well (see fig. 42). It was

pitted and worn somewhat by the steel-tired

truck wheel and the walking wheel (see tables

1 and 2).

[20]
VI. RECOMMENDATIONS AND

CONCLUSIONS

Some of the more generalized recommendations and conclusions that may be drawn from

the several series of performances tests are: Where trucking is to be done, equipping the

truck with rubber-tired wheels in preference

to steel-tired wheels would be of marked benefit

to the durability of almost all types of floor coverings.

The use of felt, or preferably plywood,

underlays with thin floor coverings over stripwood subfloors is desirable from the standpoint

of both durability and appearance of the surface.

The removal of felt-backed floor coverings

cemented directly to strip-wood subfloors is extremely difficult and involves high costs in

labor. Where a dry-felt underlay has been

used, removal is much easier. Lignin paste is satisfactory for bonding lining felts to wood

subfloors. It is partially soluble in water

and can be readily removed after dampening

moderately. Asphalt-saturated lining felt is more durable than dry lining felt under severe

traffic conditions, such as trucking. However,

its removal is much more difficult. In general, the results of the several per- formance tests indicate that, of the various

types of floor coverings tested, maple, pecan,

oak, /2-in. rock-elm plywood, %-m. rubber, /{-in.

linoleum, and the magnesium oxychloride

monolithic floor with an aggregate of granite

chips and granite dust are durable floor coverings even under severe service. They showed

very good resistance to abrasion, indentation,

and fracturing. The above flooi' coverings are

among those having a high iiiil iai cost. Among

those having a lower initial cost, the felt-backed

floor coverings having wearing surfaces of lino- leum composition, cellulose nitrate cojii position, and resin-treated cotton-linters siiect showed very good resistance to abrasion. Tlie

thickness of their available wearing siiiface is sufficient to withstand normal wear for a i-ea- sonable length of time. For certain types of occupancy, such as would be encountered in most homes, they should render satisfactory

and economical service. It should not be; con- cluded that the other floor coverings tested do

not have merit. Some possess special properties to a high degree, which may be essential to meet certain conditions. An example would

be cork tile if a high comfort value is important.

Asphalt tiles require an even and rigid subfloor such as is obtained in even-troweled concrete. Asphalt tiles on strip-wood subfloors are

likely to crack and fracture even under foot

traffic. A plywood subfloor would be preferable

to a strip-wood subfloor. Asphalt tiles are among the few types which can be successfully

installed on basement floors which have not

been thoroughly waterproofed.

Most floors of the monolithic type are likely to crack and fracture under moderately heavy

traffic when laid over a strip-wood subfloor. Alumina cement-rubber latex compositions

appear to be exceptions.

The generous cooperation of various manufacturers in furnishing materials for test is gratefully acknowledged.

Washington, December 9, 1941.

o

[21]
i

1

i
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

delay. You will be notified when the amount of your deposit has become exhausted.

If 100 copies or more of any report 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 10^ BMS15 Structural Properties of "Wheeling Long-Span Steel Floor" Construction Sponsored by

the Wheeling Corrugating Co 10(i BMS16 Structural Properties of a "Tilecrete" Floor Construction Sponsored by Tilecrete Floors, Inc 10^ BMS17 Sound Insulation of Wall and Floor Constructions 10^ Supplement to BMS17, Sound Insulation of Wall and Floor Constructions 5(i BMS18 Structural Properties of "Pre-Fab" Constructions for Walls, Partitions, and Floors Sponsored by the Harnischfeger Corporation 10^ BMS19 Preparation and Revision of Building Codes 15jS BMS20 Structural Properties of "Twaehtman" Constructions for Walls and Floors Sponsored by

Connecticut Pre-Cast Buildings Corporation 10^ 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 Walls, 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^

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

[Continued from cover page III] BMS31 Structural Properties of "Insulite" Wall and "Insulite" 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(4 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 The Weston Paper and Manufacturing Co.. 10^ BMS37 Structural Properties of "Palisade Homes" Constructions for WaUs, Partitions, and

Floors, Sponsored by Palisade Homes lOfi BMS38 Structural Properties of Two "Dunstone" Wall Constructions Sponsored by the W. E. Dunn Manufacturing Co 10j5 BMS39 Structural Properties of a Wall Construction of "Pfeifer Units" Sponsored by. the Wisconsin Units Co 10^ BMS40 Structural Properties of a Wall Construction of "Knap Concrete Wall Units" Sponsored

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

Insulating Boards Sponsored by The Celotex Corporation lOfS 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^ BMS47 Structural Properties of Prefabricated Wood-Frame Constructions for Walls, Partitions,

and Floors Sponsored by American Houses, Inc 10^ BMS48 Structural Properties of "Precision-Built" Frame Wall and Partition Constructions

Sponsored by the Hcmasote Co 10^ BMS49 Metallic Roofing for Low-Cost House Construction 10^ BMS50 Stability of Fiber Building Boards as Determined by Accelerated Aging 10^ BMS51 Structural Properties of "Tilecrete Type A" Floor Construction Sponsored by the Tile- crete Corporation

BMS52 Effect of Ceiling Insulation on Summer Comfort 10^ BMS53 Structural Properties of a Masonry Wall Construction of "Munlock Dry Wall Brick"

Sponsored by the Munlock Engineering Co 10^ BMS54 Effect of Soot on the Ratmg of an Oil-Fired Heating Boiler 10^ BMS55 Effects of Wetting and Drying on the Permeability of Masonry Walls 10^ BMS56 A Survey of Humidities in Residences lOfi BMS57 Roofing in the United States—Results of a Questionnaire lOjS BMS58 Strength of Soft-Soldered Joints in Copper Tubing . 10^ BMS59 Properties of Adhesives for Floor Coverings 10j5 BMS60 Strength, Absorption, and Resistance to Laboratory Freezing and Thawing of Building

Bricks Produced in the United States 15f5 BMS61 Structural Properties of Two Nonreinforced Monolithic Concrete Wall Constructions.- _ 10^ BMS62 Structural Properties of a Precast Joist Concrete Floor Construction Sponsored by the Portland Cement Association 10^ BMS63 Moisture Condensation in Building WaUs 10^ BMS64 Solar Heating of Various Surfaces 10(4 BMS65 Methods of Estimating Loads in Plumbing Systems 10^ BMS66 Plumbing Manual 20^ BMS67 Structural Properties of "Mu-Steel" Prefabricated Sheet-Steel Constructions for Walls,

Partitions, Floors, and Roofs Sponsored by Hprman A. Mugler 15(5 BMS68 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 3 15<5 BMS69 Stability of Fiber Sheathing Boards as Determined by Accelerated Aging 10^ BMS70 Asphalt-Prepared Roll Roofings and Shingles 15c BMS71 Fire Tests of Wood- and Metal-Framed Partitions 20^ BMS72 Structural Properties of "Precision-Built, Jr." Prefabricated Wood-Frame Wall Construction Sponsored by the Homasote Co 10j5 BMS73 Indentation Characteristics of Floor Coverings . 10^ BMS74 Structural and Heat-Transfer Properties of "U. S. S. Panelbilt" Prefabricated Sheet-Steel Constructions for Walls, Partitions, and Roofs Sponsored by the Tennessee Coal, Iron & Railroad Co 15(4 BMS75 Survey of Roofing Materials in the North Central States 15^5 BMS76 Effect of Outdoor Exposure on the Water Permeability of Masonry WaUs 15(5 BMS77 Properties and Performance of Fiber Tile Boards 10(4 BMS78 Structural, Heat-Transfer, and Water-Permeability Properties of Five Earth-Wall Con-

' structions . 20f5 BMS79 Water-Distributing Systems for Buildings . 15^ BMS80 Performance Tests of Floor Coverings for Use in Low-Cost Housing: Part 4 15(4







J