A111D7 Eim4^




Ii


Kallonil Bureau of Standards

tVlAR 24 1941
National Bureau of Standards

JUL 16 1943

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

National Bureau of Standards, was imdertaken 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 committee of principal technicians.

CENTRAL HOUSING COMMITTEE

ON RESEARCH, DESIGN, AND CONSTRUCTION

A. C. Shire, Chairman. Howard P. Vermilya, Vice Chairman.

United States Housing Authority. Federal Housing Administration.

Sterling R. March, Secretary.

Pierre Blouke, John S. Donovan,

Federal Home Loan Bank Board. Farm Security Administration.

Hugh L. Dryden, George W. Trayer,

National Bureau of Standards. Forest Service (F. P. Laboratory).

Louis A. Simon, Joseph M. DallaValle,

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 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 Forest Service is cooperating with both

committees on investigations of wood constructions.

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

NATIONAL BUREAU OF STANDARDS Lyman J. Briggs, Director

BUILDING MATERIALS

and STRUCTURES

REPORT BMS68

Performance Test of Floor Coverings for Use in :

>' Low-Cost Housing: Part 3

PERCY A. SIGLER

and ELMER A. KOERNER

ISSUED JANUARY 31, 1941

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 • I94I

FOR SALE BY THE SUPERINTENDENT OF DOCUMENTS, WASHINGTON, D. C. • PRICE I5 CENTS
Foreword

Various installations of floor coverings have been subjected to performance tests at the National Bureau of Standards as part of a

research program on buUding materials suitable for low-cost house

construction. Technical information of their relative ability to withstand service should be of aid to consumers and to installers in select- ing floor coverings and methods of installation to meet various

flooring problems.

This report presents the results of a test on a third series of

40 installations in the Bureau's floor-testing chamber, as a supplement

to reports BMS34 and BMS43.

Lyman J. Briggs, Director.

[n]
Performance Test of Floor Coverings for Use

In Low-Cost Housing: Part 3

By PERCY A. SIGLER and ELMER A. KOERNER

CONTENTS

, Page

Foreword ii I. Introduction 1 II. Floor-testing chamber and equipment 2

III. Test conditions and procedure 2 IV. Description of test installations 4

Page V. Results 4 VI. Summary 6

VII. Comments and conclusions 22

VIII. Selected references 23

ABSTRACT

A performance test was conducted in the

j floor-testing chamber of the National Biu-eau

of Standards on a third series of 40 test instalj| lations. Included in the test were linoleums

'I in sheet and tile form, cork-composition tile,

Ij sheet rubber, rubber tile, asphalt tiles, fiber- board tiles, felt-base floor coverings having

1

1 various wearing surfaces, three monolithic

floors, and a number of wood floors. The

bonding agents used included lignin pastes,

cumar-resin cement, alumina cement-latex

paste, rubber cements, various asphaltic adhesives, and nails. Installations were made on

I concrete, strip-wood, and plywood subfloors.

Installations on strip-wood subfloors were made

ij with underlays of dry and asphalt-saturated

ij lining felts. Descriptions of the testing equip-

( j ment and test installations are given. Results

i! showing the relative depth of the depressions

in the floor coverings during the test are

J presented in tables. Brief summaries of the

|! manner in which the various test installations

i performed are given, and photographs of the

I test panels after 48,000 cycles of the testing

I' equipment are shown.

I. INTRODUCTION

There are Federal specifications for a number of nontextile floor coverings which can be

used as a basis for securing good-quality merchandise of a particular type [1].^ Comparable information on the different types is of

direct and economic interest to the consumer

in selecting a floor covering to meet his particular need. In order to provide technical

information of this nature, studies of some of

the important properties of floor coverings have

been made at the National Bureau of Standards

in connection with a general research program

on building materials and structures. One phase of these studies consisted of laboratory performance tests of various installations of floor coverings. Lack of information on such important factors as quality of merchandise, condition of subfloor, extent of maintenance, and magnitude of exposure make

direct comparisons in service difficult. In these

performance tests it was possible to control

many of the factors aft'ecting performance in

service. However, it was not found possible

to include all such factors. No attempt was made to ascertain the effects of finishing coats,

maintenance, age, and atmospheric conditions.

This report presents the results of a performance test on a third series of 40 installations in

the Bureau's floor-testing chamber. The re- sults obtained on the two previous series of

installations were published in reports B1MS34

1 Figures in brackets refer to the list of selected references at the end of

this paper.
and BMS43 [2, 3]. Included in report BMS34

are the results of tests on several kinds of

linoleum, felt-base floor coverings with various

wearing surfaces, pressed fiberboard, and stripwood floors of maple, white oak, and yellow

pine. Report BMS43 contains the results of

tests on battleship linoleum, rubber in sheet and

tile form, felt-base floor coverings with different

wearing surfaces, magnesium-oxychloride mololithic floors, a cement-latex monolithic floor,

and asphalt tiles of various compositions. The

only alteration in the equipment used in the

three performance tests was the substitution of a rubber-tired truck wheel in the second and

third tests for one of the two steel-rimmed

truck wheels used in the first test. In order to obtain results within a comparatively short time, a laboratory test must

necessarily be accelerated and severe. The

testing equipment was a modification of that

previously used in a study of industrial-type

floors [4]. The materials tested represented

good-quality merchandise in their respective

fields. The generous cooperation of various

manufacturers in furnishing materials for test

is gratefully acknowledged.

Other laboratory investigations have been

conducted on various floor coverings and

adhesives to determine their relative merits

with respect to specific properties. The results

obtained in some of these investigations have

been published [5, 6].

II. FLOOR-TESTING CHAMBER AND

EQUIPMENT

The floor-testing chamber contains a concrete circular track 4 ft wide, S% in. thick, and

approximately 40 ft in diameter, with a metalshod concrete curb on each side. The circular

track is divided into 20 test spaces by metal

thresholds, the surfaces of which are 4 in. above

the structural slab. Wood or concrete subfloors and the various floor coverings were in- stalled in these test spaces. Two different in- stallations, 3 ft long, were made in each test space. Figures 1 and 2 show portions of the circular

track and the testing equipment used in this

performance test. The principal features of

the equipment were a "walking wheel", G

(fig. 1), a platform truck. A, and two casters,

Sand F (fig. 2).

The equipment was propelled around the

track at about 2 miles an hour by the walking

wheel, which was 4 ft in diameter and carried a load of approximately 275 lb. The wheel was

shod with eight wooden blocks, H (fig. 1), 6 by

13 by V/z in., which were covered with a cus- hioning layer of rubber ji in. thick and a wearing

surface of leather % in. thick. This arrangement produced a bumping and slipping action

between the wheel and the floor coverings and

imitated, to some extent, a walking action.

Dxu:'ing the second half of the test, No. 3 grit

garnet cloth was placed over the eight leathersurfaced shoes in order to accelerate the abrasive action. The average slippage of the walking wheel during the test was approximately 1 percent.

The platform truck was equipped with two

wheels of 12-in. diameter. The inner wheel, B

(fig. 1), had a solid rubber tire, 2K in. wide, and

carried a load of approximately 500 lb. The

outer wheel had a slightly crowned steel rim, 3

in. wide, and carried a load of approximately

600 lb. On the front of the truck were mounted two

lever mechanisms, C (fig. 2). A swivel steel- wheel caster, E. of 2-in. diameter and %-in.

width, was attached to one of the levers and

exerted a force of 20 lb normal to the floor. A

steel-ball caster, F, of 1-in. diameter, was

attached to the other lever and exerted a force

of 10 lb normal to the floor. Helical springs,

D, were used for applying the loads on the

casters. The number of cycles around the track made

by the testing equipment was recorded by a

counter, R (fig. 1), mounted at the side of the

track and operated by an arm attached to the

truck. A dial depth gage, S (fig. 2), was used

to measure the depressions made in the floor coverings by the equipment. The depth gage

had a span of 8 in. and was equipped with a

flat-ended foot of ^s-in. diameter. The foot

exerted a pressure of 20 Ib/in^.

III. TEST CONDITIONS AND

PROCEDURE

With a few exceptions, the concrete subfloors

used in this performance test were the same

subfloors used in the two previous tests. The

concrete consisted of 1 part of cement, 3 parts

of sand, and 4 parts of gravel, by weight. The

surface of the concrete had a steel-troweled

finish and was thoroughly cleaned before in- stalling the new floor coverings. New wood

subfloors were installed and consisted of either

tongued-and-grooved strip flooring or plywood.

The strip flooring was blind-nailed with 8d cut

nails to four wooden sleepers spaced 12 in. on

centers. The sleepers were approximately

parallel to the direction of travel of the truck

and were embedded in concrete. The plywood was face-nailed to the sleepers, at intervals of

6 in., with 6d barbed and rosin-coated box

nails. The floor coverings were installed during

July and August of 1939. Atmospheric conditions in the testing chamber during the installations ranged from 55 to 75 percent in relative

humidity and from 70° to 90° F in temperature.

A setting-up period of at least 2 weeks was

allowed before starting the test. The per- foi-mance test was started on September 11,

1939, and was stopped on March 19, 1940,

after 48,000 cycles of the testing equipment.

Atmospheric conditions in the testing chamber

during the test ranged from 50 to 75 percent in

relative humidity and from 30° to 85° F in

temperature. The floor coverings were swept

at least once every 500 cycles of the equipment,

so that any effect on the results of loose particles from other test floors was negligible.

The floor coverings were subjected to 50

cycles of the testing equipment, after which

reference marks of white enamel were placed at

intervals beside the paths made by the walking

wheel and the two truck wheels. Initial depth

measurements were recorded for use in determining the depth of compression and wear

caused by the equipment. On each of the 40

installations, 5 measurements were taken along

each of the three paths, making a total of 600

readings. These measurements were repeated

at 4,000, 10,000, 20,000, 24,000, 30,000, 40,000,

and 48,000 cycles of the equipment. During

the first 24,000 cycles the eight shoes of the

walking wheel were surfaced with strips of

leather belting, 6 in. wide. During the second

24,000 cycles the leather-covered shoes were

surfaced with strips of No. 3 grit garnet cloth,

6 in. wide, which were replaced with new strips

every 2,000 cycles. At the end of the test the

floors were washed with soap and water and

then photographed. In taking the photographs, a spot light, with the rays at an angle

of approximately 45 degrees with the surface

of the track, was used as a source of light in

order to more clearly show any fractures or

blisters in the floor coverings.

IV. DESCRIPTION OF TEST

INSTALLATIONS

The 40 test installations in this performance

test involved 26 different floor coverings and 1

different adhesives. With a few exceptions,

specimens of each floor covering were installed on both a concrete and a wood subfloor. An

outline of the test installations is given in

table 1.

V. RESULTS

The depths of the depressions in the floor coverings made by the two truck wheels and

the walking wheel, at different stages of the

performance test, are recorded in table 1. In general, the rubber-tired truck wheel

caused very little damage to the floor coverings

and bonding agents. The steel-tired truck

wheel, however, caused failures ranging from

small fractures or blisters in some of the floor coverings to complete crushing or separation

from the subfloor of others. Many of the floor coverings were indented to an appreciable

degree by the action of the steel-tired truck

wheel. For the same floor covering the depressions were much greater on a wood subfloor

than on a concrete subfloor. This was due to the compression and permanent deformation

of the wood subfloors and to the compression

of the felt underlays where used.

The depressions in the floor coverings caused

by 24,000 cycles of the walking wheel surfaced

with leather appeared to result principaUy

from compression rather than wear. With a few exceptions the depths of the depressions were small. 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. The averages were computed from the differences in the depths of

[4]
Table 1.—Test installations and results of measurements for depth of compression and wear

Subfloor

Concrete-.-

Strip wood ' Conrrete

Strip wood < Concrete

Strip wood ' Concrete.-.

Strip wood

'

Concrete. .- do

-do.

-do.

-do- Plywood ' Concrete.

Plywood ' ConcreteStrip wood

Concrete

Strip wood'

Concrete- --

----do^--- Plywood'- ----doi—

-

Concrete'-

Strip wood<"- ConcreteL _

.

Strip wood'

ConcretC-.-

Plywood"-

Concrete'-

Wood sleeppers.

Concrete'.

.

Strip wood"

Concrete

Underlay

NoneLining felt None

Lining felt

'

None

Lining felt ' None

Lining felt None

-do-

.do-

-do.

-do.

-do., .do.

-do-

-doLining felt i. None

-do.

.do-

-do-

.do.

.do-

.doLining felt' None

Lining felt" None

-do-

-do-

-do-

-do.

Asphalt - laminated

sheathing paper. None

Bonding agent

Resin cement, cu- mar resin. Lignin paste ----do

-do- -do.

-do

-do

do Cut-back rubber

cement. Rubber dispersion, soap type. Alumina cementlatex paste. ----do

Lignin paste. do

do

-do- -do-

.-.-do-.... Cut-back

cement. rubber

Lignin paste Alumina cement^late.x paste. Asphalt emulsion, soap type. -Alumina cement-latex paste. Asphalt emulsion, soap type. do

-do.

.do-

-do- Cut-back asphalt.

-do.

-doBlind-nailed, 8d cut

nails. Warm asphalt

Blind-nailed, 4d cas- ing nails. Hot asphalt

Floor covering

Type and description ^

Marbleized linoleum; marbleized pattern, white.

... do Marbleized linoleum; marbleized pattern, tan. do. Linoleum tile;' marbleized

pattern, mahogany; burlap

backing. do ' Cork-composition tile:e plain

pattern, gray; no fabric backing. do e Sheet rubber; marbleized pat- tern brown. Rubber tile;e marbleized pattern, gray.

.Taspe linoleum; jaspe pattern, brown.

Felt base; printed pattern, lavender; wearing surface, enamel.

Felt base; printed pattern, red; wearing surface, enamel.

...do

Felt base; mottled pattern, white; wearing surface, rpsin- treated cotton-linters sheet duplexed to felt backing.

.do. Felt-base t!le;s jaspe pattern, brown; wearing surface, cel- lulose nitrate composition. do e Felt-base tile;" jaspe pattern,

green; wearing surface, cellu- lose nitrate composition. do s

.4sphalt tile; e plain pattern,

green; 1-minute indentation.

0.010 in.k do e ^

.do E k_

-do B k.

Asphalt tile; s plain pattern,

green; 1-minute indentation,

0.012 in. t

do e Asphalt tile; eplain pattem,red; 1-minute indentation, 0.010

in.tdo e if Asphalt-impregnated fiberboard

tile; m plain pattern, green and

red. -...do »

For footnotes, see end of table.

Asphalt-impregnated fiberboard

tile; "= plain pattern, dull black. Strip Douglas fir;" B and better

grade, ed.ee-grained, flat-back; density, 27 lb/ft 'p White-oak unit-block; <> i flat- grained, two metal splines on

back. Red-oak unit-block; ' i flat- grained, two metal splines on

back. Rock-elm plywood tile; ' 3-ply

,

tongued-and-grooved.

Nominal

thick- ness

Hi

Hi

%i

Me

Vi

Average depth of depression made by

Rubbertired truck wheel

10, 000

cycles

0.000

.002

.000

.000

.000

.000 .000

.000

.000

.000

.000

.000

.000

.001 .000

.000

.001

.004

.001

.001

.000

.000

.000

.002

.000

.001 .001

.000

.003

.008

.003

.000

(»)

(')

(')

48, 000

cycles

0. 000

.00,5 .000

.000 .000

.000

.000

.000

.000

.000

.000

.000

.001 .001

.000

.000

.004

.001

.001

.000

.000

.000

.002

.000

.001

.001

.001 .003

.010

.003

.000

.001

.001

.001

steel-tired truck wheel

10, 000

cycles

jn. 0.000

.008 .000

.00,5 .000

.005

.001

.006

.000

.000

.003

.006

.011 .003

.010

.005

.015 .007

.009

.002

.005

.010

.012

.004

.006

.004

.007

.018

.016

.015

.011

{»)

(•)

(')

48, 000

cycles

0.000

.034 .002

.017

.003

.014

(>)

.018 .000

.001

.009

.021

.023

.043

.007

.040 .012

.041 .016

.030

.025

.018

(^)

.128

.044

. 125 .024

.061 .115

.066

.064

•.025

>.028

'.031

[5]
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

cycles

10. 000

cycles

48, 000

cycles

24, 000

cycles

48. 000

cycles

18R Strip wood"-

doc dc

Concrete

do"

\i-in. sisal-fiber mat.

rubberized. None

Asphalt - impreg- nated sheating

paper.

None . ..

None Rock-elm plywood tile:' ' 3-ply,

tiles joined together with

metal dowel pins. Douglas-fir plywood; » 5-ply Magnesium-oxychloride composition reinforced with ex- panded metal; plain pattern,

green; aggregate, granite dust; density, 118 lb/ft,' p crushing

strength, 9,400 lb/in.2 Alumina cement-latex composition; plain pattern, dark

gray; aggregate, ground cork and silica; density, 61 Ib.W

1:2 cement-mortar topping; ag- gregate, Potomac-river sand; cement-water ratio, 2\,i; in- terval between placing and

trowel!ng,3'/2 hr.; damp-cured

for 6 days; density, 137 lb/

ft;3 p crushing strength, 8,800

lb/in.2

in.

Vi

Vi

in.

(')

.000

.001

.009

.000

in.

». 003

.000

.003

.013

.OOC

in.

(')

.015

.003

.019

.002

in.

'. 017

.046

.039

.037

.011

in.

(•)

.001

.002

.014

.001

in.

'. Oil

.009

.014

.040

.011

19L 19R

Face-nailed, 6d box

nails. Floor covering as in- stalled.

do

«0L._ do..._ do._

» i=left half of panel; i?=right half of panel (facing the panels from the inside of the circular track).

i> Color listed is the predominating color.

" Edge-grained Douglas fir, 25^2 in. thick, with a 238 in. face.

A 1 lb/yd' dry lining felt bonded to subfloor with lignin paste.

• 1^ lb/yd2 asphalt-saturated lining felt bonded to subfloor with lignin paste.

' Size of tile, 834 by 8?i in.

E Size of tile, 9 by 9 in. h Floor covering was too severely damaged to measure accurately.

• Douglas fir plywood, 94 in. thick, 5-ply.

i ?4 Ib/yd^ dry lining felt bonded to subfloor with lignin paste.

k Method prescribed in Federal Specification SS-T-306, Tile; Asphalt.

' Subfloor given a priming coat of cut-back asphalt primer. = Size of tile, 12 by 24 in.

n Douglas fir plywood, 'A in. thick, 5-ply.

» Surface given one heavy coat of a sealer. p At 65-perc-ent relative humidity and 72° F temperature.

1 Size of unit-block 10 by 10 in.

f Surface had a factory-applied finish.

• Accuracy of depth-gage measurements was questionable due to slight warping or displacement of floor covering. Measurements reported were made with either a micrometer or a straight edge and feeler gage after removal of the floor covering.

« Size of tile, 8J4 by 17 in.

" Surface had a broom finish.

compression and wear at 24,000 and 48,000

cycles given in table 1. With a few exceptions the ball and roller casters caused very little damage to the floor coverings.

The accompanying photographs, figures 3 to 42, show the general condition of the floor coverings at the end of the test. The five paths shown in the photographs are, from left to right, those made by the rubber-tired truck

wheel, the steel-ball caster, the walking wheel,

the steel-wheel caster, and the steel-tired truck

wheel. The small white dots in the photographs are the white-enamel reference marks.

VI. SUMMARY

Brief summaries of the manner in which the

various test installations performed are herewith presented.

The /8-in. marbleized linoleums, panels IL,

2L, IR, and showed very good performance,

with the possible exception of panel 2L (see figs.

3, 4, 5, and 6). In panel 2L a dry lining felt was used over the strip-wood subfloor. The

action of the steel-tired truck wheel caused the

dry lining felt to laminate, resulting in an

appreciable fracture of the linoleum (see figure

4). In panel 2R, where an asphalt-saturated

[6]
Table 2.

Average wear offloor coverings caused by 24,000

cycles of the "walking wheel" surfaced with abrasive

cloth »

Floor covering

Marbleized linoleum; H in.; white _ _ Marbleized linoleum; \i in,; tan Linoleum tile; '4 in.; mahogany

Cork-composition title; \i in.; gray. Sheet rubber; J-i in.; brown

Rubber tile; ],i in.; gray

Jaspe linoleum; %2 in.; brown..

Felt base; Hi in.; lavender; wearing surface, enamel _ Felt base ;Yc,iin.; red; wearing surface, enamel _ Felt base; Yei in.; white; wearing surface, resin-treated cot- ton-linters sheet

Felt-base tile; 5^4 in.; brown; wearing surface, cellulose ni- trate composition

Felt-base tile; lit in.; green; wearing surface, cellulose ni- trate composition Asphalt tile; l^i in.; green Asphalt tile; ?i6 in.; green Asphalt tile; ^ie in.; red Asphalt-impregnated flberboard tile; H in.; green and red. .

.

Asphalt-impregnated fiberboard tile; }i in.; dull black

Strip Douglas fir; 2632 in.j edge-grained White-oak unit-block; yi in.; flat-grained Red-oak unit-block; H in.; flat-grained Rock-elm plywood tile; ^2 in.; 3-ply Rock-elm plywood tile; % in.; 3-ply Douglas-firplywood; }2in.;5-p!y

Magnesium-oxychloride composition; M in. ; green Alumina cement-latex composition; H in .; gray

1:2 cement-mortar topping; 1 in

Average

depth of wear

0.008

.001 .002

.001

.004

.006

.005 .008 .010

.002

.001

.002

.018

.014 .009

.042

.033 .033

.005

.007 .005

.011 .008

.012

.026 .010

o 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.

lining felt was used, there was no evidence of

separation in the felt and the steel-tired truck

wheel caused only slight fracture of the linoleum

(see figure 6). The tan marbleized linoleum

showed better resistance to abrasion than the

white marbleized linoleum (see table 2)

.

The /8-in. linoleum tile, panels 3R and 4R,

gave very good performance, particularly with

reference to abrasion (see figs. 7 and 8). On a

concrete subfioor the tiles were fractured slightly

by the steel-tired truck wheel.

The /8-in. cork-composition tile, panels 3L and

4L, showed good performance except under the

action of the steel-tired truck wheel, which

fractured the tiles considerably (see figs. 9 and

10). On a concrete subfioor, panel 3L, tiles along the path of the steel-tired truck wheel

showed failure in bond and were fractured at an

early stage of the test. They were replaced

with new tiles at 1,240 cycles, which proved to be equally unsatisfactory. The tiles showed

good resistance to abrasion.

The )8-in. sheet rubber and the )^-in. rubber

tile used in this performance test were additional

portions of samples used in a previous perform274617°—41 2

ance test [3]. These floor coverings on a concrete subfioor, panels 5L and 5R, gave very

good performance. Along the path of the

steel-tired truck wheel there were small welts

in the floor coverings, caused by accumulations

of the adhesives (see figs. 11 and 12). The

sheet rubber showed slightly better resistance

to abrasion than the rubber tile (see table 2 in

this report and table 2 in report BMS43).

The jaspe linoleum, panel 6L, was an additional portion of a sample used in a previous

performance test [2]. In the previous test, ex- tensive failures in adhesion to the subfloors oc- curred at an early stage of the test and the linoleum was in unserviceable condition at the end

of the test. In the present test, with a different

adhesive, there was no evidence of failure in

bond and the floor covering showed good per- formance (see fig. 13).

The felt-base floor coverings with a wearing

surface of enamel, panels 6R, 7R, and 8L, gave

fair performance considering the type of service

for which they are designed. The floor coverings were in unserviceable condition at the end

of the test (see figs. 14, 15, and 16). On a Douglas fir plywood subfioor, panel 8L, the

steel-tired truck wheel caused considerable

depression and fracture in the floor covering

(see table 1 and fig. 16); otherwise the floor covering presented a more even surface than is usually obtained on a strip-wood subfioor. The

enamel surfaces of the floor coverings were worn

tlxrough in spots by the walking wheel in approximately 30,000 cycles, or 6,000 cycles after

the wheel had been covered with abrasive cloth.

The total depth of wear is shown in table 2. The felt-base floor covering with a wearing

surface consisting of a resin-treated cottonlinters sheet, panels 7L and 8R, withstood the

test very well. Along the path of the steel- tired truck wheel there w^as some failure in

adhesion to the concrete subfloor and slight

fracture of the floor covering (see fig. 17). On

a Douglas fir plywood subfloor, panel 8R, the

steel-tired truck wheel caused appreciable depression and slight fracture in the floor covering (see table 1 and flg. 18). The wearing

surface showed good resistance to abrasion.

The %4-in- and the %4-in. felt-base tiles with

a wearing surface consisting of a cellulose nitrate

composition, panels 9L, lOL, 9R, and lOR,

7]
; r i

Figure 5.

marbleized linoleum on concrete subfloor

(test panel IR)

[8]
[9]

mi

.1

Figure 18.

Y^i-in. felt base, resin treated cotton linters sheet wearing surface, on plywood subfloor (test panel 8R)

.

Figure 19.

%i-in. felt-base

tile, cellulose nitrate composition wearing surface, on concrete subfloor {test panel 9L)

.

Figure 20.

Y^i-in. felt-base

tile, cellulose nitrate composition wearing surface, on

strip-wood subfloor {test panel

lOL).

13
[14]


[17]
Figure ZS.—Yi-in. asphalt-im- pregnaied fiberboard tile on

concrete subfloor {test panel 15R).

Figure 34.

'^Yi2-in. strip

Douglas fir on wood sleepers

(test panel 16L).

Figure 35.—J^-tn. white-oak

unit-block on concrete subfloor (test panel 17L).

[18]
[19]
Figure 39.

yi-in. jymiglas-fir

plywood on strip-wood subfloor (test panel 19L)

Figure 40.

Yi-in. magnesiumoxychloride composition on

strip-wood s u hfloor {test

panel 19R).

Figure 41.

Yi-in. alumina ce- ment-latex composition on concrete suhfloor {test panel 20R).

[20]
Figure 42.

1-in. cementmortar topping, 1:2 mix, on

concrete subjloor (test panel

20L).

withstood the test very well, with the possible The ]{-n\. asphalt-impregnated fiberboard

exception of panel lOL (see figs. 19, 20, 21, and tiles, panels loL, 16R, and 15R, were in un22) . On a strip-wood subfloor with a dry lining serviceable condition at the end of the perfelt, panel lOL, the steel-tired truck wheel formance test. They were pitted and worn

caused separation in the lining felt and dis- to a considerable degree by both the steel-tired

placed some of the tiles (see fig. 20). On a truck wheel and the steel-wheel caster (see

strip-wood subfloor with no lining felt, panel table 1 and figs. 31, 32, and 33). The painted

lOR, the %4-in. tiles were moderately fractured surface of the tiles was worn through by the

by the steel-tired truck wheel (see fig. 22). walking wheel in approximately 30,000 cycles,

Ridges caused by the strip-wood subfloor or 6,000 cycles after the application of the

showed on the surface of the %4-in. tiles with no abrasive cloth. The total depth of wear is underlay whereas they did not show on the shown in table 2. surface of the %4-iii. tiles with a felt underlay The strip Douglas fir, panel 16L, was in

(compare figs. 20 and 22). The wearing surface unsatisfactory condition at the end of the test, of the tiles showed good resistance to abrasion. The flooring was indented and splintered to The Js-in. and the %6-in. asphalt tiles showed an appreciable degree by both the steel-tired

fair performance on a concrete subfloor (see truck wheel and the steel-wheel caster (see

figs. 23, 24, 27, and 29). They were pitted and table 1 and fig. 34). The Douglas-fir strip worn to a moderate degree by the steel-tired flooring showed poor resistance to abrasion,

truck wheel (see table 1). The )^-in. asphalt The white-oak and the red-oak unit-blocks,

tiles on Douglas fir plywood subfloors with no panels 17L and 18L, showed good performance,

underlay, panels 12L and 12R, showed fair The unit-blocks were moderately compressed,

performance except under the action of the and were fractured or splintered to a slight

steel-tired truck wheel, which crushed the extent, by the steel-tired truck wheel (see table

tiles completely (see figs. 25 and 26). The 1 and figs. 35 and 36). There was no evidence

^ie-in. asphalt tiles on a strip-wood subfloor of failure in bond to the subfloors, although the

with an underlay of felt, panels I4L and UiR, individual strips in the unit-blocks showed a

did not stand up weU in this test. The tiles slight tendency to warp. The white-oak unit- were crushed by the steel-tired truck wheel blocks showed slightly better resistance to and were fractured to an appreciable degree by abrasion than the red-oak unit-blocks (see

the walking wheel (see figs. 28 and 30). In table 2).

general, the asphalt tiles were worn to a mod- The }2-in. and the %-in. Rock-ekn plywood

erate degree by the abrasive action of the tiles, panels 17R and 18R, were in good con- walking wheel (see table 2). dition at the end of the test. The tiles were

[21]
moderately compressed by the steel-tired truck

wheel (see table 1). There was no appreciable

fracturing or splintering of the tiles (see figs.

37 and 38). The K-in. tile showed better resist- ance to abrasion than the %-in tile (see table 2).

The K-in. tiles showed a slight tendency to warp, and they were not in complete contact

with the concrete subfloor over the entire area

of the test panel. The %-in. tiles laid over a

}^-in. rubberized sisal-fiber mat were held

together very well by the metal dowel pins but were noisy when walked upon.

The K-in. Douglas-fir plywood, panel 19L,

remained in fair condition throughout most of

the test, although at the end it was in unsatisfactory condition. The plywood was indented

and splintered to an appreciable degree by both

the steel-tired truck wheel and the steel-wheel

caster (see table 1 and fig. 39). The splintered

condition did not occur until near the end of the

test. The Douglas-fir plywood showed fair resistance to abrasion (see table 2). The K-in. magnesium-oxychloride composition floor reinforced with expanded metal, panel

19R, did not show satisfactory performance on

a strip-wood subfloor. The floor was pitted

and worn appreciably by the steel-tired truck

wheel (see table 1 and fig. 40). A fine crack

developed in the floor along the entire path of

the walking wheel (see fig. 40). The floor showed only fair resistance to abrasion (see

table 2). The K-in. alumina cement-latex composition

floor, panel 20R, showed unsatisfactory per- formance. The surface was depressed appreciably by the steel-tired truck wheel and was also depressed to a moderate degree by the rubbertired truck wheel and the leather-shod walking

wheel (see table 1 and fig. 41). There was no

evidence of fracture in the floor and bond to the concrete subfloor was excellent. The floor

was worn to an appreciable degree by the abrasive action of the walking wheel (see table 2).

The 1-in. cement-mortar topping, panel 20L,

showed good performance. The topping was

pitted and worn to a slight degree by the steel- tired truck wheel (see table 1 and flg. 42).

The fine cracks showing along the path of the

walking wheel are due to internal shrinkage of

the topping. The topping showed fair resist- ance to abrasion (see table 2).

VII. COAIMENTS AND CONCLUSIONS

Physical properties of floor coverings which

should be considered and which have a bearing on their performance and durability in service are resistance to abrasion, resistance to tear and

fracture, indentation characteristics, dimensional changes with change in atmospheric conditions, and resistance to cleansing and finishing

materials. Floor coverings should be allowed

to come to a moisture and temperature equilibrium normal to the location before being in- stalled in order to minimize the effect of dimensional changes after installation.

In order to obtain a satisfactory installation

of a floor covering, a number of factors must be

considered in addition to the physical properties

essential to all floor coverings. A dry, even,

rigid, and clean subfloor is necessary for most

floor coverings. A subfloor should be thoroughly inspected for these requirements and

appropriate alterations made where needed.

New concrete subfloors should be allowed to dry

thoroughly before instaUing a floor covering.

Over a strip-wood subfloor an xmderlay of lining

felt is beneficial to thin floor coverings. Dry

lining felt can be readily removed from the subfloor whereas the removal of asphalt-saturated

felt is difficult. Where traffic conditions are

[22]
severe, especially trucking, dry lining felt is likely to separate in itself. Asphalt-saturated

lining felt is considered preferable under such

conditions. Douglas-fir plywood used as a subfloor furnishes an even surface, which is especially desirable for thin floor coverings or those

which fracture readily. Wliere traffic or loads

are likely to be heavy, a subfloor of lower compressibility would be necessary.

Many types of floor coverings need to be

bonded to a subfloor. A failure in the bond is very likely to result in pronounced failure in the

floor covering. Failure of a bond may result

from an unclean or wet condition of the subfloor, separation in an underlay, a faulty adhesive or method of installation, or from excessive

dimensional changes of a floor covering with

changes in relative humidity and temperature.

In interpreting the results of this and the two

previous performance tests [2, 3], it should be

realized that the tests were greatly accelerated

and represent very severe service. In the selec- tion of a floor covering and method of installation, the nature of the exposure to which the

floor will be subjected, the desires of the occu- pant as to appearance and comfort, and the

service per unit of total cost (initial and mainte- nance or renewal) are of importance. In this

respect, some of the lower-cost floor coverings

and methods of installation, even though less durable, may render economical and satisfactory

service for some types of occupancy.

VIII. SELECTED EEFERENCES ^

[1] Federal specifications for floor coverings:

Title Symbol Price Linoleum; battleship _ LLL-L-.351

Linoleum; plain, inlaid, and

printed LLL-L 361 bi^ Carpet; cork _ LLI^C-96 5ft Tile; cork__ LLI^T-431 H

Tile; asphalt _ . SS-T-306 5^

Tile; floor, rubber... ZZ-T-301 H

Floor-covering; rubber, shcet_ ZZ-F-461 Sfi Matting; rubber _ ZZ-M-71 H

[2] P. A. Sigler and E. A. Koerner, Performance Test

of Floor Coverings for Use in Low-Cost Housing:

Part 1, NBS Building Materials and Structures Report BMS34 (1940). lOfi. [3] P. A. Sigler and E. A. Koerner, Performance Test

of Floor Coverings for Use in Low-Cost Housing:

Part 2, NBS Building Materials and Structures Report B MS43 (1 940) . 1 0(4

.

[4] W. E. Emley and C. E. Hofer, Test of floor coverings

for -post-office workrooms, J. Research NBS 19, 567 (1937) RP1046. lOfi.

[5] P. A. Sigler and Myrtle B. Woodward, Indentation

and Recovery of Low-Cost Floor Coverings, NBS

Building Materials and Structures Report BMS14

(1939). lOi.

[6] P. A. Sigler and R. L Martens, Properties of Adhesives for Floor Coverings, NBS Building

Materials and Structures Report BMS59 (1940).

10?;. Washington, October 5, 1940.

' Articles may be purchased from the Superintendent of Documents,

U. S. Government Printing Offlcc, Washington, D. C, at the prices indicated.

[23]
1
BUILDING MATERIALS AND STRUCTURES REPORTS

On request, the Superintendent of Documents, U. S. Governnaent 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 vdll 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 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 10^5 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 Company's "Frameless-

^_ Steel" Constructions for Walls, Partitions, Floors, and Roofs 10(5 (iBMSlO Structural Properties of One of the "Keystone Beam Steel Floor" Constructions Sponsored by the H. H. Robertson Co 100 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(i 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

Wheeling Corrugating Co 10^ BMS16 Structural Properties of a "Tilecrete" Floor Construction Sponsored by Tilecrete Floors, Inc 100 BMS17 Sound Insulation of Wall and Floor Constructions 100 BMS18 Structural Properties of "Pre-Fab" Constructions for Walls, Partitions, and Floors Sponsored by the Harnischfeger Corporation 100 BMS19 Preparation and Revision of Building Codes 150 BMS20 Structural Properties of "Twachtman" Constructions for Walls and Floors Sponsored by

Connecticut Pre-Cast Buildings Corporation 100 BMS21 Structural Properties of a Concrete-Block Cavity-Wall Construction Sponsored by the National Concrete Masonry Association 100 BMS22 Structural Properties of "Dun-Ti-Stone" Wall Construction Sponsored by the W. E. Dunn Manufacturing Co 100 BMS23 Structural Properties of a Brick Cavity-Wall Construction Sponsored by the Brick

Manufacturers Association of New York, Inc 100 BMS24 Structural Properties of a Reinforced-Brick Wall Construction and a Brick-Tile CavityWall Construction Sponsored by the Structural Clay Products Institute 100 BMS25 Structural Properties of Conventional Wood-Frame Constructions for Walls, Partitions,

Floors, and Roofs 150 BMS26 Structural Properties of "Nelson Pre-Cast Concrete Foundation" Wall Construction

Sponsored by the Nelson Cement Stone Co., Inc 100 BMS27 Structural Properties of "Bender Steel Home" Wall Construction Sponsored by The

Bender Body Co 100 BMS28 Backflow Prevention in Over-Rim Water Supplies 100 BMS29 Survey of Roofing Materials in the Northeastern States 100 BMS30 Structural Properties of a Wood-Frame Wall Construction Sponsored by the Douglas

Fir Plywood Association 100 BMS31 Structural Properties of "Insulite" Wall and "Insulite" Partition Constructions Sponsored by The Insulite Co 150 BMS32 Structural Properties of Two Brick-Concrete-Block Wall Constructions and a Concrete- Block Wall Construction Sponsored by the National Concrete Masonry Association. . 100

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

[Continued from cover page III] BMS33 Plastic Calking Materials 10^5 BMS34 Performance Test of Floor Coverings for Use in Low-Cost Housing: Parti 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.- lOji BMS37 Structural Properties of "Palisade Homes" Constructions for Walls, Partitions, and

Floors, Sponsored by Palisade Homes 10(4 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^ BMS40 Structural Properties of a Wall Construction of "Knap Concrete Wall Units" Sponsored

by Knap America, Inc lOfS 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 bj' The Celotex Corporation 10^^ BMS43 Performance Test of Floor Coverings for Use m 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 Homasote Co lOfi 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 b}'^ the Tile- crete Corporation 10^ BMS52 Effect of Ceiling Insulation on Sunamer Comfort . 10^5 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 Rating of an Oil-Fired Heating Boiler 10^ BMS55 Effects of Wetting and Drying on the Permeability of Ma,sonr3' Walls 10^ BMS56 A Survey of Humidities in Residences 10^ BMS57 Roofing in the United States: Results of a Questionnaire lOp

BMS58 Strength of Soft-Soldered Joints in Copper Tubing 10^ BMS59 Properties of Adhesives for Floor Coverings 10^ BMS60 Strength, Absorption, and Resistance to Laboratory Freezing and Thawing of Building

Bricks Produced in the United States 15(5 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 100 BMS63 Moisture Condensation in Building Walls 10^ BMS64 Solar Heating of Various Surfaces 10?^ BMS65 Methods of Estimating Loads in Plumbing Systems 100 BMS66 Plumbing Manual 20(4 BMS68 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 3 150