AlllDD TTEflST

NATL INST OF STANDARDS & TECH R.I.C.

A1 11 00992859

/Acoustical and thermal performance of e TA435 .U58 W7;1975 C.I NBS-PUB-C 1975

v> J

NBS BUILDING SCIENCE SERIES 77

acoustical and Thermal Performance

of Exterior Residential

Walls, Doors and Windows

U.S. DEPARTMENT OF COMMERCE / National Bureau of Standards
The Building Science Series

The Building Scieiico. Series disseminates technical information developed at the National Bureau of Standards on

i)uilding materials, components, systems, and whole structures. The Series presents research results, test methods, and performance criteria related to the structural and environmental functions and the durability and safety characteristics of building elements and systems. These publications, similar in style and content to the NBS Building Materials and Structures Reports (1938-59),

arc directed toward the manufacturing, design, construction, and research segments of the building industry, standards organizations, and officials responsible for building codes. The material for this Series originates principally in the Center for Building Technology of the NBS Institute

for Applied Technology. The publications are divided into three general groups: Building Systems and Processes;

Health, Safety and Comfort; and Structures and Materials. For further information regarding these publications

please contact the Scientific and Professional Liaison Section, Center for Building Technology, Institute for Applied Technology, National Bureau of Standards, Washington, D.C. 20234.

[See mailing list announcement on last page!
OF STANDARDS

NOV 2 <! 1975

Acoustical and Thermal Performance of

Exterior Residential Walls, Doors and Windows

Hale J. Sabine and Myron B. Lacher

Owens-Corning Fiberglass Corporation

Granville, Ohio 43023

Daniel R. Flynn and Thomas L. Quindry

Institute for Basic Standards

National Bureau of Standards

Washington, D.C. 20234

U.S. DEPARTMENT OF COMMERCE, Rogers C. B. Morton, Secretary

James A. Baker, III, Under Secretary

Dr. Betsy Ancker-Johnson, Assistant Secretary for Science and Technology

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Acting Director

Issued November 1975
Library of Congress Catalog Card Number: 75—600084

Nat. Bur. Stand. (U.S.), Bldg. Sci. Ser. 77. 170 pages (Nov. 1975)

CODEN: BSSNBV

/U.S. GOVERNMENT PRINTING OFFICE

WASHINGTON: 1975

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 (Order by SD Catalog No. C13.29/2:77). Price $2.35 (Add 25 percent additional for other than U.S. mailing).
Abstract

Laboratory tests of sound transmission loss, thermal transmittance , and rate of

air leakage were conducted on full scale (9 feet high x ik feet wide; 2.7 x 1+.3 meters)

specimens of typical residential exterior wall constructions, either unbroken or penetrated

by a door or window. The walls were of wood frame construction with gypsum board dfywall

interior finish and exterior finishes of wood siding, stucco, or brick veneer. Additional

acoustical tests were run on a number of individual doors and windows. A total of 109

acoustical tests and kQ thermal tests are reported. The resultant data are compared with

literature data on similar constructions. Correlations developed among the several

quantities measured will assist more rational design where both energy conservation and

noise isolation must be considered.

Key Words; Acoustics , air infiltration, air leakage, architectural acoustics, building

acoustics, doors, energy conservation, heat loss from buildings, heat transfer, sound

transmission loss, thermal resistance, thermal transmittance, windows.

iii
Table of Contents

Page

1. Introduction and Scope • 1

2. Description of Test Specimens 3

2.1. Walls 3 2.2. Doors 5 2.3. Windows T

2. k. Combinations ih

2.5. Cracks and Openings 15

3. Sound Transmission Loss Tests l6

3.1. Background l6

3.2. Experimental Procedure 23

3.3. Calibration Procediires and Uncertainties 2k

3. h. Results 25

3.^.1. Summary and Conclusions 25

3.U.2. Discussion 28

a. Walls. 28

b. Doors 28

c . Sealed Windows 33

d. Unsealed Windows ko

e. Combinations of Windows in Walls kf

3.5- Comparison of Results with Those of Other Investigations k^

3.5.1. Walls 1+T 3.5.2. Doors

3.5.3. Windows 5^ 3.5.^. Cracks and Openings 6I

h. Thermal Transmittance and Resistance Tests • 71

k.l. Background 71

k.2. Experimental Procediire 73

U.3. Calculation Procedures and Uncertainties 75

h.k. Results 75

U.U.I. Summary and Conclusions 75

k.h.2. Discussion 76

a. Walls 76

b. Doors 78

c . Windows 78

4.5. Comparison of Results with Those of Other Investigations • • • 83

U.5.1. Walls 83

1+. 5.2. Doors 8U

U.5.3. Windows • 8U

iv
5. Air Leakage Tests

qY

5.1. Background gj

,5.2. Experimental Procedure gg

5.3. Calculation Procedures and Uncertainties ^0

5.I+. Results

5.I+.I. Summary and Conclusions

5.U.2. Discussion «... 92

a. Doors ^2

b. Windows p2

5.5- Comparison of Results with Those of Other Investigations

6. Correlations among Sound Transmission Loss, Thermal Transmittance

,

and Air Leakage Test Results

6.1. Sound Transmission Loss and Air Leakage

6.2. Thermal Transmittance and Air Leakage 201

6.3- Sound Transmission Loss and Thermal Transmittance 2Q2^

7. References - ]_Qg

Appendix A. Metric (Sl) Conversion Factors .: ; . . . II3

Appendix B. Atixiliary and Filler Walls in Sound Transmission

Loss Tests , xik

Appendix C. Detailed Soimd Transmission Loss Test Results 121

Appendix D. 'Detailed Thermal Test Results 150

Appendix E. Detailed Air Infiltration Test Resiilts I56

List of Figures

Page

Figure 1. Application of wood siding to frame wall installed in sound

transmission facility : k

Figure 2. Application of building felt and wire mesh prior to stucco

application h

Figure 3. Brick veneer wall with opening cut for picture window 6

Figure h. Detail of brick veneer wall construction with resilient

channel and cavity insulation 6

Figure 5- Solid core flush wood door mounted in wood siding wall for

thermal test 8

Figure 6. Wood french door movmted in ,wood siding wall for sound

transmission and air infiltration test 6

Figure 7- Wood double hung window installed in filler wall 9

Figure 8, Aluminiim single hung window ' 11

V
Figure 9- 6 x 5 ft picture window instaU-ed in wood siding wall- . 11

Figure 10. Auxiliary construction erected on interior side of wood

siding wall for sound transmission testing of window 12

Figure 11. Plastic coated wood operable casement window 12

Figure 12. Aluminum sliding window 13

Figure 13- Plastic coated wood sliding glass door 13

Figtire 1^. Limp-wall mass law transmission loss l8

Figure 15- Chart for determining the overall sound transmission loss,

TL^, of a wall with a penetration ' . . . 20

Figure l6. An example of a Sound Transmission Class contour fitted

to a sound transmission loss curve 22

Figure IT- Sound transmission loss vs frequency data for wood-siding,

wood-stud exterior wall with cavity insulation ... 26

Figure l8. So\ind transmission loss vs frequency data for wood-siding,

wood-stud exterior walls of four different constructions "... 29

Figure 19. Sound transmission loss vs frequency data for stucco, wood

stud exterior walls of three different constructions 29

Figure 20. Sound transmission loss vs frequency data for "brick veneer,

wood stud exterior walls of three different constructions 30

Figure 21. Envelope of sound transmission loss vs frequency data for

five doors sealed into the frame 30

Figvire 22. Sound transmission loss vs frequency data for the three

wood doors sealed into the frame 31

Figure 23. Sound transmission loss vs frequency data for the two

urethane foam core doors sealed into the frame 31

FigTore 2k. Sound transmission loss vs frequency data for three wooden

doors unsealed with weather stripping, compared with data

for the same doors when sealed 32

Figure 25. Comparison of effect of three types of weather stripping

on sound transmission loss vs frequency data for doors 32

Figure 26. Comparison showing the effect of adding a storm door on the sound transmission loss vs frequency of a solid core wood door 3^

Figure 27. Comparison of sound transmission loss vs frequency data for

different types of sealed glazing 35

Figure 28. Envelope of soimd transmission loss vs frequency data for

five sealed windows with single-strength glazing 36

Figure 29. Sound transmission loss vs frequency data for three types

of insulating glass : 36

t

vi
Figure 30. Comparison of sound transmission loss vs frequency data

for insulating glass with data for single glazing of the

same surface density 37

Figure 31. Comparison of sovind transmission loss vs frequency data for

sealed single-strength windows with storm sash with data for

sealed windows, glazed single-strength with storm sash . 38

Figure 32. Detail of framing in filler wall to receive pict\are window sashes. ... hi

Figiore 33- Sound transmission loss vs frequency data for 6 x 5 f

t

pict\ire window, double-strength glazing, with perimeter

cracks of controlled size kl

Figure 3^. Sound transmission loss vs frequency data for 6 x 5 f

t

picture window, glazed with 1 in. insulating glass, with

perimeter cracks of controlled size k2

Figure 35- Comparison of effect of perimeter cracks of the same area, hut different widths, on the sound transmission loss vs frequency for a 6 x 5 ft picture window, glazed with 1 in.

insulating glass k2

Figure 36. Theoretical sound transmission loss of surface with cracks,

assuming the sound transmission loss of the sealed surface

is at least 10 dB higher than that of the surface with cracks kk

Figure 37. Comparison of the envelope of sound transmission

loss vs frequency data for all sealed windows with

the envelope of data for all unsealed windows , locked

and unlocked kk

Figiire 38. Comparison of sound transmission loss vs frequency data

for sealed and unsealed windows, glazed single strength 1+5

Figure 39- Comparison of sound transmission loss vs frequency data

for sealed and unsealed windows, glazed 7/l6 in. insulating

glass kS

Figure hO. Comparison of measured sound transmission loss vs frequency

data for a 6 x 5 ft picture window, glazed single strength,

in a wood siding wall with that predicted from the transmission losses and areas of the wall and window 1+8

Figure 1+1. Comparison of measiired so\ind transmission loss vs frequency

data for a 6 x 5 ft pictvire window, glazed 1 in. insulating

glass, in a wood siding wall with that predicted from

the transmission losses and areas of the wall and window 1+8

Fig^lre 1+2. Comparison of measured sound transmission loss vs frequency

data for a 6 x 5 ft pictin-e window, glazed single strength,

in a "brick veneer wall with that predicted from the transmission losses and areas of the wall and window 1+9

Figure 1+3. Comparison of measured sound transmission loss vs frequency • data for a 6 x 5 ft picture window, glazed 1 in. insiilating

glass, in a brick veneer wall with that predicted from

the transmission losses and areas of the wall and window 1+9

vii
Figure hk. So\ind transmission loss vs frequency data for vood-siding,

wood-stud, exterior walls 50

Figure U5. Sound transmission loss vs frequency data for plasterboard

interior walls 51

Figure U6. Sound transmission loss vs' frequency data for solid core wood doors 52

Figure ^7- Sound transmission loss vs frequency data for solid core wood doors (cont.) • 53

Figure h8. Sound transmission loss vs frequency data for hollow

core wood cores 55

Figure U9. Sound transmission loss vs frequency data for sealed

windows, of various types and sizes, with douhle-strength

(3 mm) glazing 56

Figure 50. Sound tr-ansmission loss vs frequency data for sealed

windows, of various types and sizes, with single-strength

glazing 57

Figure 51- Mean sound transmission loss (arithmetic average of the

values over the range 100 to 3150 Hz) of sealed windows

vs glass thickness 58

Figure 52. Sound Transmission Class of sealed windows vs glass thickness 58

Figure 53. Sound transmission loss vs frequency data for-l/U in.

laminated glass with an internal damping layer 59

Figure 5^- Sound transmission loss vs frequency data for 7/l6 in.

insulating glass units 60

Figure 55- Sound transmission loss vs frequency data for double

glazing with a nominal U in. separation between the two panes. ..... 62

Figure 56. Sound transmission loss vs frequency data for double glazing

with an average nominal spacing of about 2 to 3 in. between

the two panes 63

Figure 57- Theoretical sound transmission loss vs frequency data

for slits in the middle of a wall between two reverberant

rooms 6h

Figure 58. Theoretical sound transmission loss vs frequency data for

slits in the middle of a wall between two reverberant rooms 65

Figure 59- Comparison of experimental results and theoretical predictions

for the soiind transmission loss of l/k in. cracks around

pictiare windows 67

Figure 60. Comparison of experimental results and theoretical predictions

for the sound_ transmission loss of 1/8 in. cracks around

picture windows 68

Figure 61. Comparison of experimental results and theoretical predictions

for the soimd transmission loss of I/I6 in. cracks around

pictiire windows 69

viii
Figure 62. Comparison of experimental resvilts and theoretical predictions

for the sound transmission loss of 1/32 in. cracks around

picture windows JO

Figure 63. Schematic section of calibrated hot box facility used for

thermal tests 7U

Figure 6h. Thermal resistance vs mean temperature data for a wood siding,

wood stud wall 79

Figure 65. Infrared thermograph of warm side of insulated wall 80

Figure 66. Infrared thermograph of warm side of insulated wall

penetrated hy a double-hung wood window 80

Figure 67. Experimental setup for measuring air filtration of doors and

windows in the sound transmission facility 89

Figure 68. Air infiltration through gauged cracks around picture window 93

Figure 69. Air infiltration, as a function of crack width, through

gauged cracks around picture window at 0.3 in. water

pressiare 93

Figure 70. Air infiltration, per foot of crack, for locked wood and woodplastic double-hung windows compared with ASHRAE design values 96

Figure 71- Experimentally determined values for STC^ - 10 log (S^/S^)

plotted vs experimentally determined values for -10 log

(V/V^) 99

Figure 72. Experimental values for the decrease in sound transmission

loss due to leaks aroimd windows or doors versus predicted

values 99

Figure 73. Expected decrease in Sound Transmission Class as a function

of air leakage rate divided by area 100

Figure 7^- Experimentally observed increase in effective thermal

transmittance of 9 x lU ft walls , with and without penetrating doors or windows, vs the increase predicted by equation (23) • • . . 102

Figure 75 • Experimentally observed increase in effective thermal transmittance of 9 X li+ ft walls , with and without penetrating

doors or windows, vs the increase predicted by equation {2h) 102

Figure 76. Comparison of Sound Transmission Class and thermal transmittance for basic walls, doors, and windows 103

Figure B-1. Filler wall after cutting opening for picture window 115

Figure B-2. Sound transmission loss vs frequency data for wood stud

drywall with resilient channel and cavity insulation 115

Figure B-3. Apparent sound transmission loss vs frequency data for

complete filler wall, concrete surround not covered II6

Figure B-k. Auxiliary construction added to concrete surround II6

Figure B-5. Filler wall and auxiliary construction over concrete surround 117

ix
Figure 3-6. Apparent sound transmission loss vs frequency data for complete

filler wall vith auxiliary construction added to concrete

surround 117

Figure B-T- Apparent sound transmission loss vs frequency data for

complete filler wall with a\ixiliary construction added to concrete wall. The three curves represent computations

tased on three different values for the wall area 119

Figure C-1. Regions which were sealed for Test W-23-T1 1^8

Figure C-2. Detail of brick-veneer, wood-stud exterior walls ihQ

Figure. C-3. Detail of stucco,' wood-stud exterior walls 1^9

Figure C-k. Detail of wood-siding, wood-stud exterior walls 1U9

List of Tables

Page

Table 1. Thermal transmlttance and thermal resistance of various

2 X k in. wood stud walls with 1/2 in. gypsum board on the

interior surface 77

Table 2. Thermal transmlttance of doors and wall/door combinations 8I

Table 3. Thermal transmlttance of windows an^ wall/window combinations 82

Table h. Comparison of ASHRAE design values for thermal transmittances

of doors with the results of the present investigation (without

an impose.d air pressure difference) 85

Table 5- Comparison of ASHRAE design values for thermal transmittances

of windows with results of present investigation (for locked

windows without an imposed air pressvire difference) 86

Table 6. Comparison of sound transmission loss data and thermal transmlttance data for walls, doors, and windows 10^^

Table C-1. Sound transmission loss of exterior walls 121

Table C-2. Sound transmission loss of exterior doors ' 122

Table C-3. Sound transmission loss of windows. . 123

Table C-k. Sound transmission loss of walls containing windows 125

Table C-5. Sound transmission loss of windows with cracks and 'openings 126

Table C-6. Sound transmission loss performance data 129

Table D-1. Thermal test data for walls, doors and windows 150

Table E-1. Air infiltration of 3 x 7 ft exterior doors I56

Table E-2. Air infiltration of windows .157

Table E-3. Air infiltration of windows with cracks and openings I58

X
1. Introduction and Scope

There are many considerations which affect the final design of the exterior shell of

a residential 'building. Esthetics and economics are, of course, major concerns hut two

factors which are increasing in importance in the design decision are factors emphasized by

the energy "crisis" and environmental considerations.

These two increasing concerns are for conserving heating and cooling energy through

improved thermal performance and for achieving a sufficiently quiet interior environment in

which to live comfortably by providing Isolation from exterior noise.

Quite often a good acoustical design for an exterior wall is also a good thermal

design since some of the same general principles are followed. The elimination of paths

for excessive air leakage, for instance, can improve both the thermal and acoustical

performance as can the use of wall insulation and storm windows

.

The objective of the tests presented in this report was to obtain design information

consisting of meaningful, representative data on the acoustical, thermal, and air

infiltration performance of typical doors, windows, and exterior walls as used in

residential construction.

Heat transmission and air infiltration data are useful for:

Accurately estimating heat loss or gain for residences.

Providing reference data on conventional constructions with which to compare

performance of new types of construction designed to improve thermal energy

utilization.

Similarly, sound transmission data are useful for:

Estimating noise levels within residences due to outside sources such as aircraft and traffic.

Providing reference data on conventional constructions and components against

which to compare specified or measured performance of new types of

construction.

Designing combinations of walls with doors or windows to provide a given

overall sound isolation.

Laboratory tests of sound transmission, heat transmission, air infiltration, and heat

transmission in the presence of air infiltration were conducted on full-scale (9 x 1^+ ft)

specimens of typical residential wall constructions, either unbroken or penetrated by doors

or windows . The walls were of wood frame construction with gypsum board drywall interior

finish. Three exterior finishes were used: wood siding, stucco, and brick veneer.

The test program on doors and windows was intended only to provide a representative

data base on those types commonly used in residential construction. No attempt was made to obtain a statistical sampling of all available doors and windows nor to establish

definitive averages and ranges of performance. Also, with one or two exceptions as noted,

no tests were made on experimental constructions or variations designed to improve

performance or to illustrate new departures in building practice. In accordance with the

above method of selection, all units tested were purchased from the local' lumber yard or supplied at no cost by a manufacturer from his standard product line.

The door tests included five exterior units, plus the addition of a storm door and a substitution of weather stripping in one of the exterior units.

Three general types of windows were tested, namely, wood, wood with exterior plastic

coating, and aluminum. The window sizes ranged from 3 x U ft up to a 6 x T ft sliding

glass door. Other window variables included type of glazing, number of lights (i.e., panes

of glass in a given sash), and the addition of storm sash.

1
This report is organized as follows. Section 2 contains descriptions of the test

specimens. In Sections 3, ^, and 5, which have parallel structures to facilitate

cross-comparisons, the sound transmission loss, thermal transmittance , and air infiltration

tests, respectively, are discussed. In each of these three sections, an introductory

sub-section provides background information and references to related literature. Chapter 6 presents correlations among the so\md transmission, thermal transmittance, and air leakage

test results.

In order to make the test results more immediately useful to American architects and

designers, customary engineering units are used rather than the (metric) International

System of Units (Sl) normally used in NBS publications. A table of conversion factors is

given in Appendix A.

2
2. Description of Test Specimens

The program covered tests on three types of specimens:

(a) Continuous unbroken exterior walls

(b) Individual doors or windows

(c) Combinations of doors or windows set in exterior walls

The tests on continuous walls were conducted by building the wall construction into the

entire 9 x lU ft test opening of the sound or thermal test facility. These walls were built

in strict conformity with normally good field practice except that, in addition, they were

thoroughly caulked into the test opening around the entire perimeter.

For tests on combinations of doors or windows set into exterior walls, field practice

was again followed. The doors and windows were installed, with their frames, as complete

units into roiagh openings framed to the required nominal dimensions . The outer perimeters

of all door and window frames were thoroughly sealed to the exterior side of the wall

opening in accordance with good field practice.

For sound transmission tests on individual doors or windows, the same installation

procedure was followed except that a "filler wall" construction surrounding the unit under

test was specially built to eliminate errors due to flanking transmission. Details of this

construction are discussed in Section 3 and in Appendix B. In some cases, auxiliary

construction was added to an existing exterior wall construction, and in other cases a complete filler wall was built.

In all cases, the exterior side of the test construction faced the sound source room or the thermal cold chamber (which was also the pressurized side for infiltration tests).

2. 1. Walls

The sound transmission test program included all of the walls, doors, and windows

listed below. To avoid duplication, a complete tabulation of the test specimens is not given in this chapter but rather is included in Appendix C, where all of the sound transmission test results are presented. The thermal transmittance test program covered only a limited selection of the test specimens.

Three types of wood frame exterior walls were tested having outside facings of painted

wood siding, unpainted stucco, and brick veneer, respectively. The interior surfaces werj,

unpainted 1/2 in. gypsum board drywall. The framing throughout was 2 x k in. wood studs,—

l6 in. on centers (o.c).

2/ The basic constructions— are described as follows

:

Wood Siding (Figure l)

Framing - 2 x i+ in. wood studs, l6 in. o.c. Sheathing - 1/2 in. wood fiberboard insulation nailed to studs

Siding - 5/8 by 10 in. redwood nailed through sheathing into studs

Interior - 1/2 in. gypsum board screwed to studs or to metal resilient channels

which were attached to the studs.

^2 X h in. wood stud dimensions were 1 5/8 by 3 5/8 in.

2/ — The purchase of specific brands of building materials used in the fabrication of test

specimens was based on availability. Brand names and company names which appear in

the text or photographs, of this publication do not imply endorsement by the National

Bureau of Standards,

3
4
stucco (Figure 2)

Framing - 2 x k in. wood studs, l6 in. o.c. Sheathing - none

Stucco - No. 15 felt bui:|.ding paper and 1 in. wire mesh nailed to studs. Stucco

applied in 3 coats to T/8 in. total thickness. Dry weight of stucco T.9

Ih/sq ft. Interior - 1/2 in. gypsum hoard screwed to studs or resilient channel

Brick Veneer (Figure 3)

Framing - 2 x U in . wood studs, l6 in. o.c. Sheathing - 3/^ in. wood fiberhoard insulation

Brick - standard face brick 3 1/2 in. wide, spaced 1/2 in, out from sheathing

with metal ties nailed through sheathing into studs. Dry weight of

brick and mortar hi Ib/sq ft.

Interior - 1/2 in. gypsum board screwed to studs or resilient channel

For each wall, variations involving cavity insulation and resilient drywall channels were tested.

The constructions wittiout resilient channel would be more typical of residential

exterior walls, and the tests with channel were included to show the improvement in sound

isolation which might be expected.

3/ The cavity insulation used in all of the walls was Fiberglas— 3 1/2 in. Rll Kraft

Faced Building Insulation. In addition, the wood siding wall with the gypsum board

fastened directly to the studs ^as also tested with Fiberglas 3 1/2 in Friction Fit

Building Insulation, with Alfol—^^Type 2P Hlk (inset stapled) reflective-type insulation

and with 3 in Rll Premium Brand— Paper Enclosed Rock Wool Building Insulation.

The resilient drywall channel, when used, was one of three makes of product which had

been previously tested and found essentially equivalent for sound isolation. The channel

was nailed horizontally to the studs on 2 ft spacing, and the gypsum board was screwed

into the channels (see Figure h) . At the bottom, the gypsum board was screwed into the

studs through a gypsum board base strip in accordance with standard field practice; this,

however, reduces the potential sound isolating value of the resilient channel appreciably,

as shown by earlier tests.

2. 2. Doors

Five types of residential, exterior doors were obtained locally and tested. These

included three wood doors of differing construction, a steel door, and a molded glass

fiber reinforced plastic (FRP), foam filled panel door. The wood doors and the FRP dooy

all fit interchangeably into a single wood door frame unit, and the metal door was furnished with its own wood frame unit. The frame for the three wood doors was furnished

with a spring brass weather strip on three sides and an aluminum threshold with a halfro-und plastic closure strip. The weather strip was later replaced with an extruded

plastic strip for the test on the FRP door and a repeat test on one of the wood doors.

The frame for the steel door was fitted with a magnetic weather strip similar to that

on a refrigerator door. The bottom of the door carried three soft plastic fingers which

closed against a flat aluminum threshold. All doors were nominally 3 x 7 ft and 1 3/h in.

thick with an actual area of 20.0 sq ft.

3/Registered Trademark. Building material brand names are included in this publication

in order to adequately specify the materials used. Use of such names does not imply

endorsement of these materials by the National Bureau of Standards. The "R-values" given

in this paragraph are as stated by the manufacturer and may not agree with the data

obtained under the conditions of the present investigation.

5

One of the wood doors was retested with the addition of an aliominum combination screen

and storm door. The removable storm panes were clamped against soft plastic gaskets, and

the alumin\Mi frame for the door was fitted with thin plastic weather stripping on three

sides. The bottom of the door carried a single plastic strip which wiped against the wood

sill of the main door frame.

The doors are further described as follows:

Flush Solid Core Wood Door (Figure 5)

3 X T ft by 1 3/i+ in.

Weight - 78 lb, 3-9 Ib/sq ft

Fliish Hollow Core Wood Door

3 X 7 ft by 1 3/U in.

Weight - 25 lb, 1.25 Ib/sq ft

Wood French Door (Figure 6)

3 X 7 ft by 1 3/i+ in . 12 lights glazed single strength

Glass area 8.0 sq ft

Weight - 57 lb, 2.85 Ib/sq ft

Flush Steel Door

3 X 7 ft by 1 3/i+ in.

Faces - 0.028 in. steel, separated by plastic perimeter strip

Core - rigid polyurethane , 2 to 2 1/2 lb/cubic ft, foamed in place

Weight - 6U lb, 3.2 Ib/sq ft

FRP Panel Door

3 X 7 ft by 1 3/h in.

Faces and edges - fiberglass-reinforced plastic

Core - rigid polyurethane, 3 lb/cubic ft, foamed in place

Weight - i*7 lb, 2.35 Ib/sq ft

Aluminum Storm Door

3 X 7 ft by 1 inGlazed single strength, glass area 12 sq ft

2. 3. Windows

Three sets of typical residential windows were purchased locally or supplied at no cost

by the manufacturer , as follows

:

All wood

Wood with plastic coating

Alumlniim

Various types of windows were included in each of the above material categories. In the

following descriptions, the dimensions are given as width by height and are approximate.

Double Hung (Figure 7)

3 X 5 ft. Vertically sliding upper and lower sashes, interchangeable in a single frame unit

supplied as part of the complete window assembly.

7
Figure 6. Wood french door mounted in wood siding wall for sound transmission and

air infiltration test. Auxiliary construction on opposite side eliminates

significant flanking sound transmission.
Figure 7. Wood double-hung window installed in filler wall.

9
Single Hung (Figure 8)

3 X U ft. Lower sj.sh vertically sliding, upper sash fixed.

Picture Windov (Figure 9)

6 X 5 ft. Fixed large single sash, normally sealed when installed into frame unit.

For tests, various sashes were sealed directly into rough opening.

Awning (Figure lO)

3 X i+ ft. Upper and lower sashes swing outward from upper hinge on each. Interchangeable sashes were tested in frame unit supplied.

Fixed Casemen€

3 X 5 ft. Sealed integrally into frame unit as received.

Operable Casement (Figure 11

)

U X 5 ft wood and 3 x ^ ft aluminum. Right and left half of window swing outward from

hinges on outer edges, operated by cranks.

Sliding (Figure 12)

3 X U ft. Half of window slides horizontally, other half fixed.

Jalousie

3 X ^ ft. Horizontal glass louvers operable together. Louvers h 1/2 in. wide with 1/2

in . overlap

.

Sliding Glass Door (Figure 13)

6 X T ft. Half of door rolls on track, other half fixed.

Storm Sash

A separate window \init added to the corresponding main window unit for test.

Variations in glazing for the above window types included single strength, double

strength, safety glass, and insulating glass. The safety glass tested consisted of a double layer laminated to a transparent inner septum. Insulating glass consists of two

layers separated by an air space, usually with a mastic perimeter seal. Insulating

glass varies in overall thickness and weight depending on the type and size of window

in which it is used. The types of glazing included in the test program are as follows

:

Single Strength

Nominal thickness 3/32 in.

Nominal weight 1.30 Ib/sq ft

Double Strength

Nominal thickness 1/8 in.

Nominal weight 1.63 Ib/sq ft

3/l6 in. Safety Glass

3/32 in. layers laminated

Nominal weight 2.60 Ib/sq ft

10
Figure 9. 6 x 5 ft pictiore -window installed in wood siding wall.

11
Figure 10. Auxiliary construction erected on interior side of wood siding wall for

so\md transmission testing of window.
Figure 13. Plastic coated wood sliding glass door.

13
3/8 in. Insulating Glass

3/32 in. layers, 3/l6 in. air space

Nominal weight 2.60 Ib/sq ft

T/16 in. Insulating Glass

1/8 in. layers, 3/l6 in. air space

Nominal weight 3-3 Ib/sq ft

1 in. Insiilating Glass

3/16 in. layers, 5/8 in. air space

Nominal weight 5-2 Ib/sq ft

1/^ in. Louvers (in jalousie window)

Nominal weight 3.3 Ib/sq ft

For additional information, a test was run on a single 3 x i+ ft sheet of l/k in.

laminated glass. This is a special product designed for high transmission loss consisting

of two sheets of 1/8 in. glass laminated to a transparent inner damping layer. The measured

areal density was 3.0 Ib/sq ft.

The windows are further characterized as to whether each sash, or the entire unit in

the case of a picture window, contains single or multiple panes.

Single light - one pane in each sash, or each half of a storm window

Divided lights - multiple panes in each sash

2. 4. Combinations

Sound transmission tests were run on four combinations of a wall penetrated by a window

as follows

:

Wood siding wall with 6 x 5 ft picture window, glazed single strength

Same, except pictiire window glazed insulating glass

Brick veneer wall with each of the above windows

The two walls represent the extremes of transmission loss to be expected in wood frame

exterior constructions. Except for the sliding glass patio door, the picture window had the

largest area of any window tested and would be expected to cause the largest change in overall transmission loss on the basis of relative areas of window and wall. The two glazings

in the picture window represented extremes in transmission loss as. a function of glazing.

Thermal transmission tests on walls penetrated by doors or windows were run only on the

wood siding wall with gypsum board fastened directly to the studs and with Fiberglas 3-1/2

in. Friction Fit Building Insulation in the cavities, for each of the following penetrations:

Doors

Flush solid core wood door, brass weather strip

Same, plus aluminum storm door

Flush steel door, magnetic weather strip

Molded plastic panel door, extruded plastic weather strip

14
t

Windows

Wood double-huSg"3 'oc 5 ft glazed single strength, single light

Same, plus wood storm sash, glazed single strength, single light

Wood douhle-hung 3 x 5 ft glazed insulating glass, single light

Wood picture window 6 x 5 ft glazed single strength, divided lights

Same, except insulating glass, single light

2. 5. Cracks and Openings

Soun,d transmission tests of the doors and windows were made under varying conditions of

sound leakage. In every case, a test was made with the door or window completely sealed

with tape or caulking. This established the maximum transmission loss of which the unit

under test is capable. A special series was run on the 6 x 5 ft picture window in which

accurately measured cracks of varying width and length were provided around the perimeter.

All of the other doors and windows were tested as normally closed, in addition to the

completely sealed condition. Further tests were made on some of the windows to compare the

locked with the unlocked condition and to show the effects of slight amounts of opening.

Thermal transmission tests and the accompanying air infiltration tests on the doors and

windows were made only on the normally closed condition. All tests on the double-hung window

were made with the window locked and unlocked.

Air infiltration tests in the two-room sound transmission facility were run for the

same leakage and crack conditions as stated above for the sound transmission tests, except

for complete sealing.

15
3. Sound Transmission Loss Tests

3. 1. Background

There are many useful texts and summary articles for the reader who is not familiar

with acoustics. The books by Harris [l] and Beranek [2] contain chapters by experts in

different areas of acoustics. Young [3], Franken [h] , and Beranek [5] discuss the fundamental concepts and the use of decibels. Rudnick [6] and Kurze and Beranek [?] describe

outdoor sound propagation. Beranek [8] and Embleton [9] summarize the theory of sound

propagation in small and large rooms, respectively. Ingerslev and Harris [lO] and Cook and

Chrzanowski [ll] discuss solid-borne and air-borne noise respectively, while Ver and Holmer

[12] summarize related analytical f^ydings . The chapter by Sabine [13] provides a discussion of acoustical materials.—

Beranek [ih] describes different criteria for human response to noise in buildings.

Three recent publications [15-1?] of the U. S. Environmental Protection Agency provide an overview of human response to noise.

In the following brief discussion, only those concepts needed for understanding and

use of soiand transmission loss data are addressed. For additional definitions of

acoustical terms, see [l8,19].

The spatially-averaged mean-square sound pressure in a room is , within the limitations

of certain simplifying assumptions , proportional to the total sound power entering the room

and inversely proportional to the total sound absorption in the room. In a typical

building this sound power can enter a room from sources within the room, from sources elsewhere in the building, or from sources exterior to the .building . In the present

report, only sound due to exterior sources is of concern.— Furthermore, attention is

confined to sounds transmitted through the exterior facade, as opposed to roofs, chimneys,

crawl spaces, etc.

Sound transmission through a partition can be described in terms of the sound

transmission coefficient , x, of the partition. The sound transmission coefficient in a specified frequency band is the fraction of the airborne sound incident on the partition

that is transmitted by the partition and radiated on the other side.

For an infinitely large panel in free space with a plane wave incident on one side,

2

where p-j^ is the mean-square sound pressure characterizing the incident wave and p^ is the

mean-square sound pressure characterizing the transmitted wave. The mean-square sound

pressure is related to the normally-measured sound level, L, by the expression, L =

2 2 10 log-,„ (p /p ) , where p =20 micropascals is the reference pressure.

— Figures in square brackets refer to the literature references at the end of

this report. —'^Of course sound can leave a building and then re-enter it elsewhere (e.g. , open

windows across a courtyard). This can be treated as noise of exterior origin.

.16
Usually the effectiveness of a partition is described in terms of the sound transmission loss .

TL = 10 log , (2)

where the logarithm is to the hase ten. Combining equations (l) ^and (2), it is seen that,

in free space ,

TL = - L^, (3)

where and are the sound pressure levels of the incident and transmitted waves,

respectively.

The transmission coefficient and the transmission loss are functions of the direction

from which the incident wave impinges upon the partition. At sufficiently low frequencies,

where a simple partition behaves approximately as a limp mass which is vibrated by the

sound field and the partition is thin compared to the wavelength of sound, the limp-wall

mass law [12,20] is approximately valid. As shown in Figure 1^+, for a given angle of

incidence, the sound transmission loss increases as a function of the product of frequency

(of the sound wave) and the areal density (mass per unit area) of the partition. The

transmission loss is a maximum for a normally incident sound wave and decreases as the

sound approaches grazing incidence.

The exterior facade of a building needs to provide adequate attenuation of sound

arriving from a number of directions. Thus, it seems appropriate, for design purposes, to utilize a sound transmission loss corresponding to an average over many angles of

incidence. For some situations, such as the upper floors of a high-rise building near a highway, the sound will typically arrive at near-grazing incidence and the design value for

sound transmission loss should be selected accordingly. However, for residential con- structions such as are considered in the present report, sound could be expected to arrive

from essentially all angles. Thus for this report, "random incidence" sound transmission

loss was measured by placing the partition under test in an opening between two rever- beration chambers — acoustically hard rooms that cause the sound to be reflected many

times so there is essentially equal probability of sound striking the test partition from

any direction. The dashed curve in Figure ih shows the theoretical "field-incident mass

law", which is derived from the digarete-angle mass law by averaging over all angles of

incidence from normal (0°) to 78°.— It is seen that the use of "random-incidence data"

for design purposes would be conservative for sound striking the partition at angles from

0° (normal) to beyond ^+5°- Unless it is known that sound will usually impinge at near-grazing incidence, the use of data obtained under random-incidence conditions should

be suitable for exterior walls

.

Since real walls do not behave as ideal limp masses, the rather simplistic curves shown in Figure ik cannot be taken too seriously. However, they show two featiires which

are important to remember — sound transmission loss generally increases as the mass of the

partition increases and also increases as the frequency of sound increases. The actual

frequency dependence of the sound transmission loss can be complicated by resonance phenomena and "coincidence effects" [12, 20] which depend upon, among other things, the

bending stiffness and internal damping of the partition. For constructions which are more

complex, such as a double partition separated by structural elements, the transmission loss

also depends upon how well the several components are vibration isolated from one another.

— The integration is only taken up to 78° rather than 90° so as to obtain better

agreement with experimental data. The finite size of the partition, the effect

of the test facility, and possible damping effects in the wall for near-grazing

incidence are probably responsible for the observed deviations between experiment and the simple mass-law theory Il2, 20-21].

17
100 200 500 1000 2000 5000 10,000 20,000 50,000 100,000

FREQUENCY x AREAL DENSITY, Hz x Ib/ft^

Figure ik. Limp-wall mass law transmission loss. The solid curves correspond to a plane

wave arriving at a discrete angle of incidence. The dashed curve corresponds

to "field-incidence mass law", a sum over all angles of incidence up to 78°-

18
the thickness of any air spaces, and the amount of acoustically absorptive material in

these air spaces [12, 2l]. For many partitions, it is possihle to calculate approximately

the soiind transmission loss as a function of frequency but, in general, empirical data are

required.

When a partition is composed of several elements (i.e., wall, door, window, cracks)

which provide parallel paths through which the sound can be transmitted, the overall sound

transmission coefficient is obtained from [ll, 12]

^1^1 ^ ^2^2 ^2^3 ^

+ + + ...

where is the transmission coefficient for the element of area S^, etc., and the sum- matioh is over all areas of the partition. As an example of the use of equation (U),

consider a ik ft by 9 ft wall having a transmission loss of ^8 dB and being penetrated by

a 3 ft by U ft window having a transmission loss of 32 dB. Solving equation (2) for x' in

terms of TL yields

-TL /lO o . _^

= 10 = 10 = 1.6 X 10

-^^2/1° -3.2 , -k

and = 10 = 10 = 6.3 X 10 .

Substituting these values into eq. (U),

(1.6 X 10~^) X (126-12) + (6.3 X 10"^) X (12) „ , ^^-5

^o - 126 - 7. U X 10

so that, again using eq. (2), the effective transmission loss of the composite wall is

TL^ = 10 log j = Ul dB.

A chart derived from equation {k) for estimating the overall transmission loss of

any combination of a wall and a single penetration such as a door, or window, knowing the area and transmission loss of each component, is shown in Figure 15- The linear portions

of the curves in Figure 15 correspond to situations where nearly all of the sound energy

comes through the portion of the wall having the lower transmission loss so that TL^as TL^ + 10 log (lOO/k), where k is the percent of the total wall area occupied by the door, window,

crack or other path of low sound transmission loss. Consideration of eq. (2) and Figure

15 reveals that even a small area having a low transmission loss can greatly reduce the

overall transmission loss below that of the basic wall structure. Since cracks may have

a transmission loss that is near zero, "leaky" doors, windows, and louvers can vitiate an otherwise good construction. The effect of cracks is discussed in some detail in Sections

3 . 6 and 6.1.

Neglecting interior sources of noise, the average soimd pressure level in a room

having an exterior wall on which soiind is incident from a large range of directions is

given approximately by

= - TL^ + 10 log S/A, (5)

19
5 10 15 20 25 30 35 40 45

TLi-TL2,dB

Chart for determining the overall sound transmission loss, TL , of a wall with

a penetration (e.g., door or window) having a transmission loss, TL^, less than

the transmission loss, TL , of the basic wall construction. The penetration

occupies "k percent" df the total wall area. The transmission loss of the

combination is shown 'in relation to that of the wall as TL-|^ - TL . Example: A

window with TL- = 30 dB occupies 5 percent of the area of a wall with TL = 50 dB.

Then,

TL^ - TL^ = 20 dB

TL, - TL = 8 dB

1' . o TL = 50 - 8 = 1;2 dB

o

20
where is the exterior sound pressure level— , TL is the effective sound transmission

loss of the wall, S is the area of the wall, and A is the total sound absorption (equivalent area of a perfect ahsorber, in the same units as S) in the room. Equation (5) may

he used in applications of the experimental sound transmission loss data presented in

this report.

As discussed previously, sound transmission loss varies markedly with the sound

frequency. The room absorption. A, is also a function, albeit a much weaker one, of

frequency. Thus the sound attenuation in a particular application will depend on the frequency spectrum of the noise. The need to provide a "single-figure rating that can be used

for comparing partitions for general building design purposes" has led to the development,

by the American Society for Testing and Materials (ASTM) , of the Sound Transmission Class

[22] and, by the International Organization for Standardization, of a quite similar rating

scheme [23]. The Sound Transmission Class "is designed to correlate with subjective

impressions of the sound insulation provided against the sounds of speech, radio, television, music, and similar sources of noise in offices and dwellings." [22]

"Excluded from the scope of this classification system are applications involving

noise spectra that differ markedly from those described above.... A particular exclusion

would be the exterior walls of buildings, for which noise problems are most likely to involve motor vehicles or aircraft. In all such problems it is best to use the detailed

sound transmission loss values, in con-junction with actual spectra of intrusive and ambient

noise." [22]

Since there are, at present, no generally accepted _single-figure ratings for exterior

walls, the Sotind Transmission Class has been included in this report to provide a quick way

of easily comparing different partitions. The above-quoted caution should be observed in

applying these data.

Figure I6 illustrates the concept of the Sound Transmission Class. The solid data

points represent the measiired l/3-octave band sound transmission loss over the frequency

range 125 to i+000 Hz. "The STC contour is shifted vertically relative to the test curve until some of the measured TL values for the test specimen fall below those of the STC

contour and the following conditions are fulfilled: The sum of the deficiencies (that is,

the deviations below the contour) shall not be greater than 32 dB and the maximum

deficiency at a single test point shall not exceed 8 dB. When the contour is adjusted to the highest value (in integral decibels) that meets the above requirements, the sound

transmission class for the specimen is the TL value corresponding to the intersection of

the contour and the 500-Hz ordinate. .." [22 ] . The cross-hatched region in Figure 16

indicates the frequencies at which deficiencies occur. For the example shown, the sum of

the deficiencies is 29 dB and the largest single deficiencies occurring are 5 dB, so the

"-8 dB rule" need not be applied.

NBS has in the past prepared several compilations of soimd transmission loss, chiefly

for interior walls, doors, and floor-ceiling assemblies [2U-26] . The most comprehensive of

these is the large report of Berendt , Winzer, and Burroughs [26] which has recently been

reprinted. In I96O, the British Building Research Station published a large compilation of

field data [27]. This is now being updated and expanded. The Experimental Biiilding

Station of Australia has recently published a compilation of laboratory transmission loss

data [28]. Jain and Mulholland [29] and Gillam [30] have described a databank of sound

insulation measurements which is being developed at the University of Liverpool (Great

Britain). A recent study [3l] for the U. S. Department of Housing and Urban Development

includes data on a number of constructions having fairly high sound transmission losses.

—Specifically, L is the sound pressure level corresponding to the sound energy

incident on the wall. Unless the sound source is very close, L^ is nearly

equal to the sound pressure level measured, say, 5 to 10 ft from the exterior

siirface of the wall. Levels measured very close to the wall need to be adjusted

to correct for the effect of soimd reflected back from the wall.

21
CO

TJ

CO- COO

CO

CO

CO<

70

60

50

40

30

20

10

S T C-38

CONTOUR

125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure 16. An example of a Sound Transmission Class contour fitted to a sound transmission

loss curve. The fitting procedure is described in the text.

22
Although the above-referenced compilations contain a few data on exterior walls,

doors, or windows, the vast majority of the data are for interior partitions. There haye

"been some studies [32-36] of the overall attenuation of exterior noise that is provided by

a typical complete building. NBS has published a translation [37] of a French study on the

sotind transmission loss of exterior walls. Section 3-5 includes some references to previous work on the sound transmission loss of windows.

3. 2. Experimental Procedure

Current standard procedures for measuring the airborne sound transmission loss of a partition between two reverberant spaces are based on the theory developed at NBS many

years ago by Buckingham [38], Early experimental work at NBS [39, ^O] contributed to the

development of the ASTM Standard Recommended Practice for Laboratory Measurement of

Airborne Sound Transmission Loss of Building Partitions [hi] and to the later ASTM standard

for field measurements [U2]. The current international test method, ISO Rl)+0-60 [U3], is

similar to these but the procedures are not so completely described. ASTM E90-70 and ISO

Rli+0-60 describe the laboratory procedure for determining the airborne sound transmission

loss of walls of all kinds, floor-ceiling assemblies, doors, and other space-dividing

elements. The procedure is to mount the test specimen as a partition between two

reverberation rooms arranged and constructed so that the only significant soimd transmission between them is through the test specimen. A random incidence sound field is used

for the test and, as discussed previously, the results are most directly applicable to similar sound fields, but provide a useful general measure of performance for the variety

of sound fields to whi'ch an exterior partition may typically be exposed.

Sound transmission tests were run in essential conformity with ASTM E90-T0. The

facility used for the tests is comprised of a Ul+00 cubic foot source room and a 10,000

cubic foot receiving room, both reverberant. The room volumes are large enough to qualify

the facility under E90-T0 recommendations for tests down to a lower frequency limit of 110

Hz. Both dimensions of the 9 x 1^4 ft test opening exceed the minimum dimensions specified

in E90-T0.

The wall in which the test opening, was located was of poured concrete 13 in. thick,

and common to both rooms, with an area of 13 x 22 ft on the 'source room side. This wall

was mechanically isolated by separate footings and by mastic joints from the side walls and

floor and ceiling of both the source and the receiving rooms. Since many of the test

specimens had areas which were quite small compared to the common wall between the source and the receiving rooms, special provisions, described in Appendix B, were made to minimize

flanking sound transmission.

The source room was rectangular and contained no fixed or moving diffusing elements.

Previous tests had shown that the introduction of these elements produced no significant

change in the measurement of room-average sound pressure levels or of transmission loss

values

.

The receiving room was also rectangular but contained an 8 x l6 ft rotating vane and a

nijmber of fixed diffusing panels. These had been permanently installed for other types of

test, so that their effect on transmission loss measurements was not directly established.

Space-time averages of soimd pressure level were obtained by a continuously moving

microphone in each room. In the source room the microphone traversed an 8 ft long arc along a room diagonal, and in the receiving room the microphone was attached to the moving

vane and traversed a l6 ft diameter circle. The time interval for each complete traverse

and for the corresponding period of measurement at each l/3-octave frequency was about 15

seconds

.

The test signal was a broad band noise generated by a BrUel & Kjaer Type lU02 Random

Noise Generator.— The signal was shaped for maximum utilization of sound power and was

— Instrumentation brand names and model numbers are included in this publication

in order to adequately specify the equipment used. Use of such names does not imply endorsement of this equipment by the National Bureau of Standards.

23
divided into a high and low frequency channel, each of which was fed into a 60-watt power

amplifier. The high frequency channel drove a horn loudspeaker and the low frequency

channel a 15 in. cone speaker in an enclosure. The loudspeakers were placed in a room

corner opposite to the test wall.

The maximum sound pressure level developed in the source room was about 115 dB (re 20

micropascals ) . This level was high enough that no corrections for acoustical or electrical

background noise were needed for the highest values of 'transmission loss measured

throughout the program.

Sound pressure levels in each room were measured with separate BrUel & Kjaer Type Ul32

condenser microphones, fed alternately into a Bruel & Kjaer Tjrpe 2112 Audio-Frequency

Spectrometer. The two microphone channels had equal 'overall sensitivity within 0.1 dB at the input to the spectrometer, as measured by a pistonphone at 250 Hz on each microphone.

The difference was less than 1/2 dB at all frequencies up to 6300 Hz, as measiared wit|h both

microphones exi5osed to l/3-octave noise bands in a reverberant field. The source room

microphone was approximately 1/2 dB more sensitive at 6300 Hz and 1 dB at 8000 Hz.

The l/3-octave band frequency levels measured by the _spectrometer were recorded on a

Brllel & Kjaer Type 2305 Level Recorder. Sound pressure levels were read to the nearest 1 dB from the average of the fluctuating recorder trace at each frequency. Measurements were made over a frequency range of 80 to 6300 Hz, although the range only from 125 to kOOO Hz

is commonly reported in standard transmission tests in the United States.

The calculation of transmission loss from measurements of sound pressure level

differences involved the measurement of 10 log A^, where A^ is the absorption of the

receiving room in sabins. This measiorement was made for each test by means of a calibrated

sound power source. The source used was an ILG fan, which is widely used for this purpose.

To calibrate the power of the source, the room average sound pressure level was measured

with the source operating in a room of known room absorption, which was measured by the

decay method.

3. 3. Calibration Procedures and Uncertainties

The overall sound transmission loss of each specimen was computed from the expression

TL = - + 10 log S/A^, (6)

where is the average sound pressixre level in the source room, is the average sound

pressure level in the receiving room, S is the projected area of sound transmitting surface

of the test specimen, and A is the total absorption of the receiving room, expressed in

units consistent with S. This equation generally is considered to be valid provided the

total flow of acoustic energy between the soirrce and receiving room is not too large

A number of papers [kk-60] in recent years have addressed the question of how well

sound transmission loss measurements made in different laboratory or field situations can be expected to agree with one another or with theoretical predictions. It is known that

the size of the source and receive rooms, the nature of the opening in which the specimen

is placed, and the size and method of mounting of the specimen all can influence the test

resxilts . At the present time there are no generally accepted procedures for quantitative

evaluation of the effect of these factors in a given testing facility. Comparative tests

have shown that measurements of sound transmission loss in the facility used for the tests

in this report are in good agreement with tests on nominally identical specimens in other

good facilities in Worth America.

The precision of reading of space-time average sound pressure levels in the two rooms, including levels for the calibrated power source, ranged from about 2 dB at 80 Hz to 1/2 dB

at 6300 Hz. All measured levels were recorded only to the nearest 1 dB. Calciolated values

of transmission loss were also stated to the nearest 1 dB. The calibration of the power

source was checked periodically and found to be constant within the measurement precision

2h
of the sound pressiire levels. The measurement of 10 log A was therefore of the same order

of precision as the measurement of l^vel difference between the rooms.

The overall accuracy of a transmission loss test can he stated in various ways. The

immediate repeatability of a test without removing the test specimen or knowingly changing

the receiving room absorption typically is within 1 dB from 80 to 6300 Hz.

The repeatability of a test on two different installations of the same nominal

construction in the Owens-Corning Fiberglas Sound Laboratory, using different lots of

materials, is shown in Figure IT. The tests were made four months apart on a standard wood

stud exterior wall with wood siding and insulating sheathing on the outside and gypsum

board drywall on the inside. The maximijon difference between the curves at any frequency

from 80 to 63OO Hz is h dB, and the difference between the averages for the two curves is

1.2 dB.

The accnaracy of a transmission .loss test can be affected by flanking transmission

through the wall surrounding the test specimen. This can be of special importance when the

test specimen has a very high, transmission loss or has a comparatively small area, such as

a door or window, in relation to that of the surrounding wall. Significant errors due to flanking were minimized by the auxiliary constructions detailed in Appendix B.

3. 4. Results

Sound transmission loss data were obtained on all of the specimens described in

Section 2. Data were obtained, in many cases, on both individual elements and on combinations. To determine the effect of sound leakage through cracks, tests of doors and

windows were made with the unit sealed in place to establish maximiam capability and with

the unit as normally mounted. In addition, a number of tests were carried out on windows

with large controlled cracks around them.

Complete data for all specimens tested are listed in Table C-6 of Appendix C in the

form of l/3-octave band soiind transmission loss versus frequency for each test. Each set of data is assigned a Sound Transmission Class (STC) rating in accordance with ASTM EU13-73

[22]. Tables C-1 .through C-5 list the tests which were carried out on (C-l) walls, (C-2)

doors, (C-3) windows, (C-U) walls containing windows, and (C-5) windows with cracks and

openings. These five tables are cross-referenced to the detailed test results given in

Table C-6.

Section 3.^.1., below, gives' a summaiy of the test results and certain of the more

important, conclusions. Section 3.^.2. contains a more detailed discussion of the test

results

3. 4. 1. Summary and Conclusions

The summarized test data given below are those obtained only for the specific tests in

this program and do not necessarily apply to general types or classes of construction or products.

The single number performance ratings for sound transmission loss are given as Sound

Transmission Class (STC) as defined in ASTM EU13-T0. In geperal, a high STC rating

corresponds to a high resistance to sound transmission.

1. Wood stud exterior walls with the drywall sec\ired directly to the studs, with insulation board sheathing (except for stucco) and glass fiber cavity insiilation, had STC

values as follows

:

Wood siding 39

Stucco k6

Brick veneer 56

25
70

60

S5 50 -

X

X X

o ° o 6

40

30 X o

o

20

10 _L _L

125 250 500 1000 2000 4000 BAND CENTER FREP JENCY, Hz

Figure 17. Sound transmission loss vs frequency data for wood-siding, wood-stud exterior

wall with cavity insulation. Repeat tests (W-54-71 and W-3-72) on same nominal construction using different lots of materials.

26
The presence of insulating material in the stud cavities, with the dryvall seciired

directly to the studs, made a negligihle difference of less than about 3 dB.

2. If the drywall was attached to resilient channel, the cavity insulation was much more

effective, giving the following STC values:

Wood siding hf

'Stucco ^ 57

Brick veneer 58

3. The measured transmission loss of a wall containing a door or window agreed very

closely with the calculated value hased on the measured transmission loss and area

of each component. The transmission loss of the combination of two components will

always have a value between the respective transmission loss values of each component. A chart for determining the transmission loss of the combination was given in

Figure 15-

k. Cracks can greatly reduce the effective sound transmission loss of wall/window com- binations (see Sections 3- 5-^' and 6.1. for discussions of means to estimate the

sound transmission loss of cracks).

5. Five exterior doors sealed into the frame had STC values ranging from 21 to 31. These values were governed largely by door weight, rather than materials or con- struction, and corresponded to an areal density range of 1.2 to 3.9 Ib/sq ft.

6. The same five doors as normally closed against a weather stripped frame ranged from

20 to 28 STC.

7. A solid core flush wood door having an STC of 30 sealed was reduced to STC 27 when

normally closed against either a spring brass or a plastic weather strip. A steelfaced door had an STC of 28 whether sealed or normally closed against a magnetic

weather strip. The latter was considerably more effective at high frequencies than

the brass or plastic weather strip.

8. The tests on all of the windows when completely sealed showed an overall range of

26 to 39 STC, subdivided as follows:

Single glass (single strength,

double strength, 3/l6 in. safety) 28 - 32

Insulating glass (3/8 to 1 in.) 26-3^

Windows plus storm sash (windows up to 7/l6 in. insulating

glass , storm sash single and

double strength glass) 29-39

9. There were no significant differences due to single versus divided panes or to the

sash and frame material.

10. The insulating glass up to 7/l6 in, thickness was on the whole no better than

single glass in single or double strength.

11. A test on a special 1/h in., laminated glass having an inner damping layer designed

for high transmission loss showed an STC of 3^. The high frequency performance of

this glass was better than standard glass , but the higher STC value was due to its

greater weight.

12. The effectiveness of double glazing, either with insulating glass or with an added

storm sash, depended mainly on the width of separation between the panes.

27
13. The use of standard storm sash with single glazed windows with as wide a spacing

as possible is probably the most effective and economical means of obtaining high

soiond insulation.

ih. Windows installed with weather stripping as furnished showed values averaging

about h STC lower than those measured with complete sealing.

3. 4. 2. Discussion

a. Walls

The tests conducted on the three exterior wall constructions are listed in Table C-1.

Complete data are shown in Figirres l8 to 20. For each wall, the use of cavity insulation

but not resilient channel was considered as "standard" construction as commonly used for

thermal requirements. This is shovm by the left-hand side of each diagram. For the wood

siding wall, an additional test was made on this standard construction, but omitting the

Fiberglas Kraft Faced cavity insiilation. This showed a slight reduction in transmission

loss of from zero to 6 dB over the frequency range with a reduction in STC from 39 to 37. The other three types of cavity insulation in the same construction showed similar results

with STC values of 37 to 39. The relative ineffectiveness of cavity insulation is commonly

observed in single wood stud construction and is due to the transmission of sound by

"vibration through the rigid coupling of both sides to the studs .

The combination of resilient channel and cavity insulation effects a substantial

improvement in transmission loss over the standard wall for most of the frequency range.

For the wood siding wall the increase in STC was 8, from 39 to U7, and for the stucco wall,

11, from h6 to 57. The improvement in the brick veneer wall, however, was only 2, from 56 to 58 STC. This might be explained by the fact that the brick was already partially

isolated from the wood stud portion by the air space and the metal ties.

The tests with resilient channel but without insulation show a lesser improvement over

the standard wall. The test series as a whole indicated that with the inner surface

decoupled by the resilient channel, transmission took place largely through the air cavity

rather than through the studs , thus allowing the sound absorbing action of the cavity

insulation to become fully effective.

b. Doors

The tests conducted on exterior doors are listed in Table C-2. Figure 21 shows the

envelope of frequency curves for the five doors sealed into the frame, with an STC range of

21 to 31. Also shown are theoretical "mass law" lines corresponding to the range of areal

densities of 1.2 to 3.9 Ib/sq ft. The ranges of measured and theoretical data agreed quite

well at the lower frequencies. At the higher frequencies, the lower measured values were

due to stiffness effects which acted oppositely to those of mass.

Frequency ciorves for the three wood doors sealed in place are shown in Figure 22 and

for the doors with foamed plastic cores in Figirre 23. The aforementioned stiffness effects

are shown quite clearly for the foamed plastic doors in the form of sharp dips in the 'curve around 2000 Hz. The wood hollow core door also shows a similar dip at 8OO Hz. These "wave coincidence dips" are further discussed in the following section on windows.

A comparison of sealed versus normally closed doors is shown in Figure 2h for the

three wood doors mounted in the same frame with the spring brass weather strip originally

furnished with the unit. The TL values were significantly lowered only at the higher

frequencies by about 6 dB, with a corresponding change in STC values, of 1 to h.

Figure 25 shows a comparison of three weather strips. Two of these were spring brass

and extruded plastic, the latter being substituted for the former in the same door frame

and with the same solid core wood door. The threshold was a half-round plastic strip. By

referring to the sealed door in Figure 22, it is seen that both weather strips reduced the

TL by about the same amount; namely 3 to 8 dB at the higher frequencies and from 30 to 27

STC.

28
1. 5/8 IN.x 10 REDWOOD SIDING

2. 1/2 IN.INSULATION BOARD SHEATHING

3. 2 IN.x 4 IN.WOOD STUDS 16 IN O.C . 4. FIBERGLAS BUILDING INSULATION

(W-54-71 AND W-55-71 ONLY)

5. NATIONAL GYPSUM RESILIENT CHANNEL

(W-55-71 AND W-56-71 ONLY)

6. 1/2 IN.GYPSUM BOARD^CREWED TO CHANNEL

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz Figxire l8. Sound transmission loss vs frequency data for wood-siding, wood-stud exterior

walls of four different constructions (with or without resilient channels and

with or without cavity insulation)

.

Symbol Test No. Cavity Resilient STC

Insulation Channel

o W-5i+-71 yes

A W-56-71 no W- 55-71 yes

W-U-72 no

z

<

DC

1. 7/8 IN. STUCCO

2. NO. 15 FELT BUILDING PAPER AND

1 IN.WIRE MESH

3. 2 IN.x 4 IN.STUDS 16 IN O.C.

4. FIBERGLAS BUILDING INSULATION

(W-50-71 AND W-52-71 ONLY)

5. NATIONAL GYPSUM RESILIENT CHANNEL

(W-52-71 AND W-53-71 ONLY)

6. 1/2 IN GYPSUM BOARD SCREWED TO CHANNEL

no 39

yes 1+3 yes hi

no 37

1 1 1 1 1 1

60

50 P ./ /

40 y

30

20

10 1 1 1 1 1 1 125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 19- Sound transmission loss vs frequency data for stucco, wood stud exterior walls

of three different constructions (with or without resilient channel and with

or without cavity insulation).

Symbol Test No. Cavity Resilient STC

Insulation Channel

o

A

w-50-71

w-53-71

w-52-71

yes

no yes

no yes

yes

U6

57

29
1. FACE BRICK

2. 1/2-IN. AIR SPACE, WITH METAL TIES

3. 3/4-IIM. INSULATION BOARD SHEATHING

4. 2 IN. X 4 IN. STUDS 16 IN. O.C.

5. FIBERGLAS BUILDING INSULATION

(W-44-71) AND W-45-71 ONLY)

6. NAT.IONAL GYPSUM RESILhENT CHANNEL

(W-45-71 ANDW-46-71 ONLY)

7. 1/2 IN. GYPSUM BOARD SCREWED TO CHANNEL

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 20. Sound transmission loss vs frequency data for "brick veneer, wood stud exterior

walls of three different constructions (with or without resilient channel and

with or without cavity insulation)

.

Symbol Test No. Cavity

Insulation

Resilient

Channel

STC

o W-U1+-T1

V-k6-ll

W-1+5-T1

yes

no yes

no yes

yes

56

58

70

60

50

40

30

20

10

1 1 1 1 1 1

y

y y

y

~ y y —~y /

^

^ / y^ r^y y / y J

1 / 1 1 1 1 1 125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz Figure 21. Envelope of sound transmission loss vs frequency data for five doors sealed into

the frame. The corresponding Soiind Transmission Clsiss range is STC 21-31. The

dashed lines correspond to the field incidence mass law (see Figure 1^+ and

accompanying text) for the range of areal densities (1.2 to 3.9 Ib/sq ft) of the

five doors

.

30
70

60

"5 50 O

o

CO 40

30

20

10

-CI--Q-S

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 22. Sound transmission loss vs frequency data for the three wood doors sealed into

the frame.

Symbol Test No. Specimen STC

O W-93-T1 Wood flush hollow core A W-91-T1 Wood flush solid core W-95-T1 Wood french door

21

30

31

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 23. Sound transmission loss vs frequency data for the two urethane foam core doors

sealed into the frame.

Symbol Test No. Specimen STC

O W-3-T2 Steel faces 28

A W-i+i+-72 Fiberglas reinforced plastic faces 26

31
70

60

50

40

30

20

10 125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 2U. Sound transmission loss vs frequency data (STC 21-31) for three wooden doors

unsealed with weather stripping, compared with data for the same doors when

sealed (STC 20-27).

10 1 1 1 1 1 1 1 125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 25- Comparison of effect of three types of weather stripping on sound transmission

loss vs frequency data for doors.

Symbol Test No. Specimen STC

O W-90-T1 Spring hrass on 3 sides of solid

core wood door; plastic halfroiand threshold strip 27

A W-U2-72 Same except extruded plastic

3 sides 27

W-2-72 Magnetic strip on 3 sides of

steel door, plastic fingers on

"bottom 28

32
For the steel door with magnetic weather strip, thei*e was no significant difference

between the sealed and the normally closed deor. The fact that in hoth cases the TL was

suhst ant i ally higher at most frequencies than that of , the wood solid core door, either

sealed or normally closed, indicated that the magnetic weather strip provides a 5 to 10 dB

tetter sound seal than the other two weather strips in the upper, frequencies. The sharp

dip at 2000 Hz is due to direct transmission through the steel door and therefore could not be controlled by the perimeter seal.

The effect of adding a storm door to the solid core wood door is shown in Figure 26.

For both doors normally closed, the STC was raised from 27 to 3^, and with both sealed

there was a further improvement to h2 STC. This indicates the need for a drastic

improvement in the weather stripping of the storm door in order to approach its fvll

capa-bility when added to the wood door.

c . Sealed Windows

Sealed Single Glazing

The tests conducted on windows with complete perimeter seals are listed in Table C-3.

The data for single glazed windows are summarized in Figures 27 to 31. The overall range

of STC values for sealed windows without storm sash was 28 to 3^. For sealed windows with

storm sash, the range was 29 to 39 STC.

The average characteristics for single glazed windows are shown in the curves of

Figure 27. The STC values are as follows:

Single Strength 28-29

Double Strength 29-32

3/l6 in. safety glass 31

1/h in. laminated with

damping layer 3^

The envelope of all data for five windows with single strength glazing is shown in

Figure 28. This showed a remarkably low spread of 1 to 3 dB over most of the frequency

range in spite of wide variations in window style including single and divided lights, wood

and aluminum frames, and a wide range of sash and pane area. The conclusion is that the

glass rather than the window material and construction was the governing factor in sound

transmission of sealed windows.

Comparison of the curves for the four types of glazing in Figure 27 shows that the

transmission loss in the middle and lower frequencies was controlled essentially by the

surface weight of the glass. For a given frequency, the mass law for single layer

materials states that their difference in transmission loss is equal to 20 times the log of

their areal density ratio. For an overall range of 1.3 to 3.0 Ib/sq ft for the four types

of glass, the predicted spread in TL value was 7 dB, a value which is very closely matched

by the data from l60 to 1000 Hz.

The mass law further states that for a perfectly limp, single layer material of a given weight, the TL increases with frequency at 6 dB per octave. The data curves, however, show, due to stiffness effects, a much lower rate of increase. At the high

frequencies, the observed dips are due to wave coincidence and occur at a critical

frequency which depends on the ratio of surface weight to bending stiffness. For a given

material, the bending stiffness increases with thickness at a more rapid rate than does the

surface weight so that the coincidence dip occiirs at lower frequencies with increasing

thickness. The frequencies of the observed dips for three of the glazings from 2500 to 6300 Hz agreed well with the calculated frequencies based on nominal surface weights and

stiffness for the various thicknesses.

The depth of the coincidence dip is governed by the damping properties of the glass

and its mounting. The dip for the l/k in. laminated glass should have occurred around 2000

Hz, but the large amount of damping provided by the inner layer almost completely filled in

the dip, resulting in a large improvement above 2000 Hz over the 3/l6 in. laminated glass

33
70

60

COD

CO 50

10 J L J L

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 26. Comparison showing the effect of adding a storm door on the sound transmission

loss vs frequency of a solid core wood door.

Symbol Test No. Specimen STC

O W-91-T1 Door alone, sealed into frame

A W-U0-T2 Door unsealed, extruded plastic

weather strip , plus aluminum

storm door, unsealed.

W-i+1-72 As above, both doors sealed

30

k2

34
Figure 27. Comparison of sound transmission loss vs frequency data for different types of

sealed glazing.

SymTjol Test No. Specimen STC

O W-8-T1 single strength

W-33-T1 (average of 5 tests) 28-29

W-l+l-Tl

W-T6-T1

W-26-T2

A W-7-71 double strength

W-32-T1 (average of 6 tests) 29-32

W-3U-TI

W-6U-T1

W-66-TI

W-21-T2

W-18-T2 3/16 in. safety glass 31

V W-22-72 1/h in. laminated glass

with inner damping layer 3^

35
70

10 I

1 ^ 1 1 \ i 1 125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 28. Envelope of sound transmission loss vs frequency data for five sealed windows

with single-strength glazing (Tests W-8-71, W-33-71, V-kl-^l, W-76-T1, and

W-26-72). Windows include: wood and aluminum sash, single and divided lights,

sash areas from 6 to 30 sq ft. The corresponding Soimd Transmission Class

range is STC 28-29.

70

60

^ 50 O

40

30 -

20 -

10 _L _L

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz Figure 29. Sound transmission loss vs frequency data for three types of insulating

glass

.

Symbol Test No. Specimen STC

o

A

W-68-71

W-82-71

W-31-71

W-29-72

W-lO-71

3/8 in. insulating glass 26-28

(average of 2 tests)

7/l6 in. insulating glass 28-30

(average of 2 tests)

1 in. insulating glass 3i+

36
Figure 30. Comparison of sound transmission loss vs frequency data for insulating glass

j with data for single glazing of the same surface density (nominally 2.6 lb/ft ). The dashed curve represents field incidence mass law (see Figure 14 and

accompanying text).

Symbol Test No. Specimen STC

O W-18-T2 3/l6 in. safety glass 31

A W-68-T1 3/8 in. insxilating glass

W-82-T1 (average of 2 tests). 26-28

37
Figure 31. Comparison of sound transmission loss vs frequency data for sealed singlestrength windows with storm sash (at various spacings from primary glazing)

with data for sealed windows, glazed single-strength with storm sash. In

the following table the spacing is the average between panes for upper and

lower sash.

Symbol Test No. Specimen STC_ — W-8-T1 single strength 28-29

W- 33-71 (average of 5 tests)

W-Ul-Tl

W-T6-71

W- 26-72

O w_25-72 storm sash glazed single 29

strength spaced 1/8 in.

A W-37-71 storm sash glazed single 3^

single strength, spaced

2 1/8 in.

W-11-71 storm sash glazed double 38

strength, spaced 3 3/^+

38
which was undamped. Below 2000 Hz, however, the small improvement was due only to its

slightly higher weight.

Sealed Insulating Glass

Averaged data curves for the three thicknesses of insulating glass are shown in Figure

29, with STC values as follows:

The first two of these were formed of double layers of single strength and double

strength glass, respectively, but for most of the frequency range they had TL values equal

to or lower than the single layer alone. The 1 in. insulating glass was formed of 3/l6 in.

safety glass on each side.

According to sound transmission theory, a double wall generally has a higher TL than a single wall of the same total surface weight. This, however, occurs only above a resonance

frequency which is determined by the weight of each layer and their separation. The

greater the weight and the wider the separation, 'the lower is the resonance frequency. At

or near the resonance frequency, the TL is actually lower for the double wall than for the

single wall. Also, the improvement in TL above the resonance frequency for the double wall

may in practice be limited by mechanical coupling between the two sides.

These effects are clearly shown in Figxire 30, where the TL curve of the single-layer

3/16 in. safety glass is compared with that of the 3/8 in. insulating glass having the same total areal density of 2.6 Ib/sq ft. Also shown is the theoretical mass law curve for a limp, single layer material of that weight. The calculated resonance frequency for the

insulating glass is approximately 500 Hz, and the data curves show a wide dip around this

frequency which is 10 dB below the curve for the single layer. In well-isolated dotible

wall structures with wide separation, the TL curve generally rises steeply beyond the mass law line above the resonance frequency, but for the insulating glass this did not occur. This was due largely to the high compressive stiffness of the shallow air cavity and to the

influence of coincidence effects at the highest frequencies. There was also rigid

mechanical coupling around the perimeter of the glass due to the "welded" structure which

may have contributed to flanking sound, transmission

.

For the 1 in. insulating glass shown in Figure 29 both the calculated and observed

resonance frequencies are around 200 Hz, and the rise in TL above resonance is effective

over a larger part of the frequency range. This rise, however, was again severely limited

by the coincidence dip at 25OO Hz.

Sealed Windows with Storm Sash

The data for sealed windows with added storm sash may be grouped as follows:

Window Glazing Storm Glazing _ STC

Single and double strength Single and double strength 29-38

3/8 in. and T/I6 in. insulating Single and double strength 35 - 39

The wide spreads in the above groupings were due, not to the variations in glazing,

but to the wide range of spacings between the window and the storm sash. These varied from

1/8 in. for the aluminum sliding window to 3 3/^ in. for the picture window. The effect of

spacing is shown in Figure 31, where curves are plotted for three single or double strength

storm sashes added to the average of five single strength windows.

These curves agreed well with the predictions of double wall theory. The curve for

1/8 in. spacing was quite similar to those for the insulating glass in Figure 29 and

showed no improvement over the window alone except above 1000 Hz. The calculated resonance

frequency for this spacing was 60O Hz, which was too high for effective double wall

3/8 in.

7/16 in. 1 in.

26 - 28

28 - 30

3k

39
perfoTmance . The calciilated resonance frequencies for the 2 1/8 in. and 3 3/^ in. "spacings were lU5- and 105 Hz, respectively, which agreed fairly well with the observed dips in the

TL curves. In both cases, the TL' curves rose rapidly with frequency above the resonance

frequency, resulting in a 10 to 20 dB improvement over the window alone at all frequencies

above about 500 Hz. The STC values were 3^ and 38, respectively, as compared to 28 to 29

for the window alone.

The highest STC value obtained in the entire window program was 39 for a combination

of a double hung wood window with T/l6 in. insulating glass and a storm sash glazed double

strength at 2 1/8 in. spacing. Although not tested, a considerably higher value could

probably have been obtained by adding a storm sash to the 1 in. insulating glass in the

pictiore window at 3 3/^ in. spacing. The insulating glass alone had an STC of 3^. However, it was ass\amed that the use of storm sash or insulating glass is dictated by'

thermal insulation requirements in common building practice, rather than sound insulation,

and that it woiild be unlikely that a storm sash would be added to a 1 in. thick insulating

glass'.

d. Unsealed Windows

The foregoing data on sealed windows represent their maximum sound insulating

capability. Under normal conditions, of course, this performance is more or less

compromised by sound leakage through perimeter cracks and openings. In all tests of

unsealed windows, the outer frame of the window unit was thoroughly sealed into the wall,

it being assumed that this degree of sealing could reasonably be expected in field

practice. The measured sound leakage, therefore, was attributable only to that which

occurred aroimd the perimeters of movable sashes in various conditions of opening, closing,

and locking.

To provide a reference for interpreting such data, a series was run on accurately

gauged perimeter cracks aro\md the 6 x 5 ft picture window, as shown in Figure 32. The

series was repeated for two picture window sashes having double strength glazing and 1 in.

insulating glass, respectively, in order to show more clearly the relative transmission

thro'ugh the cracks and the glass.

The transmission loss data curves for gauged perimeter cracks around the picture

window are shown in Figure 33 for double strength glazing and Figure 3^ for insulating

glass. Each curve represents the combined transmission through the parallel sound paths of

open crack and glass, the transmission being governed essentially by the weaker of the two

paths. The curves show that oVer most of the frequency range, the transmission is governed

by the crack area. At low fr'equencies , the glass transmission tended to govern, and there

was less difference in transmission due to the various crack areas. In accordance with

theory, the transmission loss should decrease 3 dB with each doubling of transmitting krea,

and the curves agreed quite well with this prediction. The curves also showed that the

transmission through the crack was almost independent of frequency.

The transmission loss of a window with a perimeter crack of known dimensions can be

estimated by assuming that: (l) the transmission loss of the sealed window is much higher

than the window with the crack, (2) the transmission loss of the crack is zero at all

frequencies, and (3) the sound energy transmitted by either the crack or the glass is

directly proportional to the corresponding area. On this basis, the theoretical

transmission loss of the window with crack is:

TL = 10 log (1/k) (T)

where: k = ratio of crack area to window area.

In general, for each of the gauged cracks in Appendix C (Test Nos . W-12-71 to

¥-21-71), the measured values were lower than equation (T) would predict. This point is

discussed in Section 3. 5-

As a further check on the above estimating procedure, the transmission loss curves of

the pictiire window with two cracks of equal area but different lengths and widths are

ho
Figure 32. Detail of framing in filler vail to receive picture window sashes. Strip

A was shinnned out to provide perimeter cracks ranging from 1/32 to l/k in.

125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure 33. Sound transmission loss vs frequency data for 6 x 5 ft picture window,

double- strength glazing, with perimeter cracks of controlled size.

Symbol Test No. Crack Width STC

o W-7-T1 None, complete seal 29

A W-21-71 1/32 in. 25

W-IT-Tl 1/16 in. 21 • W-15-T1 1/8 in. 18

W-16-71 l/k in . 15

hi
70

60

10 _L I

I \ 125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 3h. Sound transmission loss vs frequency data for 6 x 5 ft picture window, glazed

with 1 in. insulating glass, wit'h perimeter cracks of controlled size.

Symbol Test No. Crack Size STC

o W-lO-Tl None, complete seal 31^ A W-20-T1 1/32 in., half perimeter 29

W-19-T1 1/32 in., full perimeter 26 • W-18-T1 l/l6 in., full perimeter 23

W-lU-Tl 1/8 in., full perimeter 19

W-12-T1 l/h in., full perimeter 15

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz Figure 35. Comparison of effect of perimeter cracks of the same area, hut different widths, on the sound transmission loss vs frequency for a 6 x 5 ft picture window,

glazed with 1 in. insulating glass. The dashed horizontal line corresponds

to the theoretical transmission loss, hased on the ratio of crack area to window area, assuming the transmission loss of the crack is 0 dB.

Symhol Test No. Crack Size STC

O W-lU-Tl 1/8 in.^ full perimeter 19

A W-13-T1 ' 1/U in. half perimeter l8

1+2
compared in Figure 35- It is shown that there is no significant difference between the two

tests and generally good agreement with the theoretical transmission loss.

The above equation for the transmission loss of a window with perimeter cracks can he

put in the form:

TL = 10 log ^1 (8)

where: d = crack width, in.

A = window area, sq ft

L = total crack length, ft

This is plotted in Figiire 36 which can he used either to estimate an equivalent crack

width from measurements of transmission loss or to estimate the transmission loss from a known crack width, knowing in either case the window area and sash perimeter. The latter

would he the total crack length for double hwag or multiple sash units. It must also be

known that the measured transmission loss is much lower than that of the sealed window. As

noted above, this would generally be true at the higher frequencies.

As an example, compare the data in Appendix C for the 3 x 5 ft wood double hung

window, glazed insulating glass, sealed (Test No. W- 31-71) versus normally closed and

unlocked (TestKo. W-25-71)' Above 1000 Hz, the transmission loss of the sealed window

ranged from 27 to hO dB, and for the nonnally closed window 21 to 29 dB with an average of

about 2h dB. The ratio A/L for total sash area to total crack length of both sashes

(counting the joint between sashes only once) was calculated at about 0.7- Referring to Figure 36, a transmission loss of 2h dB at A/L =0.7 would resixlt from an equivalent crack

width at all sash perimeter joints of .037 in. or slightly over 1/32 in.

Illustrative data on the effect of sealing only the horizontal joints of this window

are given in Test Nos. W-23-71 and W-35-71 in Appendix C. S\mmiarized test data and test

number references for gauged openings in the other windows are listed in Table C-5.

Probably a more typical condition in practice would be a fully closed window either

locked or unlocked rather than one partially open by a slight amount. Accordingly, all

windows in the program were tested both locked and unlocked as well as fully sealed. In

some types of operable window, closing and locking or latching were accomplished together

so that an unlocked condition could not be tested separately.

An overall comparison of all of the test data for sealed versus unsealed windows is

shown by the envelopes of data in Figure 37. The vmsealed windows were all closed tight

and either locked or unlocked. The lower limit of the envelope for the \insealed windows

corresponded almost entirely to the data for the aluminum casement window unlocked, having

an STC of 17 (Test No. W-20-72). This window had no weatherstripping of any kind. The

same window locked showed a 21 STC (Test No. W-21-72) . Omitting the 'envelope data for the

imlocked window, there was an average difference of about k STC between the two envelopes,

with slightly more difference at the high frequencies and less at the low frequencies.

Illustrative data for a few windows are shown in Figures 38 and 39. The differences

between sealed and unsealed units were most pronounced at the high frequencies , especially

for the insiilating glass which has higher transmission loss at high frequencies than single

or double strength. There were no consistently large differences between the locked and

the unlocked condition, -although there was quite an erratic spread of data in the highest

frequencies. The large dip at i+000 Hz for the unlocked window in Test No. W-25-71 could be

due to resonance phenomena as are discussed in Section 3.5.

h3
40

D

o

COz

<

oc

I I I I I 1—I—I I I I I I

1 r

A = SURFACE AREA,

L = TOTAL CRACK LENGTH, ft

'III! J I

I I I I I I .005 . .01 .02 .05 .1 .2

EQUIVALENT CRACK WIDTH, d, in.

Figure 36. Theoretical sound transmission loss of surface with cracks, assuming the

sound transmission loss of the sealed surface is at least 10 dB higher than

that of the surface with cracks (see text).

w 50 -

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 37- Comparison of the envelope (corresponding to STC 26-3^) of sound transmission

loss vs frequency data for all sealed windows with the envelope (STC 17-30) of

data for all unsealed windows, locked and unlocked.

kk
125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure 38. Comparison of sound transmission loss vs frequency data for sealed and

unsealed windows, glazed single-strength.

Symliol Test' No. Specimen STC

same as in sealed (average of 5 Figure 31 tests) 28-29

O W-7U-TI wood doutle-hung , locked 26

A w_75_7i wood double-hung, \mlocked 26

W-23-T2 alumin\am sliding, latched 2k

45
Figure 39. Comparison of sound transmission loss vs frequency data for sealed and unsealed

windows, glazed 7/16 in. insulating glass.

SymTjol Test No. Specimen STC

W- 31-71

W-29-72

sealed (average of 2 tests) 28-30

o W-2U-71 wood doutle-hung, locked 26

A W-25-71 wood double-hiing , 'unlocked 22

W-27-72 al-uminum single hung,

locked

27

W-28-72 aluminum single hung,

unlocked

25

46
e. Combinations of Windows in Walls

Complete test data for the four combinations' of the 6 x 5 ft picture window in two

walls are shown in Figure ko to k3- For each combination of wall and window, the measured

transmission loss data curve for each component is shown on the charts. Also, on each

chart is shown the calculated transmission loss of the combination, this calciilation being

made using equation (h) with only two areas, that of the wall and that of the window, being

used.

An example of the application of this approximation is shown in the c\arves of Figure

k2 where the window having the minimum transmission loss was placed in the wall having

maximum transmission loss. Even though the window area was much less than the remaining

wall area S^, the transmission coefficient of the window was so much greater than that of

the wall that the ratio (t^S^)/(t S^) was greater than 10 at almost all frequencies. As discussed in Section 3.1., in sucn a case the transmission loss of the combination should

exceed the transmission loss of the window by the amount 10 log (S/S ). For corresponding

areas of 126 and 25.6 sq ft, respectively, the excess is T dB. It will be seen in Figure

k2 that the calculated curve of the combination lies 7 dB above the measured curve of the

window over nearly all of the frequency range. For the other combinations where there was

less difference between the transmission loss of the window, and that of the wall, the

complete formula in equation (h) was used. In every case, the transmission loss of the

combination fell between the transmission loss values of each component.

3. 5. Comparison of Results with Those of Other Investigations

3. 5. 1. Walls No data were found in the literature on exterior walls similar in construction to those tested during the present investigation. However, it was felt to be useful to compare the effects of resilient channels and cavity insulation with corresponding data on interior walls. Figure hk repeats the data shown in Figure l8 for the wood-siding

wood-stud, exterior wall, with and without cavity insulation and with and without resilient

channels. Figure U5 presents the data of Northwood [61] on two-leaf walls with 1/2 in.

plasterboard on either side of nominal h in. studs; curves 1 and 2 correspond to 2 x U in.

wood studs on 2k in. centers while curves 3 and h correspond to 3 5/8 in. steel channel

studs on 2k in. centers (the steel channel studs should have provided roughly equivalent

vibration isolation to that provided by the resilient channels in the case of the wood

siding, wood stud exterior wall). Several similarities and differences between Figures kk

and U5 can be pointed out. Since both sides of the plasterboard walls were of identical

construction, the high frequency coincidence dips for these walls are much more pronounced

than are those for the exterior walls. The improvement due to resilient channels plus

cavity insulation is about the same for the interior and the exterior walls . Since both

sides of the plasterboard walls are identical, they are very efficiently coupled by the

stiffness of the air in the cavity so that resilient channels, without cavity insulation,

do not produce as much improvement for the interior walls as they do for exterior walls.

Since the inner and outer surfaces of the exterior walls are of different construction, the

coupling through the air cavity is not veiy efficient so that addition of cavity insiilation

alone does not provide much improvement for the exterior walls. Ver and Holmer [l2] give

procedures for estimating the effectiveness of different procediores for vibration isolation

between the two sides of double walls.

3. 5. 2. Doors

The data presented here are restricted to sealed or tightly gasketed doors . The

effects of cracks are discussed in Sections 3.5.^. and 6.1.

Figures k6 and U7 present data on a total of eight solid core wood doors having areal

densities ranging between 3.3 and T.O Ib/sq ft. The data (Test W-9I-TI) from the present

investigation are shown in both figures to facilitate comparisons. Although the sovmd

transmission loss curves from the several investigations differ _ somewhat at low and high

frequencies , the STC values are all within a range of +3 around the value obtained in the

present investigation.

hi
70

60

O

w 40

"S 30

20

10 _L _L

Figure hO.

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz Comparison of measured sound transmission loss vs frequency data for a 6 x 5 ft

picture vindow, glazed single strength, in a wood siding wall with that predicted from the transmission losses and areas of the wall and window (window area

= 25-6 sq ft, wall plus window area = 126 sq ft).

Figure hi.

Symbol - Test No. o

A

Specimen STC

W-5i+-71 wall alone 39

W-8-T1 window alone 28

W-5T-T1 combination, measured 35

combination, calculated 3^

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz Comparison of measured sound transmission loss vs frequency data for a 6 x 5 ft

picture window, glazed 1 in. insiilating glass, in a wood siding wall with that

predicted from the transmission losses and areas of the wall and window (window area = 25.6 sq ft, wall plus window area = 126 sq ft).

Symbol Test No. Specimen STC

O W-5U-T1 wall alone 39

A WrlO-71 window alone 3h — W-58-TI combination, measured 38

combination, calculated 38

US
Symbol Test No. Specimen STC

O y-kU-H vail alone 56

A W-8-T1 window alone 28

W-U9-TI combination, measured 35

I • combination, calculated 35

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure h2. Comparison of measured sound transmission loss vs frequency data for a 6 x 5 ft picture window, glazed single strength, in a. brick veneer wall with that

predicted from the transmission losses and areas of the wall and window

(window area = 25-6 sq ft, wall plus window area = 126 sq ft).

Symbol Test No. Specimen STC

O W-i+i|-Tl wall alone 56

A W-lO-Tl window alone 3^^ W-^8-Tl combination, measured 39 ——• combination, calculated ^+1

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure U3. Comparison of measured sound transmission loss vs frequency data for a 6 x 5 ft picture window, glazed 1 in insulating glass, in a brick veneer wall with

that predicted from the transmission losses and areas of the wall and window

(window area = 25.6 sq ft, wall plus window area = 126 sq ft).

h9
125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure 44. Sound transmission loss vs frequency data for wood-siding, wood-stud, exterior

walls. The data are from the present investigation and correspond to walls

with or without resilient channels and with or without cavity insulation.

Cavity Resilient

Curve Test No. Insulation Channel STC

1 W-1+-T2 no no 37

2 W-5U-TI yes no 39

3 W- 56-71 no yes 1+3 k W-55-71 yes yes 1+7

50
CDo

co- coO_iz

g

CO

CO

COz

<

125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure 45. Sound transmission loss vs frequency data for plasterboard interior walls.

The data are from Northwood [6l] and correspond to walls with wood or metal

studs and with or without cavity insulation.

Curve Wall No. Cavity

Insiolation

Metal

Channel Stud

STC

2.03

2.13

2.0k

2.1k

no yes

no yes

no

no yes

yes

35

ko

36

kh

51
co" o

COz

<

70

60

50

2 40

30

20

10 J L J L 125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure 46. Sound transmission loss vs frequency data for solid core wood doors.

Curve Reference

Test or Specimen No. STC Areal

Density

-2

present

investigation W-9I-71

[25]

[25]

[25]

632

6IT

616

30

30

28

30

lb ft

3.91

5.6

7.0

52
03u

C/j" t/> O

_iZ

g

CO<

I70

60

50

40

30

20

10

1

—

1 1 1

1

1

-

3 -

1 4 - '^r/

^ 3

1

1 1 1 1 1 125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure h'J . Sound transmission loss vs frequency data for solid core wood doors

Curve 1 is the same as in Figure U6.

Curve Reference

Test or Specimen No. STCAreal

Density

lb ft

1 present

investigation W-91-T1 30 3.91

2 [62] 27 31 1+.52 3 [28] T031 33 3.28

h [28] 7111-3 27 3.69

5 [31] p. 100 29 1

-2

53
Figure hQ presents data on four hollow core doors having areal densities from 1.2 to

2.3 Ih/sq ft. Again there are significant differences at low and high frequencies but the

STC values are essentially identical.

3. 5. 3. Windows

Marsh [63] has given a comprehensive review of the literature on the sound transmission loss of glass, including a compilation of tabulated data. Wherever possible, data

in this section were taken from her review rather than from the original so\irce.

Probably because most measurements of the sound transmission loss of glass pres\imably

have been taken in support of engineering solutions for situations where better-than-usual

sound isolation was required, most of the data reported by Marsh are for glass much thicker

than the single- and double-strength glass used for most of the windows examined in the

present investigation. "

Figure ^9 shows a comparison of the envelope of sound transmission loss data, from the

present investigation, for sealed windows having double-strength glazing (nominally 1/8

in. ) with the envelope of data for sealed windows having 3 mm glazing as reported in Table

Al of Marsh [63]. The agreement is not good at low frequencies, where it is difficult to make accurate sound transmission loss measurements. Insofar as overall performance is

concerned, the present data fall in the upper end (STC 29-31) of the range of data cited by

Marsh (STC 26-31).

Figure 50 shows a comparison of the envelope of sound transmission loss data, from the

present investigation, for sealed windows having single-strength glazing (nominally 3/32

in) with the envelope of data for three sealed windows of similar thickness as reported in

the literature [62,63]. The present data correspond to STC 28-29 while the literature data

correspond to STC 26-28.

Marsh [63] foimd that the solid line shown in Figure 51 represented the mean soimd

transmission loss ( not the Sound Transmission Class) for sealed windows over the frequency

range from 100 to 3150 Hz as a function of glass thickness . The dashed lines 3 dB above

and below the solid line encompass about 95 percent of the literature data which she used.

The solid circles indicate the average and range of the data from the present

investigation.

Patil [6k] reported a nimiber of recent STC determinations made at Riverbank Acoustical

Laboratories on glass of various thicknesses. These results are compared, in Figure 52,

with the average and range of data on single- and double-strength glass from the present

investigation. The present data lie from 1 to 3 STC-units above a mean cvocye through the

Riverbank data.

In the present investigation it was found that the Sound Transmission Class for a given glass thickness was essentially independent of the size of the individual panes and

of the type of window. Since glass has very low internal damping, one would expect that

resilient mounting of the glass, which was not examined in the present investigation, would

improve the sound transmission loss, especially near the coincidence region. Marsh [63]

discusses this point briefly. The work of Utley and Fletcher [65-66] and Cops, Myncke, and

Lambert [67] provides considerable useful information on the influence of edge damping.

Figure 53 compares -the results from the present investigation on l/k in. laminated

glass, having an internal damping layer, with data on nominally identical glazing as reported by Marsh [63]. The data are seen to be very similar. In the present investigation an STC of 3^ was found while the data reported by Marsh correspond to approximately

STC 32-33. Patil [6k] reports a value for similar glazing of STC 3^.

Of the pre-fabricated insulating glass units tested in the present investigation,

literature data on comparable units were found only for the 7/l6 in. insulating glass (two

1/8 in. panes with a 3/l6 in. air space). In Figure 3k, the solid curves represent the

envelope for the two units tested (STC 28 and 30) while the dotted curves represent the

envelope of three windows reported by Marsh [63].

5h
70

60 -

SO -

QQ

TJV)

(/) O

_iz

o 40 -

<

30 -

20 -

10

125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Fig\ire k8. Sound transmission loss vs frequency data for hollow core wood cores

.

Test or Areal

Curve Reference Specimen No. STC Density

-2

It ft

1 present

investigation W- 9 3-71 21 1.23

2 [25] 63h 20 1.9

3 [62] 26 20 1.1+3 h [28] TO83-I 20 2.25

55
Figure hg. Sound transmission loss vs frequency data for sealed windows, of various types

and sizes, with double-strength (3 nm) glazing. The solid curves represent

the envelope of data obtained in the present investigation (Tests W-7-71, W-32-71,

W-3U-71, W-6i+-71, W-66-71, and W-21-72). The dotted curves represent the envelope

of data, on sealed windows only, from Table A5 of Marsh [63] (the sets of data

included are the 2nd and 3rd of Aston, the 1st of Wooley, and the 1st, 2nd and

kth of Saint-Gobain)

.

56
70

60 -

Figirre 50. So\ind transmission loss vs frequency data for sealed windows, of various types

and sizes, with single-strength glazing. The solid curves represent the envelope

of data obtained in the present investigation (Tests W-8-T1, W-33-T1, W-lil-Tl,

W-TS-TIj and W-26-T2). The dotted c\irves represent the envelope of the following data: Brandt (2 mm glass) and Libhey-Owens-Ford (3/32 in. glass) from

Table A6 of Marsh [63]; caulked steel frame casement window (3/32 in. glass)

from Bishop and Hirtle [62].

57
40

^ 35

w"

COO

_lg

to

S2 30

CO<

GLASS THICKNESS, in. 3/32 1/8 3/16 1/4 3/8 1/2 3/4

25

20

T

GLASS THICKNESS, mm

Figure 51- Mean sound transmission loss (arithmetic average of the values over the range

100 to 3150 Hz) of sealed windows vs glass thickness. The solid line is that which

was fitted to literature data "by Marsh [63]- . The dashed lines enclose all but

two of the data points she used to derive the solid line. The solid circles

represent the average and range of data on single- and double-strength glazing

from the present investigation.

<o

zo

CO<

t-o

z

oCO

40

35

30

25

20

GLASS THICKNESS, in.

3/32 1/8 3/16 1/4 3/8 1/2 3/4 1 T T "1 r

ST C = 23 + 10.8 LOG.n d

(d is thickness, mm)

I _L _L

3 4 6 8 10 GLASS THICKNESS, mm

20 30

Figure 52. Soimd Transmission Class of sealed windows vs glass thickness. The triangles

and the line fitted through them represent the data reported by Patil [6k].

The solid circles represent the average and range of data on single- and

double-strength glazing from the present investigation.

58
m

o

V)

COO

V)w

V)z

<

125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure 53. Sound transmission loss vs frequency data for l/U in. laminated glass with an internal damping layer. The solid curve represents the data from the present

investigation (Test No. ¥-22-72) vhile the dotted curves represent the envelope

of data from Table A8 of Marsh [63] (the two sets of data are that of Pilkington

Bros, and the 1st of Libhey-Owens-Ford)

.

59
Figure 5^- Sound transmission loss vs frequency data for T/16 in. insulating glass units

consisting, nominally, of two 1/8 in. panes of glass separated "by a 3/l6 in.

air space. 'The solid curves represent the envelope of data obtained in the

present investigation (Tests W- 31-71 and W-29-T2) . The dotted curves represent

the envelope of data from Tahle Bl of Marsh [63]. (the sets of data included

are the 2nd of Wooley and the two of Saint-Gobain)

.

60
The solid curve in Figiore 55 represents the data for the single-strength picttire

window with a double-strength storm sash spaced. 3,3/^ in. away. The dotted curves represent the envelope of data for three windows reported hy Marsh [63]'. All fo\ir windows

had an STC of 38.

Curve No. 1 in Figure 56 represents the average sound transmission loss for three

double-hung windows with storm sashes an average distance of either 2 1/8 or 2 3/U in. (5^+ or TO mm) away. Since the upper and lower window sashes were not the same distance from

the storm sash, comparisons with literature data are not very meaningful. Curves 2 and 3 correspond to literature data with spacings of 32 and 75 mm, respectively. Curve k corresponds to literature data with a spacing of 51 mm. Curve 5 is for a douhle-hung

window with the upper and lower sashes spaced different distances from the storm sash.

These spacings were very similar to those in the present investigation. However, the poor

high frequency performance indicates that this window may not have been tightly sealed.

Marsh [63] tabulates data on a large number of double-glazing situations and dis.cusses

these data in some detail. DeLange [68] gives data (measured under conditions wherein the

sound impinged on the windows from discrete directions) on a variety of constructions and

discusses the use of such data. Sharp [3l] gives data on a few windows having high sound

transmission loss.

3. 5. 4. Cracks and Openings

Data reported by Marsh [63], Bishop and Hirtle [62], and others are in qualitative

agreement with the results of the present investigation as regards the influence of cracks

and openings on the effective so\ind transmission loss of doors and windows. These data all

indicate that such leaks can seriously reduce the sound isolation at medi\im to high

frequencies. In the absence of quantitative information on the size of such leaks, there

is little or no point in quantitative comparisons of soimd transmission loss data since

different windows or doors of nominally the same construction may differ considerably in

the size of cracks and openings. For this reason, further discussion of the effect of

normally occurring cracks is deferred until Section 6.1, where correlations are made with

the resvilts of air leakage tests. The remainder of the discussion in the present section

is limited to those tests where controlled-width cracks were intentionally introduced.

There are many papers in the literature which address the problem of wave propagation

through openings in very thin walls. Papers which are directly relevant to sound transmission through finite thickness walls include [69-82]. The work of Gomperts [T6,7T] and

Gomperts and Kihlman,[78] is most directly applicable to the tests, in the present

investigation, on windows with cracks of known size.

Figure 57 displays the sound transmission loss, computed from equation (69) of

Gomperts [76], for slits in the middle of a wall separating two reverberation chambers.

The lower figure shows the results for 1/32- in. and l/k in. slits in a 2 in. thick wall

while the upper figiore corresponds to slits of the same widths in a it in. thick wall. (The

abcissa in this figiare represents continuous frequency rather than discrete l/3-octave

frequency bands as used in previous figures). For a given slit, the sound transmission

loss increases monotonically with frequency until the wavelength of sound decreases to a value approaching twice the wall thickness. The resonances occur when the frequency is

such that the wall thickness is approximately equal to an odd number of half-wavelengths of

the soimd.

For measurements made in 1/3-octave frequency bands, as was done in the present

investigation, the sharp resonances shown in Figure 57 could not be observed. Figure 58

compares the ctirve (from Figure 57) for a 1/32 in. wide, 2 in. deep slit with the corres- ponding curve averaged over a l/3-octave frequency band by numerical integration of

Gomperts' equation (69). It is seen that the resonance dips are neither so sharp nor so deep as in the pure tone case.

Gomperts' equation (69) does not include the effects of energy loss due to viscous

flow in the slit. As shown in his later paper [77] 5 this will further increase the

measured sound transmission loss at frequencies near to the resonances

.

61
T3in

COO

CO

CO<

125 250 500 1000 2000 4000

BAND CENTER FREQUENCY. Hz

Figure 55- Sound transmission loss vs frequency data for double glazing with a nominal h in.

separation between the two panes. The solid curve represents a 6 x 5 ft picture

window glazed single strength (2.1+ mm) with a double strength (3mm) storm window

spaced 95 mm (3 3>/h in.) away (Test W-11-71). The dotted ciirves represent the

envelope of data, from Table C2 of Marsh [63], for 3 mm panes separated by 100

to 102 mm (the sets of data are the first listed for each of the following:

Aston, Ingemansson, and Woolley)

.

62
OQ"Dto

COO

-Jz

g

wCO

COz

<

125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figvire 55. Sound transmission loss vs frequency data for double glazing with an average

nominal spacing of about 2 to 3 in. between the two panes.

Curve Reference Comments STC

present

investigation

[63, Table B2]

Fasold

[63, Table Cl]

Fasold

[63, Table Cl]

Aston

average of Tests W-36-T1, 36,3^,36

W-3T-T1, and W-79-T1 (5^^ or TO mm air space)

[62]

3 mm glazing with 32 mm

air space

3 mm glazing with 75 nun air space

3 mm glazing with 51 nim air space

Test 15, 3/32 in. glass

with 51 nmi air space at top, 95 mm air space at bottom

l40

1+1+

31+

29

63
125 250 500 1000 2000 4000

FREQUENCY, Hz

Figure 57- Theoretical sound transmission loss vs frequency data for slits in the middle

of a wall between two reverberant rooms, as computed from eq. (69) of

Goraperts [T6].

6h
125 250 500 1000 2000 4000

FREQUENCY, Hz

Figure 58. Theoretical sound transmission loss vs frequency data for slits in the middle of

a wall "between two reverherant rooms. The lower curve represents pure tone

behavior while the upper curve corresponds to values averaged over a frequencyband that is 1/3 octave in width. The lower cxirve was computed from eq. (69)

of Gomperts [T6] while the upper curve was derived by numerical integration of

the transmission coefficient corresponding to the lower curve.

65
Figures 59 through 62 compare the experimental data for the so\and transmission loss of

cracks of known width around picture windows with the predictions of equation (69) of

Gomperts [76]. The experimental data were calculated, using equation (U) of the present

report, from two tests — one with the crack present and one with the window sealed. As

shown in Figure 32, for cracks smaller than ±/k in. in width, the actual crack consisted of

two cracks in series — a l/U in. wide crack "between the sash and the framing and a 1/8,

1/16, or 1/32 in. crack between strip A and the framing. For calculation of "both the data

points and the theoretical curves in Figures 59-62, an effective crack width was used,

namely, the width of a uniform crack that would contain the same volume of air as the

actual crack.

Further reference to Figure 32 indicates that the proper values for the effective

depths of the cracks are not obvious. Since it was foiind empirically that effective crack

depths about 25 percent greater than the combined thickness of the sash and of strip A gave

theoretical resonance frequencies in good agreement with the experimental data, those were

the depths used for the two theoretical curves in Figtires 59-62. The dotted curves in

these four figures were computed in the same manner as the upper curve in Figure 58; they

correspond to the transmission coefficient, averaged over a 1/3-octave band, for a slit in.

the middle of a wall between two reverberant rooms. Since the window was located in a recess in an otherwise thick wall, the solid curves were also generated; they correspond to

a slit at the edge of a wall between two reverberant rooms

.

Considering the rather complex geometry of the slit, framing, and filler wall, the

agreement between the experimental data and the theoretical curves in Figure 59 is perhaps

better than might have been expected. At very low frequencies, the geometry irregularities were small compared to the wavelength of sound so the slit behaved as if it were in the

middle of a smooth wall between the two reverberant rooms (corresponding to the dotted

curves). As frequency increased, the wavelength decreased so that the recesses on either

side became effective in making the slit behave as if it were at the edge of the wall

(corresponding to the solid curves). At high frequencies, the irregular geometry leads to much less pronounced resonances that are calculated for a slit in a smooth wall. As the

slit width decreases, the experimental data at very low and very high frequencies lie

fvirther and further above the theoretical curves. Preliminary analysis indicates that this

is at least partially due to energy loss by viscous flow through the narrow slit between

strip A and the framing (see Figure 32).

Discussion of other experimental data on leaky windows is deferred until Section 6.1.

In general, openings severely reduce the sound isolation otherwise provided by

windows. However, when no other means of ventilation is available, the work of Ford and

Kerry [83] and Kerry and Ford [8U] is of particular interest since it shows that double

glazing with staggered openings can be rather effective even for fairly large openings

.

66
125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure 59- Comparison of experimental results and theoretical predictions for the sound

transmission loss of l/k in. cracks around picture vindovs . The data points in

the upper portion of the figure are from Test W-I6-TI and the average of Tests

W-T-Tl and W-9-T1; those in the lower portion are from Tests W-12-T1 and W-10-71.

Solid symlDols indicate that the transmission loss of the sealed window was at least 9 dB greater than that of the leaky window, while half-filled symhols

indicate a 6 to 9 dB difference and open symbols a 3 to 6 dB difference. If the

effect of the crack was less than 3 dB for a given frequency band, the data

are not plotted. The dotted curves were calculated from equation (69) of

Gomperts [T6] averaged over a 1/3 octave band, for a slit in the middle of a wall; the solid curves were calculated in a similar manner but correspond to a slit at the edge of a wall between two reverberant rooms. The effective _ depth

of the slit was taken as k.^ in. for the theoretical calculations in the lower

figure and as h.O in. for those in the upper figure.

67
125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure 60. Conrparison of experimental results and theoretical predictions for the sound

transmission loss of 1/8 in. cracks around picture windows. The data points in

the upper portion of the figure are from Test W-15-T1 and the average of Tests

W-7-T1 and W-9-T1; those in the lower portion are from Tests W-I8-TI and W-lO-Tl.

The effective width of the slit was taken as the uniform width which would

contain the same mass of air as the actual slit (which consisted of two segments

of different widths. (Otherwise, as in Figure 59)-

68
125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure 6l. Comparison of experimental results and theoretical predictions for the sound

transmission loss of l/l6 in. cracks around picture windows. The data points in

the upper portion of the figure are from Test W-IT-Tl and the average of Tests

W-T-71 and W-9-71; those in the lower portion are from Tests W-18-71 and W-10-71

(otherwise, as in Figure 6o)

.

§9
125 250 500 1000 2000 4000

BAND CENTER FREQUENCY, Hz

Figure 62. Comparison of experimental results and theoretical predictions for the sound

transmission loss of 1/32 in. cracks around picture windows. The data points

in the upper portion of the figure are from Test W-21-T1 and the average of Tests

W-T-Tl and W-9-T1; those in the lower portion are from Tests W-19-T1 and W-lO-Tl.

(otherwise, as in Figure 6o).

TO
4. Thermal Transmittance and Resistance Tests

4. 1, Background

In general, architects, engineers, builders and others who might use the data and

information in this report have a more thorough backgroimd in heat transfer than they do in

acoustics. Accordingly, less backgroixnd information is given here than in the preceding

chapter. References are given, however, for those who seek additional material concerning

the concepts of thermal insulation of buildings.

The general concepts and procediires for estimating heat transmission through building

elements are covered in the ASHRAE Handbook of Fundamentals [ 85 ] ; additional information is

given in the ASHRAE Handbook and Product Directory — Systems [86]. Other useful references

include [ 87-97 ] • The National Bureau of Standards has published a number of technical

papers and reports [98-112] and consumer-oriented publications [113-11^ ] relative to heat

gain or loss from buildings.

The following discussion is intended to briefly define those terms used in this

section of the report. For additional definitions, see [II5].

The total heat flow through a wall from an air space on one side of the wall to the

air space on the other side of the wall is usually computed from

Q = SU(T^ - T^), (9)

where S is the total area (ft = sq ft)-^ of the wall, T^ and T are the average air

temperatures (°F) on the hot and cold sides, respectively, and 6 is the thermal

-1 -2 -1

transmittance or over-all coefficient of heat transfer (Btu hr ft °F = Btu/(hr sq ft

°F). Note that for a non-homogeneous wall, U is an average value (per unit area) for that

particular wall. The thermal transmittance can, in principle, be computed from the thermal

-1 2 conductance , C, (Btu/(hr sq ft °F)) or the thermal resistance , R, (Btu hr ft °F = hr sq

ft °F/Btu) )—^ of the wall and the surface coefficients (f^, f^ ) on either side of the

wall:

(10)

The total temperatiare difference between the air spaces on either side of the wall is

the sum of three components:

y I — The units given in parenthesis are customary U. S. Engineering units. Metric

equivalents are given in Appendix A. —'^"Terms ending in "-ance" generally designate properties of a particular object

and thus may depend not only on its component elements, but also on its size,

shape, or surface conditions. Strictly speaking, the terms "conductance",

"transmittance," and "resistance" apply to an object having a particxalar and

individual total or whole area of cross section through which the heat flows.

However, in general practice and usage, it is convenient to refer to unit area conductance or resistance where the unit area is considered to be representative

of the whole area of cross section. "Conductance (or Resistance) per Unit Area"

could be used, but in ordinary usage, this is shortened to "Conductance" or "Resistance" with the unit area concept understood." [115 ].

71
h

c where T^' and T^' are the average temperatures of the hot and cold sides of the wall,

respectively. These three equations may be thought of as the defining equations for R, C,

f^, and f . As defined above, R is the "surface-to-surface resistance" in that it does

not incluSe the resistance of the "air films" on either side of the wall. The "air-to-air

resistance", which does include these "films", is simply the reciprocal of the thermal*

transmittance , U.

When a wall is penetrated by windows, doors, or other parallel heat paths, the

effective thermal transmittance of the composite wall is related to the transmittances of

the several components by

US + US + us + . . . U = — — (12) S^ + S^ + S^ + . .. ' ^^^^

where U is the transmittance for the element of area S , etc. , and the summation is over

11/ all areas of the partition. — Equation (12) may be written in terms of resistances as

1 _ f^A^VVlV^B^

R S (13)

where S = S^ + S^ + S^ + ... is the total wall area corresponding to R. Equations (l2) and

(13) assume independent parallel heat flow along the several paths and ignore exchanges of

heat among the several paths. Furthermore, it is important to note that

equations (12 and (13) correspond to heat flow between isothermal surfaces . Since

"U-values" typically correspond to heat transfer from one essentially isothermal body of

air to another essentially isothermal body of air, equation (12) usually may be used with

some confidence. However, caution must be used in applying equation (l3) . When a well-insulated wall is penetrated by a door or window whose thermal resistance is much less

than that of the wall, the surface-to-surface temperature difference through the

penetration can be much less than that through the wall so that use of equation (l2) to

calculate surface-to-s\irface resistances can lead to very large errors.

Pressure differences between the inside and outside of a building can result in a flow

of air through cracks and openings. The heat flow associated with this air flow is equal

to the product of the mass flow rate of air, the specific heat of air, and the temperat\:ire

difference through which the air must be heated or cooled. In the customary engineering

units being used in this report, this heat flow is given by

Q = 1.08 V (T^ - T ) Btu hr"-"-, (lU) a he 3 —1

where V is the volumetric flow rate at standard conditions (standard ft min = scfm) ; see Section 6.2 for further discussion. The apparent thermal transmittance of a wall either

can be computed from the total heat flow or from the difference between the total heat flow

and that associated with the mass flow of air through leaks. Care must be taken to avoid

confusion between these alternative approaches. —^cf. equation (U).

12
4. 2. Experimental Procedure

The thermal resistance of walls and other structure's may he calculated with some success from values of the thermal conductivity of the component materials as measured

according to standard methods [ll6,117]. However, for non-homogeneous walls, it is

preferable to make direct measurements on the construction of interest, using, for example,

a guarded hot box [ll8]. Earlier NBS publications relevant to this type of measurement

include [ 98-100 ]

.

ASTM C236-66 (1971) covers the measurement of the thermal, transmittance and thermal

resistance of non-homogeneous panels representative of such constructions as the walls,

roofs, and floors of buildings. The essential principles and the general arrangement are given but the final details of the apparatus and test procedures are the responsibility of

the tester so as not to restrict the configuration of the 'specimen to be tested. The

method determines the total flow of heat from the warmer to the cooler side through the

test area demarcated by the metering box and may be applied to any construction for which

it is possible to build a reasonably representative panel.

12/ Thermal transmission testing was performed using a facility,— previously described

by Mumaw [ll9]j w];iich was designed especially for evaluation of heat transmission, air ,, infiltration, and heat transmission in the presence of air infiltration through full-size

building wall sections. The equipment was patterned after the ASTM C236 Guarded Hot Box

but modified to operate on a calibrated box principle. It was operated within a controlled

environment maintained at 75'°F5 50^ relative humidity, and consisted of two massively

insulated chambers, one controlled at reduced temperatures down to -30 °F and the other

normally controlled at room temperature (75 °F) in which metered power consumption was measured. The 9 x lU ft specimen, constructed on a movable test frame, was positioned and

clamped between the two chambers for a test. See Figure 63.

With the specimen in this position, conditioned, temperature-controlled air was circulated past the exposed wall surfaces using small blowers and an air handling system

designed to provide even flow across the specimen. The air, circulated in the direction of

natural convection, moved at a rate of ^0 to 50 ft/min.

The rate of heat flow through the wall is equal to the net energy input to the hot

side, after correcting for wall losses of the hot box. Electrical input energy was measured using a precision watt-hour-meter. The heat losses by conduction through the box

side walls were determined using a heat meter technique. Subtracting the wall correction

from the electrical energy yielded the net heat flow through the test wall. Temperature

measurements for the various surfaces were obtained using copper-constantan thermocouples

referenced through a constant temperature reference system.

Auxiliary equipment (see Section 5.2) was used to provide a constant air flow (from

cold side to hot side) rate throiagh the specimen during some of the thermal tests.

After completion of selected thermal tests, the heated metering side of the thermal test

apparatus (normally maintained at 75 °F for testing) was removed, exposing the test wall

to the ambient room conditions which were controlled at 75 °F, 50^ relative humidity. The

test wall was then observed , with a Barnes/Bofors Model T-101 (modified by supplier to T-102)

real-time infrared camera—^' to obtain additional information regarding principal heat flow

paths

.

—^^The facility was designed and built by Owens-Corning Fiberglas Corporation prior

to performance of the contract work described in this publication. —13/The equipment used is commercially available. The techniques used, however, were developed by Owens-Corning Fiberglas Corporation prior to performance of the

contract work described in this publication.

73
COLD CHAMBER TEST FRAME HOT CHAMBER

EVAPORATOR

METERING

ORIFICE

Figure 63. Schematic section of calibrated hot box facility used for thermal tests. Com- ponents are described in the text and by Mumaw [119 ].
The infrared" camera normally operates with 12.5° vertical by 25° horizontal field of

view. This particular high resolution camera has a scanning rate of two frames per second,

with each frame presenting 225 bits of information on each of l6o lines. The data are presented on the cathode ray tube of an oscilloscope as a gray scale picture with higher

intensities representing higher temperatures and lower intensities representing lower

temperatures. In addition, the camera is equipped with a single line scan option. This

permits selecting one scan line and presenting a temperature profile on the y-axis with

temperature proportional to pifl.9e laeight.

To provide more accurate temperature measurement with the single line scan, a

conip^rator is used. It has two 8x8 ,in. by l/2-in. thick aluminum plates which are painted to match the emittance of the test wall. They are equipped with thermocouples so that their surface temperatiires can be measured. The plates are thermoelectrically cooled

and controlled to maintain a selectable temperature of approximately 2 °F between them.

The comparator can be placed in the field of view of the infrared camera and used as a calibration. The camera is capable of a resolution of approximately 0.2 °F.

4. 3. Calculation Procedures and Uncertainties

The thermal transmittance between the hot box and the cold box and the thermal

resistance (surface-to-surface) of the wall were conrputed using equations (9) snd (lib),

respectively.

Mumaw [119] has reported on the estimated measurement uncertainties associated with

this apparatus. He estimates that the overall tincertainty is typically less than 1 percent. As in the case of sound transmission, additional uncertainties arise in

computing the performance of a window or door from data obtained in two tests , one on the

composite structui-e with the penetration in place and one on the basic wall. Ho estimate

has been made of the additional uncertainties that may be introduced due to a large air

flow through the test specimen.

4, 4. Results

The thermal transmission tests were limited to wall constructions with the wood

siding and brick veneer exterior finishes. The thermal tests included wooden frame

windows in two sizes and three of the five doors. The doors and windows were tested only

as normally installed without special sealing. In all cases, tests were run both with and

without an imposed pressure difference (either 0.25 or 0.50 in. water, corresponding to a vind

speed of approximately 20-25 or 30-35 mph, respectively) across the test specimen.

Selected data in condensed form listing nomi^ial test conditions and thermal

transmittance values are given in Section h.k.2 below. Complete test data are given in

Table D-1, Appendix D. Section U.i+.l, below gives a very brief summary of the test data

along with certain of the more important conclusions.

4. 4. 1. Summary and Conclusions

The simmarized test data given below are those obtained only for the specific tests

in this program and do not necessarily apply to general types or classes of construction

or products.

1. Installation of 3-1/2 in. Rll insulation between the studs of a wood-siding wood-stud

exterior wall raised the thermal resistance of the wall by approximately a factor of

three.

2. Attaching the interior drywall to resilient channel raised the thermal resistance of

the wall by about five percent above that obtained with the drywall attached directly

to the studs (cavity ins\ilation in both cases).

3. Installation of a nominal 3 x 7 ft door in a 9 x li+ ft insulated wall decreased the

effective (average) air-to-air thermal resistance by 2.1 to k.h hr sq ft °F/Btu in the

absence of an imposed air flow and by 5. it to 9-1 hr sq ft °F/Btu with an imposed

J)ressure differential of 0.25 in. water. A normally installed (i.e. , leaky) storm

door did not provide much improvement.

75
Installation of a window in a 9 x lU ft insijlated wall decreased the effective (average) air-to-air thermal, resistance of the combination by the following amoimts

:

5.

Description of Window Nominal

Window

Area, %

Decrease in Effective Air-to-Air

Thermal Resistance, hr sq ft °F/Btu

without imposed

pressure differential

with imposed ~

pressure differential of 0.25 in.

water

3 X 5 ft wood double-hung

single glazed window, locked

12 5.5 9.2

same window as above, locked,

plus single glazed wood storm

windows

12 3.9 9.7

3 X 5 ft wood double-hung

window, glazed 7/l6 in.

insulating elas'^ Inokpii

12 1^.1+ 10.2

6 X 5 ft wood picture window,

single glazed, divided light

21+ 7.5 7.6

6 X 5 ft wood picture window,

glazed 1 in. insiilating glass,

single light

2l+ 5.6

L

6.6

In the presence of an imposed pressure difference corresponding to a 20-25 mph wind speed, heat transfer through walls with normally installed openable doors anfwlndows was due chiefly to air leakage. wxnuuws

4. 4. 2. Discussion

a . Walls

The results of the nine pairs (i.e., with and without imposed air flow) of tests

conducted on two basic exterior wall constructions are given in Table 1. Seven of the test pairs correspond to wood siding walls with differences in 'sheathing, cavity insulation, and

use of resilient channel. The other two test pairs were on brick veneer walls with and without cavity insulation. For two of the constructions, the test at 0.0 in. water' pressure difference was repeated.

Table 1 includes values for both the air-to-air thermal transmittance and the

surface-to-surface thermal resistance. Both quantities correspond to the total heat flow

through the wall, i.e., no correction has been made for the heat transferred by the mass flow of air. The thermal transmittance values include the surface film coefficients given m Table D-1 (1.2 to 1.8 Btu/(hr sq ft °F) on the hot side and 1.1+ to 3.1 Btu/(hr sq ft °F) on the cold side)

.

Inspection of Table 1 clearly shows the importance of cavity insulation. In the

absence of cavity insiolation, the use of 3/^ in. foamed polystyrene sheathing resulted in

significantly higher thermal resistance than did the use of 1/2 in. wood fiber sheathing

(the improvement would have been proportionately much less if the foamed polystyrene

sheathing had been used in combination with cavity insulation). The use of resilient

channel on the interior side resulted in a small improvement (this would have been larger

for reflective faced insulation). Brick veneer increased the thermal resistance slightly

in the absence of an imposed air pressure difference across the wall but did not lead to as good performance as wood siding when an air pressure difference was present (note, in

Appendix D, the difference in air leakage).

76
Table 1. Thermal transmittance and thermal resistance of various 2 x k in. wood stud walls

with 1/2 in. gypsum board on the interior surface. The nominal mean temperature

was 27. 5 °F. 75 °F hotside, -20 °F cold side.

Description of

Exterior Surface

Description of

Cavity Insulation Test No. PressureDifferential

Effective*

Thermal

Transmittance

( air-to-air)

E f f ec tive-' Thermal

Resistance

(surface tosur face)

Redwood siding

over 1/2 inch

wood fiber

sheathing

None TT-001-71

TT-018-71

TT-019-71

in. water

0.

0.0.50

Btu hr"^

ft °F

^

0.195

0.19^

0.196

Btu"-"" hr

ft °F

3.75

3.77

3.76

Same as above Alfol Type 2B

inset stapled

TT-OlU-71

TT-015-7

0.0.50

0.125

0.126

6.58

6.I19

Same as above Premium Brand

3 in. Paper

Enclosed Rock

Wool Bldg. Insul.

TT-O 30-72

TT-031-72

0.0.250.091

0.093

9.62

9.^3

Same as above 3 1/2 in. Fiberglas

Friction Fit Bldg

Insul. polyethylene

vapor barrier

TT-002-71

TT-022-71

TT-023-71

0.0.0.50

0.076

0.078

0.080

11.76

ll.i+9

11.11

Same as above 3 1/2 in. Fiberglas

Kraft Faced Bldg.

Insul

.

TT-038-72

TT-039-72

0.0,25

0.07^

0.076

12.05

11.90

Same as above 3 1/2 in. Fiberglas

Kraft Faced Bldg.

Insul. Gypsum Board

mounted on DG-8

resilient channel

TT-Oi+2-72

TT-Ol+3-72

0.0.25

0.073

0.07*+ 12.6612.20

Redwood siding

over 3/h in.

Styrofoam TG

sheathing

None TT-036-72

TT-037-72

0.0.25

0.12k

0.131

6.62

6.25

Four-inch brick

veneer over 1/2

in. wood fiber

sheathing

None TT-065-72

TT-066-72

0.0.25

0.153

0.160

5.10

h.Q8

Same 3 1/2 in. Fiberglas

Friction Fit Bldg.

Insul. , polyethylene

vapor barrier

TT-O69-72

TT-070-72

0.0.25

0.075

0.085

11.90

10.53

* Effective thermal transmittance and resistance are the values calculated from measiared

heat flow. In pressure tests , this value includes energy consumed in heating the leakage air from cold side to warm side temperature. See Table D-1 for complete data including air leakage.

77
The wood siding wall ^itfe Tiberglas 3-1/2 in. Rll Friction Fit Building Insulation

was tested at three mean temperatures; the results are plotted in Figure 6k. In the

absence of an imposed air pressure differential across the wall, the thermal resistance

which IS controlled by the resistance of the cavity insulation, decreases smoothly with

increasing temperatiire as would be ejq^ected. With an air pressure differential of O.5 in.

water, the thermal resistance dropped much faster with temperature. Inspection of the detailed data in Table D-1 , Appendix D, reveals that this decrease in thermal resistance

' IS primarily due to increased air leaicage at higher mean temperatures , probably due to waiping of the wall.

Figure 65 shows an infrared thermograph of the inside surface of a wood siding wall

with cavity insulation. In these thermographs, light areas are warmer than dark areas. The comparator plates described at the- end of Section k.2 can be seen in the lower center

of the figure. The superimposed graph of temperature corresponds to the scan position

indicated by the white bar across the entire lower portion of the figure. The irregular

dark yertical bars correspond to cold regions caused by heat flow through the studs.

b . Doors

The results of the tests on three doors and on a door plus storm door are given in

Table 2. .In all cases, the wall in which the door was installed was a 2 x U in. stud wall

with 1/2 in. gypsum board on the interior surface, 10 in. wide redwood lap siding over 1/2

in. thick wood fiber sheathing on the exterior surface, and Fiberglas 3-1/2 in. Friction

Fit Building Insulation and polyethylene vapor barrier in the cavity.

The next-to-last coliimn in Table 2 gives the effective thermal transmittance of the

wall/door combination — i.e., computed from the total heat flow, including that associated

with air leakage. The last column gives the effective thermal transmittance of the door,

computed using equation (l2) rearranged as follows

_ US - U S U = w w , (15) r SP where S and U correspond to the combination wall plus door, SWWand U correspond to the

basic wall construction and S and U correspond to the penetration (door) above. The

' * P P thermal transmittance of the basic wall construction was ass\iraed to be O.OTT Btu/(hr sq ft

°F) at 0.0 in. water (average of Tests TT-002-71 and TT-022-71) and 0.079 Btu/(hr sq ft

°F) at 0.25 in. water (interpolation between Test TT-023-71 and TT-022-71). The area of

each door was taken as 20.0 sq ft (this corresponds to the door only, not the door plus

frame )

.

. Looking at the effective thermal transmittance (i.e., including effects of air

leakage) of the doors only, it is seen that in the absence of an imposed air pressurd

difference, the addition of a storm door to a solid wood flush door decreases the thermal

transmittance by about thirty percent . The doors with urethane foam cores have about

one-half the thermal transmittance of the solid wood door. With an air pressure

differential of 0.25 in. water, the FRP door with a foam core was much better than the

other doors , in large part due to the smaller air leakage

.

c . Windows

The results of the tests on windows are given in Table 3- The wall in which the

windows were installed was of the same construction as that in which the doors were

installed. The thermal transmittance of the windows was computed using equation (15) and

the same values for the thermal transmittance of the basic wall construction as were used

in the calciilations for doors. The sash area of the windows was used in computing their

effective thermal resistance — 12.7 sq ft for the nominal 3 x 5 ft windows and 25.6 sq ft

for the nominal 6 x 5 ft windows

.

There were no large differences between the performance of locked and unlocked

windows. In the absence of an imposed air pressure difference, the addition of a storm

sash or the use of insulating glass offered about the same improvement over conventional

single glazing. The imposed air pressure drastically increased the effective thermal

transmittance of the opehable windows

.

- 78
12

t 10

JC'

'3CO

UJo

<

I00

UJ

LUI

8 -

0.0 in. water \\

\\

\

\\

0.5 in. water

I I 20 40 60 80

MEAN TEMPERATURE, °F

100

Figure 6k. Thermal resistance vs mean temperature data for a 2 x U in. stud wall with 1/2 in.

gypsum "board on the interior surface, redwood lap siding over 1/2 in. wood fiber

sheathing on the exterior surface, and 3 1/2 in. Fiberglas Friction Fit Building

Insulation plus a polyethylene vapor harrier in the cavity.

79

Table 2. Thermal transmittance of doors and -wall/door combinations. The wall was a 2 x U in.

stud wall with 1/2 in. gypsum^ board on the interior surface, redwopd siding over 1/2

in. wood fiber sheathing on the exterior surface, and Fiberglas 3 1/2 in. Friction

Fit Building Insulation and polyethylene vapor barrier in the cavity. The doors were not sealed. All doors were 1 3/^+ in. thick, 3 ft wide, and 6 ft, 8 in.

high. The nominal mean temperature was 27-5 F.

Effective*

( Thermal Transmittance

air-to-air)

Description of Door Test Wo.

Pressiire

Differential

Wall/Door

Combination Door Only

in. water Btu hr ft

^ Btu hr"""" ft'^ °F~^

Solid wood flush door,

brass weatherstrip

TT-OU9-72

TT-050-72

0.0.25

0.117

0.279

01 33

33

Same as above plus

aluminum storm door

TT-055-72

TT-056-72

0.0.250.100

0.236

01 22

06

Steel flush door with

urethane foam core, magnetic gasket

TT-059-72

TT-060-72

0.0.25

0.092

0.202

0

0 17

.85

Fiberglas Reinforced

Plastic panel door with

Torethane foam core, plastic extended

weatherstrip

TT-063-72

TT-06U-72

0.0.25

0.093

0.138

18

U5

•Effective thermal transmittance is the value calcixlated from measixred heat flow. In pressure

tests, this value includes energy consiimed in heating the leakage air from cold side to warm side temperature. See Table D-1 for con5)lete data including air leakage.

Note: Care should be taken in using these experimentally-determined values for design purposes since the film coefficients were significantly different than for most tabulated

design data.

81
Table 3. Thermal transmittance of windows and wall/window combinations. The wall was a

2 X U in. stud wall with 1/2 in. gypsum board on the interior surface, redwood

siding over 1/2 in. wood fiber sheathing on the exterior sixrface, and Fiberglas

3 1/2 in. Friction Fit Building Insulation and polyethylene vapor barrier in the

cavity. The windows were not sealed. The nominal mean temperature was 27.5 °F.

Effective* Thermal Transmittance

( air-to-air)

Window Description Test No. Pressure

Differential

Wall /Window

Combination Window Only

in. water

-1 -P -1

Rtni hr ft °V Rtii hy °V

3 X 5 ft wood double- TT-020-T1 0. 0.133 0.6h

hung single glazed TT-021-T1 0.25 0 2Q3 2.22

window, locked

Same as above, but TT-02i+-Tl 0. 0 . 136 0 . 67

unlocked TT-025-T1 0.25 0 . 3U0 2. 69

Same window as above. TT-026-T2 0. 0.110 O.hl

locked, plus single TT-02T-T2 0.25 0.3^3 2.72

glazed wood Storm

window

Same as above , but TT- 028-72 0. O.llU 0 .Us unlocked TT-029-72 0.25 O.UOl 3. 30

3 X 5 ft wood double- TT-032-72 0. 0.116

hung window, glazed TT-033-72 0.25 0.U05

7/l6 in. insulating

glass, locked

Same as above, but TT-034-72 0. 0 . 117 0.1+8 unlocked TT-035-72 0.25 0.501 i|.30

6 X 5 ft wood pi ctlore TT-OUO-72 0. 0.183 0.61

window, single glazed. TT-OU6-72 0.25 0.198 0.67

divided light

6 X 5 ft wood picture TT-OUU-72 0. . 0.135 0.37

window, glazed 1 in. TT-Ol+5-72 0.25 0.165 0.51

insulating glass, single

light

Effective thermal transmittance is the value calculated from measured heat flow. In pressure tests, this value includes energy consumed in hearing the leakage air from

cold side to warm side temperature. See Table D-1 for complete data including air

leakage

.

Note

:

Care shoiild be taken in using these experimentally-determined values for design purposes since the film coefficients were significantly different than for most tabulated design data.

82
Figure 66 shows an infrared thermograph of the inside surface of a wood siding wall

penetrated by a single-glazed 3 x 5 ft double-hung window.

4, 5. Comparison of Results with Those of Other Investigations

Rather than attempt to compare the above data with literature data, as was done in the

case of sound transmission loss, selected data will be compared with values calculated

using the tables and procedures in the 19T2 ASHRAE Handbook of Fundamentals [85]. These

design heat transfer coefficients and procedures represent a consensus of many experts and

thus implicitly include carefully evaluated experimental data, both published and

unpublished. For the walls without penetrations, the comparison will be done on the basis

of surface-to-surface thermal resistance. For doors and windows, the comparison will be

done on the basid of air-to-air thermal transmittance with an adjustment for stirface film

coefficients.

4. 5. 1. WaUs

The ASHRAE calculation procedure involves adding up the series thermal resistances

along two parallel heat flow paths (through the studs and through the cavity) and then

combining these parallel resistances using equation (13).

For the uninsulated atud wall, this calc\ilation proceeds as follows:

Path through Stud Path through Cavity

Material

Thermal

Resistance Material

Thermal

Resistance

1/2 in. gypsum board

2 X U in. stud

1/2 in. sheathing

5/8 in. wood siding

Btu""^ hr ft^ °F

U.35

1.32

0.93

1/2 in. gypsum board

31/2 in. air space

1/2 in. sheathing

5/8 in. wood siding

Btu"-^ hr ft^ °F

1.0 ( approx .

)

1.32

0.93

Total T.05 Total 3.7

Assuming the studs occupy 10 percent of the total wall area, equation (13) yields

Jl. ^b. t + ^ - = 0^ ^ 0.90

^

S 'r^ S 'r^ T.05 3.7

so that R = 3.9 hr sq ft °F/Btu. The average measured value (see Table l) was 3.TT hr sq ft

°F/Btu The agreement is better than might have been expected since the values for the

resistance of the air space [85,^9] are not well known for temperature differences as large

as were used in the present investigation.

In order to predict the thermal resistance when the cavity is filled with "R-11

insulation", the thermal resistance of the air space is replaced with a value of 11.0 hr sq

ft °F/Btu and the above calculation repeated, yielding an overall thermal resistance of 12.5

hr sq ft °F/Btu which is in good agreement with the range of values {ll.h6 - 11.9^ hr sq ft

°F/Btu) measured for 3-1/2 in. Fiberglas insulation in the absence of an imposed air

83
pressure difference. (Still "better agreement was obtained when measured values

[116,117] were used for the thermal resistance of the cavity insulation.)

'4. 5. 2. Doors

Table 9 in Chapter 20 of the ASHRAE Handbook of Fundamentals [85] tabulates overall

air-to-air thermal transmittances for several kinds of doors. These design values

correspond to "still air" inside but a 15 mph wind outside while the experimental values in

the present investigation had slowly moving air on both sides. Accordingly, for

lit/ comparison, the data from Table 2 have been adjusted— to correspond to the ASHRAE

conditions. Table h shows the comparison. It is seen that the agreement is quite good for

a wooden door, with and without a storm door. The steel door with a urethane foam core in

the present investigation is seen to be much better than the ASHRAE design value.

4. 5. 3. Windows

Table 8 in Chapter 20 of [85] tabulates overall air-to-air thermal transmittances for

several kinds of windows. These values are compared with adjusted (see Section I+.5.2)

values from the present investigation in Table 5- The agreement is seen to be quite good.

— By using equation (lO) , subtracting a film resistance corresponding to a stillair film coefficient of l.h6 Btu/(hr sq ft °F) and adding a film resistance . corresponding to a surface film coefficient of 6.00 Btu/(hr sq ft °F).

81+
Table k. Comparison of ASHRAE design values [85] for thermal transmittances

of doors with the results of the present investigation (without an imposed air pressure difference').

Effective Thermal Transmittance

ASHEAE Present Investigation

[85] [adjusted from Table 2]

Btu hr"""" ft"^ "F"-^ Btu hr"""" ft~^ "F""""

Solid wood, 1 3/^ in. O.i+6 ^ O.ko ^

Solid wood, 1 3/h in. 0.31

^ 0.25

^ plus metal storm door

Steel, 1 3/h in. with o.ko 0.19

^ urethane foam core

Interpolated

Adjusted (see text) to an outdoor surface film coefficient of 6.00

Btu hr"-"" ft"^ "F"""-.

85
Tatle 5- Comparison of ASHRAE design values [85] for thermal transmittance

of windows with res\ilts of present investigation (for -locked ^windows

without an imposed air pressixre difference). The designation "Q0%

glass" or "100^ glass" corresponds to ASHRAE adjustments based on portion of sash area which is glazed.

Effective Thermal Transmittance

Description of Window

ASHRAE

[89]

Present Investigation

[adjusted from Tahle 3]

Btu hr ft~^ °F

-1 -? —1

rstu nr 11; r

Single glazing, Q0% glass 1

1 0202

0.96 ^'^

0.89

^'^

T/16 in. insulating glazing,

80% glass 0 66 0.62

^

1 in. insulating glazing,

100^ glass 0 56 0.1+6^

Single glazing plus wood storm

window, 80^ glass 0 50 0.52^

Adjusted (see text) to an outdoor siirface film coefficient of 6.00

Btu hr""^ ft~^

3 X 5 ft douhr e-himg window

6 X 5 ft picture window

86
5. Air Leakage Tests

5. 1. Background

Air leakage into (infiltration) and out of ( exfiltration) biiildings is of concern because it increases the cost of vinter heating and summer cooling, creates drafts, and

makes difficult the maintainance of a controlled relative humidity. Condensation within

vails and between panes of double windows, resulting from exfiltration during cold weather,

can damage the building. Air leakage also determines the entrance and exit of smoke and

odors and is important with respect to rain leakage and dust penetration. The soiznd insulation provided by exterior walls is greatly influenced by the existence of- paths large

enough to allow significant air leakage.

Chapter 19 of the ASHRAE Handbook of Fundamentals [85] discusses air infiltration and

gives numerous references to the literature. Other references of interest include [103,

I20-I2I+].

Air infiltration and exfiltration result from air pressure differences between the

inside and outside of a building. Such pressure differences result from air flow around and

over buildings and from air density differences caused by temperature differences between

the inside and outside air. For air at standard density, the stagnation pressure is related

to wind speed by

p^ = O.OOOU82 v^, (16)

where v is the wind velocity and p is the stagnation pressure, or velocity head (in.

water). Values of the stagnation pressure for winds from 5 to 25 mph are given below:

Wind Speed Stagnation Pressure

mph in. water

5 0.012

10 O.OkQ

15 O.IOI+ 20 0.193

25 0.301

According to [85], pressure may vary from +0.5 P^ to +0.9 P^ on the windward side and from

-0-3 p^ to -0.6 p^ on the leeward side for simple square or rectangular buildings, depending

on the angle of the wind. Pressures on the other sides, parallel to, or at slight angles to the wind direction, may range from -0.1 p^ to -0.9 P^-

The "stack effect", or air flow due to indoor-to-outdoor temperature differences, can be very important in tall buildings but, compared to wind effects, is of little consequence

for air flow through walls and windows in residences which are only a few stories high.

The air leakage due to a given pressure difference may be expressed as

V = C(Ap)'', (IT)

where V is the volumetric flow rate (e.g., cfm) , C is a proportionality constant, Ap is the

indoor-to-outdoor pressure difference and n is an exponent between 1/2 and 1. In the United

States and Canada, air leakage characteristics of windows are usually expressed as flow rate

per foot of sash crack.

87
5. 2. Experimental Procedure

ASTM E283-73, Standard Method of Test for Rate of Air Leakage Through Exterior

Windows, Curtain Walls, and Doors [125], covers the determination of the resistance of

exterior windows, curtain walls, and doors to air infiltration resulting from air pressure

differences. This test is applicable to any curtain wall area, or to windows or doors

alone, and consists of sealing a test specimen into or against one face of an air chamber,

supplying air to or exhausting air from the chamber at the rate required to maintain the

specified test pressure difference across the apecimen, and measuring the resultant air

flow through the specimen.

The following describes the procedure used in carrying out air leakage tests in the

sound transmission facility. An essentially similar setup was used in the thermal test

facility.

The facility for air infiltration measurement is patterned after ASTM E-283. The

pressurized airtight chamber specified in the Method consisted of the entire source room

used normally for sound transmission tests as described in Section 3.2. This room is

normally well sealed for sound leakage and was made more airtight by caulking and taping

all openings and installing new gasketing on the double doors

.

Air was fed into the test chamber as illustrated in Figure 67- A Dayton 2-C- 820, 9 in. wheel blower, with a rated delivery at 3^50 rpm of l60 cfm at 5 in. water static

pressure, driven by a Dayton 6-K-011.1/2 HP variable speed motor with speed continuously

variable from 500 to- 5000 rpm was used. Air flow into the room was measured by a •calibrated orifice plate and a pair of flanges with pressure taps, manufactured by Foxboro

Company. The pressure difference across the orifice plate was measured by a Dwyer Model

U2U-IO inclined manometer, having a slant range of 0-2 in. water gauge in a scale length of

20 in., plus a vertical range of 2.1 to 10 in. The air flow metering section was based on

•standard 3 in. pipe (3-068 in. ID) and was designed strictly as specified in [126].

The air was delivered to the room through a 3 in. elbow which was imbedded in the

concrete wall during building construction. This elbow was connected to the metering

section by the intermediate pipe connections and duct work. The interior side of the elbow

was fitted with a threaded plug which could be used to test for any leakage between the

metering section and the room. For air delivery, the plug was removed.

Static pressure in the room was measured with a Dwyer Model 200.5 slant manometer

having a range of 0-1 in. and a scale length of 8 in. The manometer was connected to the room interior through a small pipe opening previously existing in the concrete wall. This

opening was about 30 in. away from the air delivery point.

In conducting a test, the fan speed was set to pressurize the room over a range of 0.1

to O.T in. water above atmospheric pressure in steps of approximately 0.1 in. water.

Points of air flow in cfm versus pressure were plotted and a smooth curve drawn through the

points. The intersections of this curve with the exact pressure points of 0.1, 0.3 and 0.7

in. water were then tabulated and presented as the final data.

In the course of the program, three different wall constructions surrounded the test

specimen; namely, the gypsum board filler wall used for the early tests and later two

separate constructions of the wood siding exterior wall. In all cases, the walls were

thoroughly sealed with two coats of shellac or paint. When windows of various sizes were

tested in a given wall, an opening was cut for the largest, and the excess area for the

smaller units was filled in^with gypsum board which was shellacked. Care was taken to seal

the joints at all svirface discontinuities as thoroughly as possible. Measurements of

residual leakage for the entire room, over the pressure range from 0.1 to 0.7 in. water for

the three unbroken walls showed the following:

88
SEALED WOOD SIDING WALL

126 ft2 WINDOW SPECIMEN

PRESSURIZED ROOM

4400 ft3

GASKETED" DOORS

FLOW METER

VARIABLE AIR SUPPLY

T

PRESSURE

MEASUREMENT

gure 67. Experimental setup for measiaring air filtration of doors and windows in the

soiind transmission facility.

89
Wall Air Flow

„,3 •. -1

ft mm

6.1 in water 0.3 in. water O.T in. water

Gypsum board, s shellacked and

painted t 2 k U.T T.9

Wood siding wall No. 1, painted 2 h 5.1 9.0

Wood siding wall No. 2, painted 2 1 3.1+ 5.3

For each test of a window, interpolated values of residual leakage were subtracted from the

overall measured air flow, it being assumed that the residual leakage was not changed by

the use of gypsum board filler areas or by any of the resulting joints.

5. 3. Calculation Procedures and Uncertainties

Air flow rates were determined from the calibration of the orifice plate (see below);

presstire differences across the orifice plate and between the source and receive rooms were

read directly from the manometers. Thus ho special calculation procedures were required.

The Foxboro orifice plate was 'supplied with a calculated calibration point of 50 cfm

at standard conditions'^'' at a pressure drop of 2.0 in. water. A calibration curve was drawn from this point with a logarithmic slope (cfm versus in. water) of 0.5. This ciirve was then compared with readings of a Meriam Laminar Flow Element, Model 50MW20, which was placed upstream of the orifice plate, having a nominal range of 20 cfm at standard

conditions. These readings agreed with the Foxboro calibration curve within plus or minus

2 percent between 7 and 20 cfm. Below this range, the logarithmic slope of the orifice

curve became nonlinear, and the Meriam readings were used to extend the calibration curve

down to 2 cfm. Above 20 cfm, the calibration curve of the orifice plate was used as supplied. The accuracy of the overall calibration curve of cfm at standard conditions

versus pressure drop across the orifice plate was taken as plus or minus 2 percent.

The laboratory environment during the test program was maintained at 7^+ 1.2 °F and 50

+_5 percent relative humidity. At standard barometric pressure (29-92 in. Hg) , these

conditions, if not corrected to standard conditions, correspond to an error of -0.7 percent

in air flow measiirement . Extremes of barometric pressure from 29-0 to 31.0 in. Hg

superimposed on the above change wo\ild cause a total error of from -2.2 to +1.2 percent.

In view of considerably larger uncertainties in the test measurements, no corrections were

made in the actual tests from room air to standard air.

Inaccuracies in the test procedure arose from several causes and were observed chiefly

at low flow rates and low pressure drops across the specimen. Contributing causes were:

(1) Fluctuation of pressure differenae across the specimen due to gusts of wind outdoors,

causing poor readability of both air flow and room pressure.

(2) Uncertainties in the, exact value of residual air flow. At low overall flows not much

. larger than the net flow being measured, the net flow would be subject to considerable

error due to an unknown change in the residual leakage.

As a rough estimate, the accuracy of the method can be placed at about 0.5 cfm, or 5 percent, whichever is larger. In view of wide variability of test specimens themselves,

this accuracy appeared acceptable for the purposes of the program. — Denotes dry air at standard conditions: pressure — 29.92 in. Hg. ; Temperature — 69. h °F; Density ~ 0.075 lb/cubic ft.

90
5. 4. Results

16/ Separate tests for air infiltration— were run in the sound transmission and thennal

transmission facilities, respectively. For the former, one of the two rooms comprising the

facility was pressurized over a range of 0.1 to O.T in. water, and air flow measured at normal room temperatures, 75 °F. These tests were run only on the doors and windows.

Early air infiltration tests in the thermal transmission facility were run at a pressure of 0.5 in. water. They were run at the same hot and cold side temperatures used

for heat transmission measurements, 75 °F and -20 °F, except for two tests at higher mean

temperatures. Air pressure was lowered to 0.25 in. water when it was discovered that some

of the window units required greater volumes of dry air than the equipment could supply.

Infiltration tests were run both on unbroken walls and on combinations of a wall with door

or window. The doors and windows were normally moiinted without special sealing.

Air infiltration data measured in the sovind transmission facility are given in

Appendix E in the form of tables of air flow versus pressure drop. The air flows at 0.1,

0.3, and 0.7 in. water pressiire are listed in Table E-1 for doors and Tables E-2 and E-3

for windows

.

Air infiltrations measured in conjimction with thermal transmission at pressures of

0.25 and 0.5 in. water are listed with the thermal data for each test construction in

Appendix D.

5. 4. 1. Summary and Conclusions

The following observations relate to data taken in the sound transmission facility:

a. Air flow measured through accurately gauged cracks around a window was found to be

closely proportional to crack width and length and to a power of the room pressure

ranging from 0.5^ to 0.72.

In the following, the single-number ratings for air infiltration through doors and windows

tested in the sound transmission facility are given as net air flow in cfm for a room pressure of 0.3 in. water on the exterior side.

b. A 3 X 7 ft wood door unit with spring brass weather strip supplied with the frame, and

half-round plastic threshold strip, showed an average of 10 cfm. This was the lowest

value obtained for a normally fitting door. A lower value was obtained for a slightly

oversize door which made a forcing fit with the frame.

c. A steel- faced door with magnetic weather strip supplied with the frame and three soft

plastic threshold wiping strips, tfested at 15.^ cfm.

d. Addition of an aluminum storm. door with minimal weather stripping lowered the air flow

by only about 2.5 cfm.

e. All of the operable windows, including the sliding glass door but not the jalousie

window, covered a range of approximately 5 to 25 cfm locked and 5 to 70 cfm unlocked.

The jalousie window tested at 83 cfm.

f . Addition of storm sash made only a negligible reduction in air flow for the windows

tested.

g. In some cases, locking the window increased the air flow, due to twisting or displacement of the sash. — Measurements were made only with air flow in the direction corresponding to infiltration as opposed to exfiltration (see [l2i|,125j).

91
5. 4. 2. Discussion

a. Doors

All of the air infiltration tests on doors were made with the doors normally closed.

The tests involved three types of weather strip and two threshold seals . The data for

pressure differences of 0.1, 0.3, and 0.7 in. water are given in Tahle E-1 in Appendix E.

For three wood doors in the same frame and against the same spring brass weather strip

and half-round plastic threshold seal, the air flow at 0.3 in. water ranged from 8.9 to

11. k cfm. This amounted to a test for repeatability of interchanged doors and normal

closings

.

Replacing the brass weather strip with the extruded plastic strip in the same frame

and with the same wood door raised the air flow to 19-8 cfm. The plastic strip, however,

could not be installed exactly in accordance with its design, and this may account for the

higher air flow. On the other hand, replacing the wood door with an FRP panel door in the

same frame and against the plastic weather strip lowered the air flow to h.O cfm. As noted

in Table E-1, the FRP door was somewhat oversize and made a very tight fit against the

weather strip.

The steel door in its own frame with magnetic weather strip and soft plastic fingers

closing the threshold showed somewhat higher air flow (15.^ cfm) than the wood door in its own frame with brass weather strip and half-round threshold seal.

The addition of the aluminum storm door to the wood door with plastic weather strip

lowered the air flow only from I9.8 to 17-2 cfm. The storm door had only minimal weather

stripping, consisting of a thin plastic strip on three sides and a single soft plastic

finger at the threshold.

b . Windows

Airflow tests were run on the same set of perimeter cracks around the pict\ire window

on which sound transmission was measured. The results are plotted in Fig\ire68, showing

airflow in cfm per foot length of crack as a function of room pressure for each crack width

and length. The data were corrected for residual flow. For each crack width, the airflow

was very closely proportional to a power of the pressure which ranged from approximately

0.72 for a 1/32 in. crack to 0.5^ for the 1/8 in. and 1/k in. cracks. Where data corres- ponding to two crack lengths are shown for the same crack width, there is good agreement

between the corresponding airflows per unit length.

The same data are shown in Figure 69 for a constant room pressure of 0.3 in. water,

as a function of crack width. The airflow was roughly proportional to crack width over the

range measured, the deviation from strict proportionality being indicated by the departures

from the straight line drawn through the data points. Taking the straight line as an average, and assuming an average logarithmic slope of airflow versus pressure of O.56, the

following empirical equation may be used as an approximation to the data;

(ft^ min"""") per foot length of crack = 281; w

p°'^^

where: W = crack width, in.

p = room press-ure, in. water

As shown in Table E-2, the air flow at 0.3 in. water pressure for all of the windows

tested, as normally closed and/ or locked, covered a very large range — from 1.8 cfm for

the fixed casement window to 82.6 cfm for the jalousie window. Since the latter had no provision in its design for air sealing, it should probably be considered only as an extreme end point in the test series. Omitting this window, the highest airflow for locked

or latched windows was approximately 25 cfm for the wood double hung window locked and 70

cfm for the same window unlocked. This was a typical low-cost window purchased at the

local lumberyard.

92
50

a10

1

I I I I I I I

1 1

k = LOGARITHMIC SLOPE OF BEST FIT LINES.

CRACK

WIDTH

1 TT

0.03

1/4 In

1/16 In

1/32 in

J I L _L J I L

0.1 1.0 PRESSURE, INCHES WATER

Figure 68. Air infiltration through gauged cracks around picture window. Multiple points

at the same pressure and crack width represent crack lengths varying from 2 to 20 ft.

50

10

1 I I I I I I

\ y

A

I I I I I 0.05 0.1 CRACK WIDTH, INCHES

0.5

Figure 69. Air infiltration, as a function of crack width, through gauged cracks around

picture window at 0.3 in. water pressxire.

93
The wood-plastic windows were much better, showing 5 to 6 cfm both locked and

imlocked. The awning and operable casement windows of the wood-plastic type ranged up to 10 cfm for the locked or tightly closed condition, and the sliding glass door measured l6

and IT cfm, locked and imlocked, respectively.

The al-uminum windows covered a wide jrange from 5-6 cfm for the single hung window,

locked, to kh.S for the operable casement window,, unlocked. Although not enough samples were tested to make generalizations, it appeared that as- a group the aluminum windows were

roughly between the plain wood and the plastic-wood windows.

In some cases, the unlocked windows showed slightly lower air flow than the same windows locked. This was apparently due to the fact that the locking tended to twist or displace the sashes enough to cause a larger leak around each sash perimeter.

For awning and casement windows, which open outward on hinges, it was noted that*' increasing room pressure on the exterior side sometimes tended to close the windows more

tightly. This is shown clearly in Table E-2 in Appendix E.

Table E-3 in Appendix E shows data obtained on the effect of opening an awning window

by gauged amounts. The opening was gauged by inserting shims at the bottom of each sash.

The data were not reproducible, however, since a repeat with different sashes in the same frame showed much less change in air flow for the same openings.

In general, all of the air infiltration data, because of, the limited and more or less

random sampling of windows, should be considered as illustrative rather than definitive.

Direct comparisons of air flows measured in the sound transmission facility at room

temperat\ire with those measured in the thermal facility were made for one window and three

doors. The results, with the sound-transmission-facility data corrected to a common basis

of 0.25 in. water pressure, are as follows:

Test No. Unit Tested

Thermal

Facility

Two-Room

. Facility

^,3 . -1

ft mm ft mm

TT-033-T2 Wood double-hung window, glazed

insxilating glass , locked ho 22

TT- 035-72 Same, unlocked 50 62

TT- 05 0-72 Solid core wood door, brass

weather strip 22 9

TT-060-72 Steel door, urethane foam core, magnetic weather strip 15 ih

TT-06i+-72 FRP panel door , urethane foam core plastic weather strip 7. 3

There is only very rough agreement, the values for the thermal facility being

generally higher. The best agreement appears for the steel door. It should be noted that

close agreement should not necessarily be expected. The 95 °F temperature differential for

the thermal tests should be expected to cause dimensional distortions which could greatly

alter perimeter leakage characteristics [122].

9h
5. 5. Comparison of Results with Those of Other Investigations

Because of the large variation an leakage rates among windows, depending upon design,

fahri cation and installation, there is little point in a detailed comparison of the present

data with that of previous investigations

.

The ASHRA.E Handhook of Fundamentals [85] gives the design values, for double- hung

wood windows, shown in Figure TO. The ranges of values shown correspond to "average fit"

to "loose fit". ASHRAE also gives rough equivalences between other types of windows and

the wood double-himg windows. Figure TO also shows, for comparison, data from the present

investigation for locked wood and wood-plastic double-hung windows as measured in the sound

transmission facility. The reader interested in more detailed comparisons should consult

[12O-I2U] and the references therein and in [85]. In addition, comparisons can be made

with industry specifications put out by the Architectural Aluminiun Manufacturers Association,

the National Woodwork Manufacturers Association, and the Mobile Homes Manufact\jrers Association.

95
0.1 0.2 0.3 0.4 0.5

PRESSURE DIFFERENCE, in. water

Figiare 70. Air infiltration, per foot of crack, for locked wood (Test W-2U-T1) and voodplastic (Test W-T^-7l) double-hiang windows compared with ASHRAE design values.

96
6. Correlations among Sound Transmission Loss, Thermal Transmittance,

and Air Leakage Test Results

6. 1. Sound Transmission Loss and Air Leakage

Section 3.5.^ includes a "brief discussion of sound transmission through cracks of

known geometry. In general, however, cracks around doors and windows and leaks in walls

will be of unknown geometry and some means is needed to estimate the effective size of the

cracks. This need was a prime motivating factor in conducting the air leakage tests in the

sound transmission loss facility.

The following rather simplistic approach was found to lead to an adequate correlation

between sound transmission loss data and air leakage data.

Assimiption 1 Design calculations on the effects of cracks and openings on the

effective sound transmission loss can be based on a single-figure rating, e.g. , Sound

Transmission Hlass, and detailed effects at different frequencies can be ignored.

From equation {h) , one can write

Tg^Sg = T*S - t'^»S, (IB)

where x* is the effective sound transmission coefficient of the leaky window of area S, x^*

is the effective transmission coefficient of the sealed window, also of area S, and Xg* is

the effective transmission coefficient of the crack of area S . The asterisk on each x indicates that the transmission coefficient is that corresponding to the sound transmission

class, i.e., STC = 10 log (l/x*).

Taking logarithms,

STCg - 10 log S^/S^ = -10 log

-STC/10

10 - 10

-STC^/10

-10 log S/S [19)

where the reference area is S^ = 1 ft and where STC, STC^, and STC^ are the Sound

Transmission Classes of the leaky window, the sealed window, and the leak, respectively.

Since S^, the leak area, is not known, one cannot compute STC but one can obtain, using

equation (l9) the quantity (STC^ - 10 log S^/S^).

. Assiunption 2 The Sound Transmission Class of an opening is approximately

independent of the size of the opening; thus the sound power (in an "STC-sense")

transmitted through an opening is proportional to the area of the opening.

Assumption 3 Typical leaks are sufficiently alike (e.g., in terms of depth) that, at a given pressure difference, the air leakage rate is proportional to the area of the

opening.

Assumptions 2 and 3 lead to

T^S^ = KV, (20)-

where V is the air leakage rate at some particular pressure difference and K is a constant

relating the leakage rate to the (unknown) crack size. Again taking logarithms

STCg - 10 log S^/S^ = -10 log K - 10 log V/V^ , (21)

where V = 1 cfm.

o

97
Figure 71 shows the quantity (STC^ - 10 log S^)^ as computed from equation (19)^

plotted vs -10 log V/V , where V is the air leakage rate (cfm) at a pressure difference of

0.3 in. water. The da?a points plotted include all tests on doors or windows without storm

sashes where the effect of the leak was sufficiently severe as to lower the Sound

17/ Transmission Class— by at least 3 (it was felt that the experimental precision did not allow reliable determinations of STC2 - 10 log Sg for smaller differences). As .will be

seen below, some of the data with a storm window or door in place did not lie close to the

line in Figure 71 so no data corresponding to storm windows or doors were included. (These

data are shown in Figure 72, below.) The solid data points represent "normal" leaks which

occurred for closed (locked or unlocked) windows. The open data points correspond to the

artificial cracks around the 6 x 5 ft picture window and the 3 x U ft wood-plastic awning

window

.

The solid line in Figure 71, which was fitted to the solid data points, corresponds

to (cf. equation (?!))

STC^ - 10 log S^/S^ = 26.U - 10 log V/V^. (22)

The dashed lines are 3 dB above and below the solid line. Substituting equation (22 ) into

(19 ) and rearranging.

STC^ - STC = 10 log

where, as before, V is expressed in cfm at 0.3 in. water and S in sq ft.

Figure 72 shows the predicted change in Sound Transmission Class, as computed from

equation (23 ) plotted vs the actual observed change. The agreement for experimental

changes greater than 3 is to be expected, of course, at least in the absence of storm

windows or doors, since these are the same data as were used in deriving equations (22) and

(23). As stated previously, experimental values less than about 3 are subject to

considerable uncertainty. Ignoring these small values, which are of little practical

concern anyway, almost all of the experimental data lie within + 3 of the prediction. The

most notable departure from agreement corresponds to the solid core wood door plus aluminiom

storm door (Tests W-UO-72 (unsealed) and W-Ul-72 (sealed)) where the experimental value was about 7 less than that predicted '(i.e., the prediction erred on the conservative side).

The data in Figure 72 indicate that equation (23) may be used with some confidence in

predicting the effect of cracks on the Sound Transmission Class of doors and windows from a simple measure of the air leakage rate. A family of curves, generated using equation (23),

is shown in Figure 73. These curves clearly show the large influence of air leakage on elements which otherwise have a high sound transmission loss.

2 As an example of the use of Figure 73, consider a window of area 15 ft having an inherent (i.e., when sealed) Sound Transmission Class of 30. If the measured air leakage

rate was 30 cfm at 0.3 in. water, V/S would be 2.0 ft/min. Entering Figure 73, this is seen to correspond to a decrease of 7-5 in STC so the predicted value would be 22.5 (or,

rounded down, 22).

Seifert [127] has published a nomogram for estimating the effect of air leakage of

the sound transmission loss ~of windows. Since his procedure is based on a pressure

difference of 1 mm water (lower than was examined in the present investigation) and he is

interested in the average sound transmission loss from 100 to 3150 Hz (rather than the

Sound Transmission Class) a direct comparison is not easy to make. —^''The Sound Transmission Class was computed "exactly" rather than to the nearest

1 dS and the "-8 dB rule" was ignored in order to avoid -introducing spirrious

scatter into the data.

1 + .00229 V/S

^Q-STC^/10 (23)

98
PREDICTED (STCi-STC)

Figure 72. Experimental values for the decrease in sound transmission loss due to leaks

around windows or doors versus values predicted using equation (22). The

open symbols represent conventional calculations [22] of the Sound Transmission

Class. Closed symhols correspond to STC-values computed exactly (rather than

to the next lowest decibel) and without invoking the "-8 dB rule".

99
V/S, ft min.-i

Figtire 73. Expected decrease in Sound Transmission Class as- a function of air leakage

rate divided ty area. The air leakage rate, V, measured according to ASTM

E283-T3 [125] is- expressed in scfm at a pressure difference of 0.3 in. water.

The window or door area, S, is in sq ft. The parameter on the curves is the

Sound Transmission Class of the sealed unit (window or door)

.

100
Parenthetically, there might "be an advantage to using, as Seifert did, a much smaller

pressure difference in the air leakage tests since there would then he less • chance of the

pressure difference opening or closing cracks so as to change the effective crack size from

what woiild be present during sound transmission loss tests. However, air leakage at a pressure difference of 0.3 in. water is a commonly cited value in the United States and

Canada so it was used in the present correlation.

6. 2. Thermal Transmittance and Air Leakage

Table D-1, in Appendix D, includes values of the apparent amount of net heat flow due to air leakage, as computed from equation (1^+). It is seen that for many of the tests on walls with penetrating doors and windows, the heat flow associated with leakage is much

larger than that due to thermal conduction. Thus it is important to accurately assess the

influence of air leakage on the effective thermal transmittance.

Let U and U' designate the effective thermal transmittance of a wall (including any

penetrations) in the absence and presence, respectively, of air flow through the wall.

Then, from equations (9) and {ik) it follows that

U' - U = 1.08 |- Btu hr""'- ft"^ °F"-^, (2U)

where V/S is the volumetric flow rate (scfm) per unit area (sq ft) of wall. Figure shows

the experimentally-detennined increase in thermal transmittance, for all the pairs of tests

(with and without an imposed pressure difference) in Table D-1, plotted vs the increase

predicted by equation (2^+). Log-log paper was used so as to make the fractional error in

the prediction more evident. It is seen that the experimental values fall well below the

predicted values for very low flow rates but that the agreement becomes asymptotically

better (as regards fractional, not absolute, error) for large flow rates. It is not

apparent whether the behavior exhibited in Figure 7^ is correct or is due to experimental

error (e.g., undetected air leaks or systematic errors in air flow measurement). Bursey and

Green [122] have observed rather similar behavior in their measurements on double- glazed

windows. They attribute it to partial heating of the air as it passes through the space

between the windows but their arguments are not very convincing.

The following equation was modified empirically from equation {2k) to account for the

observed behavior in Figure 7^

:

U' - U = 0.93

^'q''^ Btu hr"^ ft"^ °F"-^. (25)

The value, 0.7 cfm, which is subtracted from V in equation 25 is consistent with a measiured

value of cold box air leakage of 0.6 cfm for the one test setup for which this measurement

was made. This leakage probably varies from test to test but is believed to have always

been less than 1 cfm. Although, as shown in Figure 75, equation (25) more' acciarately

conforms to the resvilts of the present investigation than does equation (2^) , it should not be used for predictive purposes pending a better understanding as to why the proportionality

constant (0.93) is less than would be expected (l.OB).

6. 3. Sound Transmission Loss and Thermal Transmittance

Acoustical and thermal energy transfer through walls, doors, and windows obey very

different physical principles so one should not expect very good correlation between sound

transmission loss and thermal transmittance. However, in considering alternative

constructions, it is useful to compare these two properties.

Table 6 lists Sound Transmission Class and thermal transmittance at 25 °F for those

basic walls, doors, and windows (no combinations) for which comparable data were obtained.

These same data are plotted in Figure 76. Although, as expected, there is considerable

scatter, the overall trend of the data is important to remember — good acoustical

performance (high STC) usually implies good thermal performance (low thermal transmittance).

101
.001 .002 .005 .01 .02 .05 .1 .2 .5 PREDICTED INCREASE IN U-VALUE.

Btu hr"' ft~2 °F-i Figure 7^. Experimentally observed increase in effective thermal transmittance of 9 x lU

ft vails, with and without penetrating doors or windows, vs the increase predicted "by equation (23). The scatter for small values of thermal transmittance

arises from imprecisions in both the thermal transmittance data and the air

flow rate data (used in equation (23)).

.001 .002 .005 .01 .02 .05 .1 .2 .5

PREDICTED INCREASE IN U-VALUE,

Btu hr-' fr^ °F-i Figure 75- Experimentally observed increase in effective thermal transmittance of 9 x lU

ft walls, with and without penetrating doors or windows, vs the increase pre-

. dieted by -equation (2U). The data points shown just to the left of the lefthand ordinate correspond to predicted values below the range of the abcissa

(cf. corresponding points in Figure (7^))- The dashed lines bound the region

+^20 percent around the line of perfect concordance.

102
\

0.8

£ 0.6

0.4

0.2

0.0

1

1 1

• WALLS

WINDOWS

DOORS

T

•

•

1

•••

1

• •

1 20 30 40 50 SOUND TRANSMISSION CLASS

60

Figure T6. Comparison of Sound Transmission Class and thermal transmittance for basic walls,

doors 5 and windows. The data plotted are listed in Table 6.

103
Table 6. Comparison of sound transmission loss data and thermal transmittance

data for walls, doors, and windows. The sound transmission loss tests

correspond to the sealed condition. The thermal transmittance tests

correspond to the locked condition, with no imposed air pressure

difference, at a nominal mean temperature of 27,5° F

Sound Transmission Loss Thermal Transmittance

Specimen Test No. STC Test No. U

(air

-Value

-to-air)

Walls

Btu hr ft"^ °F"^

Wood siding "wi^bh. no cavity insulation

W-I(-72 37 mm fifi-| 7-1 TT-018-71

•195

.191+

Wood siamg with j l/^: in. Fiherglas Friction

Fit Bldg. Insul.

W-7-72 37 mm r\riO TT-022-71

.076

.078

Wood siding with Alfol

Type 2B insulation

W-6-72 37 mm rM )

)

.125

Wood siding with

Premium Rock Wool

W-5-72 38 TT-030-72 .091

Wood siding with 3 1/2

in. Fiberglas Kraft

Faced Bldg. Insul.

W-5I+-7I 39 TT-038-72 .07^

Same as above but

gypsum board on resilient channel

W-55-71 hi TT-Ol+2-72 .072

Brick veneer with no cavity insulation (resilient channel for

acoustic test only)

W-l+6-71 5^ TT-065-72 .153

Brick veneer with 3 1/2

in. Fiberglas Friction

Fit Bldg. Insul.

56 TT-069-72 0 .075

Doors

Solid wood flush door W-91-71 30 TT-Ol+9-72 0 .33

Same as above plus

aluminum storm door

W-lii-71 1+2 mm ncrc: to 0 .22

Steel flush door with

urethane foam core W-3-72 28 TT-059-72 0 .17

Fiberglas Reinforced

Plastic panel door with

turethane foam core

W-l+li-72 26 TT-063-72 0 .18

101+
TalDle 6 (Con'd)

Sound Transmission Loss Thermal Transmittance

Specimen Test No. STC Test No. U-Value

Cair-to-air)

Windows

3 X 5 ft wood double

hung window single

strength glazing

W-Ul-Tl 29 TT-020-T1 0.6h

Bame as ahove plus

single glazed wood

storm window

W-3T-T1 3k TT-026-T1 O.kl

3 X 5 ft wood double

hung window, T/l6 in.

insulating glass

W-32-71 29 TT-032-T1 o.i+7

6 X 5 ft wood picture

window, single glazed

W-8-T1 28 TT-0U0-T2 0.6i

6 X 5 ft wood picture

window, 1 in. insiolating glass

W-7-71 29 TT-0i|U-T2 0.37

105
7. References

[l] Harris, C. M. (Editor), Handbook of Noise Control (McGraw-Hill, New York, 1957).

[2] Beranek, L. L. (Editor), Noise and Vibration Control (McGraw-Hill, New York, 1971).

[3] Young, R. W. , Physical properties of noise and their specification. Chapter 2 in

Harris [l].

[h] Franken, P. A., The "behavior of sound waves, Chapter 1 in Beranek [2].

[5] Beranek, L. L. , Levels, decibels, and spectra. Chapter 2 in Beranek [2].

[6] Rudnick, I., Propagation of sound in the open air. Chapter 3 in Harris [l].

[7] Kvirze, U. , and Beranek, L. L. , Sound propagation outdoors, Chapter 7 in Beranek [2].

[8] Beranek, L. L. , Sound in small spaces. Chapter 8 in Beranek [2].

[9] Embleton, T. F. W. , SoTind in large rooms. Chapter 9 in Beranek [2].

[10] Ingerslev, F. , and Harris, C. M. , Control of solid-borne noise in buildings, Chapter

19 in Harris [l ]

.

[11] Cook, R. K. , and Chrzanowski , P., Transmission of air-borne noise through walls and

floors. Chapter 20 in Harris [l].

[12] Ver, I. L. , and Holmer, C. I., Interaction of sound waves with solid structures.

Chapter 11 in Beranek [2].

[13] Sabine, H. J., Acoustical materials. Chapter I8 in Harris [l].

[ih] Beranek, L. L. , Criteria for noise and vibration in communities , buildings and

vehicles, Chapter I8 in Beranek [2].

[15] Effects of Noise on People, EPA Report No. NTID300.7 (U. S. Environmental Protection

Agency, Washington, D. C. , December, 1971). Available from U. S. Government Printing

Office, Washington, D. C. 20U02, as GPO Stock No. 5500-0050, Catalog No. EP1.2:N69/10. Also available from National Technical Information Service,

Springfield, Va. 22151, as Accession No. PB-206723.

[16] Public Health and Welfare Criteria for Noise, EPA Report No. 550/9-73-002 (U. S. Environmental Protection Agency, Washington, D C, July 1973). Available from U. S. Government Printing Office, Washington, D. C. 20i+02 , as GPO Stock No. 5500-00103,

Catalog No. EPl. 2:N69/23/973.

[17] Information on Levels of Environmental Noise Requisite to Protect Public Health and

Welfare with an Adequate Margin of Safety, EPA Report No. 550/9-7^-OOU (U. S. Environmental Protection Agency, Washington, D. C, March 197^). Available from U.

S. Government Printing Office, Washington, D. C. 20^+02, as GPO Stock No. 5500-00120,

Catalog No. EPl. 2:N69/26.

[18] Standard Definitions of Terms Relating to Acoustical Tests of Building Constructions

and Materials, 063^1-73-,- PP 278-28I+, Part I8, 197^+ Annual Book of ASTM Standards

(American Society for Testing and Materials, Philadelphia, 197^).

[19] American Standard Acoustical Terminology, SI.I-I96O (American Standards Association

(now American National Standards Institute), New York, I960)

.

[20] London, A., Transmission of reverberant soiind through single walls, J. Research NBS

h2, 605-615 (19^+9)-

106
London, A., Transmission of reverberant sound through double walls, J. Research NBS

hk, 77-88 (1950).

Standard -Classification for Determination of Sound Transmission Class, eU13-73, pp

728-730, Part 18, I97I+ Annual Book of ASTM Standards (American Society for Testing

and Materials , Philadelphia, 197^)-

Rating of Sound Insulation for Dwellings, ISO/R717-1968 (international Organization

for Standardization, Switzerland, I968).

Sound Insulation of Wall and Floor Constructions , Building Materials and Structures

Report ikk (National Bureau of Standards, Washington, D. C, 1955)-

Berendt , R. D. , and Winzer, G. E. , Sound Insiolation of Wall, Floor, and Door

Constructions, NBS Monograph 77 (l96it).

Berendt, R. D. , Winzer, G. E. , and Burroughs, C. B. , A Guide to Airborne Impact, and

Structureborne Noise Control in Multifamily Dwellings, Report No. HUD-TS-21+ (U. S. Department of Housing and Urban Development, Washington, D. C. , 1967).

Parkin, P. H. , Piarkis , H. J., and Scholes , W. E. , Field Measurements of Sound

Insulation between Dwellings, National Building Studies Research Paper No. 33 (Her

Majesty's Stationery Office, London, I960)

.

Weston, E. T. , Burgess, M. A., and Whitlock, J. A., Airborne Sound Transmission

through Elements of Buildings, EBS Technical Study k8. Experimental Building

Station, Department of Housing and Construction (Australian Government Publishing

Service, Canberra, 1973).

Jain, R. K. , and Mulholland, K. A. , A databank of sound insulation measurements,

Appl. Acous. 6, 133-1^1 (1973).

Gillam, A. J. , An interactive access system for an acoustics databank, Appl. Acous.

7, 35-i+5 (197^).

Sharp, B. H. , A Study of Techniques to Increase the Sound Insulation of Building

Elements, Report No. WR73-5 (U. S. Department of Housing and Urban Development,

1973). Available from National Technical Information Service, Springfield, Va. 22151, as Accession No. PB-222829.

Bishop, D. E. , Reduction of aircraft noise measured in several school, motel, and

residential rooms, J. Acous. Soc. Amer. 3£, 907-913(1966).

A Study — Insulating Houses from Aircraft Noise, Report No. HUD TS-I9 (U. S. Department of Housing and Urban Development, Washington, D. C. I967).

Young, J. R. , Attenuation of Aircraft Noise by Wood-Sided and Brick- Veneered Frame

Houses, Report No. NASA CR-1637 (National Aeronautics and Space Administration,

Washington, D. C, 1970).

Final Report on the Home Soundproofing Pilot Project for the Los Angeles Department

of Airports, Report No. WCR 70-1 (Wyle Laboratories, El Segvmdo, Calif., 1970).

House Noise-Reduction Measurements for Use in Studies of Aircraft Flyover Noise, SAE

Information Report AIR I08I (Society of Automotive Engineers, New York, 1971).

Gilbert, P., Building Research Translation: An Investigation of the Protection of

Dwellings from External Noise Through Facade Walls, NBS Technical Note 710-2 (1972).

This is a translation of: Une etude sur la protection des habituations contre les

bruits exterieurs penetrant par les facades, Cahiers du CSTB (Centre Scientifique et Technique du Batiment) No. 103 (1969)-

107
Buckingham, E. , Theory and interpretation of experiments on the transmission of

soimd through partition walls, Nat. Bur. Standards (U. S.) Scientific Papers 20 , 193-219 (1925).

Chrisler, V. L. , and Snyder, W. F. , Recent so\md-transmission measurements at the

National Bureau of Standards, J. Research NBS,lij_, ikg-fGh (1935).

London, A. , Methods for determining sound transmission loss in the field, J. Research NBS 26, 1119-^53 (19^+1)-

Standard Recommended Practice for Laboratory Measurement of Airborne Sound

Transmission Loss of Building Partitions, E90-T0, pp 583-592, Part I8, 197^ Annual

Book of ASTM Standards (American Society for Testing and Materials, Philadelphia,

197^+).

Standard Recommended Practice for Measurement of Airborne Sound Insulation in

Buildings, E336-T1, PP 705-723, Part I8, I97U Annual Book of ASTM Standards

(American Society for Testing and Materials, Philadelphia, 197^)-

Field and Laboratory Measiirements of Airborne and Impact Sound Transmission, ISO

Recommendation RIUO-I96O (international Organization for Standardization, Geneva,

Switzerland, I96O).

Mariner, T. , Critique of the reverberant room method of measioring air-borne soxind

transmission loss, J. Acous . Soc . Amer. 33_, 1131-1139 (I961) .

Mulholland, K. A., and Parbrook, H. D. , The measurement of sound transmission loss,

J. Sound Vib. 2, 502-509 (I965).

Kihlman, T. , On the precision and accuracy of measurements of airborne sound

transmission, paper F51, Proc . Fifth International Congress on Acoustics (Liege,

1965).

Mulholland, K. A., and Parbrook, H. D. , The measurement of transmission loss, J. Sound Vib. 5., 391-39^ (1967).

Kihlman, T. , Sound radiation into a rectangular room. Applications to airborne

soimd transmission in buildings, Acustica l8_, 11-20 (1967).

Utley, W. A., Single leaf transmission loss at low frequencies, J. Sound Vib. 8_, 256-261 (1968).

de Bruijn, A. , Influence of diffusivity on the transmission loss of a single wall,

J. Acous. Soc. Amer. kj_, (1970) .

Sewell, E. C, Transmission of reverberant sound through a single-leaf partition

surrounded by an infinite rigid baffle, J. Sound Vib. 12, 21-32 (1970).

Holmer, C. I., Factors affecting the comparison of theoretical and experimental

sound transmission loss of panels (abstract), J. Acous. Soc. Amer. i|£, 88-89

(1971).

Utley, W. A., The accuracy of laboratory measurements of transmission loss, J. Sound

Vib. 16, Gk3-(>hk (1971).

SchiLLtz, T. J., Diffusion in reverberation rooms, J. Sound Vib. I6, 17-28 (l97l)-

Nilsson, A. , and Kihlman, T. , Influence of boundary conditions upon the reduction

index of a wall between tyo rectangular rooms, paper 20A1, Proc. Seventh

International Congress on Acoustics (Budapest, 1971)-

108
[56] Kihlman, T. , and Nilsson, A. C, The effects of some laboratory designs and mounting

conditions on reduction index measurements, J. Sound Vib. 2h_, 3^9-36U (1972).

[57] Lang, J. , Differences "between acoustical insu].ation properties measured in the

laboratory and results of measurements in situ, Appl. Acous. 21-37 (1972).

[58] Higginson, R. F. , A study of measuring techniques for airborne sound insulation in

buildings, J, SoimdVib. 21_, ^+05-^+29 (1972).

[59] Bhattacharya, M. C. , and Guy, R. W. , The influence 'of the measuring facility on the

measured sound insulating property of a panel, Acustica 26_, 3^^-3^8 (1972).

[60] Sewell, E. C. , Errors in the measiirement of the sound reduction index of masonry

vails in the BRE laboratory facility, CP ^+7/7^+ (Building Research Establishment,

Garston, Watford, England, 197^)-

[61] Northwood, , T. D. , Transmission loss of plasterboard walls. Building Research Note

No. 66 (National Research Council, Ottawa, Canada, October I968 (revised December

1968 and July 1970) )

.

[62] Bishop, D. E. , and Hirtle, P. W. , Notes on the sound-transmission loss of

residential-type windows and doors, J. Acous. Soc . Amer. k3_, 88O-882 (1968). This

paper only presents, in graphical form, part of the data originally tabulated in

Bolt Beranek and Newman Report 1387, Methods for Improving the Noise Insulation of

Houses with Respect to Aircraft Noise, prepared for the Fed. Housing Admin, under

FHA Contract FH-9^1 (1966). The tabular data are reproduced in Bolt Beranek and

Newman Rept. 1^+60, Literature Survey for the FHA Contract on Urban Noise, prepared

under FHA Contract FH-95^ (1967)- Neither of these BBN reports are generally

available.

[63] Marsh, J. A., The airborne soiond insulation of glass. Part 1, Appl. Acous. k_, 55-70

(1971); Part 2, Appl. Acous. k, 131-15^+ (l97l) ; and Part 3, Appl. Acous. l4_, 175-191

(1971). Also available, in a single report, as Environmental Advisory Service h (Pilkington Bros. Ltd., St. Helena, Lanes., England, 1970).

[6h] Patil, P. G. , Designing glass units for sound reduction, Sound and Vibration 7. (9)

»

38-39 (Sept. 1973).

[65] Utley, W. A. , and Fletcher, B. L. , Influence of edge conditions on the sound

insulation of windows, Appl. Acous. 2_, 131-136 (1969).

[66] Utley, W. A., and Fletcher, B. L. , The effect of edge conditions on the sound

insulation of double windows, J. Soimd Vib. 26, 63-72 (1973).

[67] Cops, A., Myncke, H. , and Lambert, E. , Sound insulation of glass by means of scale

models, Acustica 31, 1^3-1^+9 (197^+).

[68] de Lange, P. A., Sound insulation of glazing with respect to traffic noise, Appl.

Acous. 2, 215-236 (1969)-

[69] Ingerslev, F. , and Nielsen, A. K. , On the transmission of sound through small

apertures and narrow slits, Ingeniorvidenskabelige Skrifter, Nr. 5 (Kobenhavn 19^+^).

[70] Nomura, Y. , and Inawashiro, S. , On the transmission of acoustic waves through a circular channel of a thick wall, Sci. Rept. Tohoku Univ. 12B, 57-71 (1960).

[71] Sabine, H. J., Measurement of soTind transmission through door seals (abstract), J. Acous. Soc. Amer. 33, 83^ (1961).

[72] Bolt, R. H. , Labate, S. , and Ingard, U. , The acoustic reactance of small circular

orifices, J. Acous. Soc. Amer. 21, 9^-97 (19^9)-

109
Thiirston, G. B. , Periodic fluid flow through circular tubes, J. Acous Soc . Amer. 2h , 653-656 (1952).

Wood', J. K. , and Thurston, G. B. , Acoustic impedance of rectangular tubes, J. Acous.

Soc. Amer. 25, 858-860 (1953).

Smits , J. M. A., and Kosten, C. W. , Sound absorption by slit resonators, Acustica 1,

llU-122 (1951).

Gomperts , M. D. , The "sound insulation" of circular and slit-shaped apertures,

Acustica l^i, 1-16 (196^^).

Gomperts, M. C., The influence of viscosity on sound transmission through small

circular apertures in walls of finite thickness, Acustica 15 , I9I- 198 (1965).

Gomperts, M, C, and Kihlman, T. , The sound transmission loss of circiilar and

slit-shaped apertiires in walls, Acustica l8_, IUU-I50 (196T) .

Wilson, G. P. 5 and Soroka, W. W. , Approximation to the diffraction of sound by a circular apertiore in a rigid wall of finite thickness, J. Acous. Soc. Amer. 37 > 286-297 (1965).

Wilson, G. P., Measurement of the transmission loss of a finite-depth aperture, J. Acous. Soc. Amer. 37, 298-307 (1965).

Sauter, A. , and Soroka, W. W. , Sound transmission through rectangular slots of

finite depth between reverberant rooms, J. Acous. Soc. Amer. kj_, 5-11 (1970)

.

Westerberg, G. , On the sealing of circular holes in a thick wall for the purpose of

sound insulation, Appl. Acous. U_, 115-129 (l97l).

Ford, R. D., and Kerry, G. , The sound insulation of partially open double glazing,

Appl. Acous. 6, 57-71 (1973).

Kerry, G. , and Ford, R. D. , The field performance of partially open dual glazing,

Appl. Acous. 7, 213-227 (197^+).

ASHRAE Handbook of Fundamentals (Amer. Soc. Heating, Refrigerating, and Air

Conditioning Engineers, New York, N. Y. , 1972).

ASHRAE Handbook and Product Directory — Systems (Amer. Soc. Heating, Refrigerating,

and Air Conditioning Engineers, N. Y. , 1973).

Strock, C, and Koral, R. L. , (editors). Handbook of Air Conditioning, Heating, and

Ventilating, 2nd Ed. (industrial Press, New York, 1965).

Threlkeld, J. L. , Thermal Environmental Engineering, 2nd Ed. (Prentice- Hall,

Englewood Cliffs, N. J., 1970).

Jennings, B. H. ,• Environmental Engineering, 6th Ed. (international Textbook Co.,

Scranton, Pa., 1970).

McGuinness, W. I., and Stein, B. , Mechanical and Electrical Equipment for Buildings,

5th Ed. (John Wiley and Sons, New York, 1971).

Wood, B. D., Applications of Thermodynamics (Addison-Wesley , Reading, Mass., 1969).

Fanger, P. 0., Thermal Comfort (Danish Technical Press, Copenhagen, 1970).

Jones, W. P., Air Conditioning Engineering (Edward Arnold, London, 1973).

Down, P. G. , Heating and Cooling Load Calculatiorss (Pergamon Press, London, 1969).

110
Givohi, B., Man, Climate, and Architectiare (Elsevier, Amsterdam, I969)

.

Van Straaten, J. F. , Thermal Performa.nce of Buildings (Elsevier, Amsterdam, I96I)

.

Callendar, J. H. , (editor-in-chief), Time-Saver Standards for Architectural Design

Data, 5th Ed. (McGraw-Hill, New York, 197^+).

Van Dusen, M. S., and Finck, J. L. , Heat transfer through building walls. Bur, Stds

.

J. Research 6, ^93-522 (l93l). RP 291.

Robinson, H. E. , Powlitch, F. J., and Dill, R. S., The Thermal Insulating Value of

Airspaces, Housing Research Paper 32 (Housing and Home Finance Agency, 1957).

Robinson, H. E. , Cosgrove, L. A., and Powell, F. J., Thermal Resistance of Airspaces

and Fibrous Insulations Bounded by Reflective Surfaces , NBS Building Materials and

Structures Rept. 151 (1957).

Kusuda, T. , Proposed procedures for determining building heating and cooling loads

for energy calculations, Amer. Soc. Heating, Refrigerating, and Air Conditioning

Engrs. Spec. Bulletin, 1-10 (1968)

.

Miilroy, W. J., Kusuda, T. , and Phillips, C. W. , Survey of digital computer programs

for heating and cooling load calculations, SICCAPUS Bulletin 2_(2), h-Q (1968).

Performance Criteria for Exterior Wall Systems — Final Report, NBS Rept. 9817 to Federal Housing Administration (1968).

Kusuda, T. , Thermal response factors for m\ilti-layer structures of various heat

conditions systems, Amer. Soc. Heating, Refrigerating, and Air- Conditioning Engrs.

Trans. 75, Part I, 2i+6-271 (1969).

Kusuda, T. , Procedure for determining heating and cooling loads for computerized

ener^ calculations, Amer. Soc. Heating, Refrigerating, and Air-Conditioning Engrs.

Spec. Bulletin (1971).

Kusuda, T. , and Powell, F. J. , Use of modern computer programs to evaluate dynamic

heat transfer and energy use processes in buildings, pp ii07-^l8 in Performance

Concepts in Buildings, NBS Special Publication 36I, Vol. 1 (1972).

Powell, F. J., and Robinson, H. E. , The Effect of Moisture on the Heat Transfer

Performance of Insulated Flat-Roof Constructions , NBS Building Science Series 37

(1971).

Kusuda, T. , (editor) , Use of Computers for Environmental Engineering Related to Buildings, NBS Building Science Series 39 (l97l).

Peavy, B. A., Powell, F. J., and Burch, D. M. , Dynamic Thermal Performance of an Experimental Masoniy Building, NBS Building Science Series U5 (1973).

Berthier, J., Building Research Translation: Weak Thermal Points or Thermal

Bridges, NBS Technical Note 710-7 (1973).

Kusuda, T. , NBSLD, Heating and cooling load calc-ulation program, APEC Journal VIII

(6) (Winter 1973/7^).

Petersen, S. R. , Retrofitting Existing Housing for Energy Conservation: An Economic

Analysis, NBS Building Science Series 6h (197U).

7 Ways to Reduce Fuel Consumption in Household Heating. . .Through Energy

Conservation, prepared in cooperation with the Ad Hoc Committee on Fuel

Conservation, Office of the Special Assistant to the President for Consumer Affairs

and the U. S. Dept. of Commerce, National Bureau of Standards.

Ill
[llU] 11 Ways to Reduce Energy Consumption and Increase Comfort in Household Cooling,

prepared in cooperation with the Office of Consumer Affairs, by the U. S. Department

of Commerce, National Biireau of Standards (l9T2).

[115] Standard Definitions of Terms Relating to Thermal Insulating Materials, CI68-6T, pp

11-lU, Part 18, 19'jk Annual Book of ASTM Standards (American Society for Testing and

Materials, Philadelphia, 197^)-

[116] Standard Method of Test for Thermal Conductivity of Materials ^by Means of the

Guarded Hot Plate, CITT-Tl, PP 15-28, Part I8, 197^ Annual Book of ASTM Standards

(American Society for Testing and Materials, Philadelphia, 197^).

[117] Standard Method of Test for Thermal Conductivity of Materials by Means of the Heat

Flow Meter, C518-7O, pp 188-195, Part I8, 197^ Annual Book of ASTM Standards

(American Society for Testing and Materials, Philadelphia, 197^)-

[118] Standard Method of Test for Thermal Conductance and Transmittance of Built-Up

Sections by Means of the Guarded Hot Box", C236-66 (l97l) , PP 56-67, Part iB, I97I+ Annual Book of ASTM Standards (American Society for Testing and Materials,

Philadelphia, 197^)-

[119] Mumaw, J. R. , Calibrated hot box: an effective means for measuring thermal

conductance in large wall sections, pp 193-211, in Heat Transmission Measurements in

Thermal Insulations (R. P. Tye, Ed.), ASTM Special Technical Publication 5^^+ (American Society for Testing and Materials, Philadelphia, 197^)-

[120] Coleman, E. F. , and Heald, R. H. , Air Infiltration through Windows, Natl. Bur.

Stds. Building Materials and Structures Rept. U5 (l9i+0).

[121] Sasaki, J. R. , and Wilson, A. G. , Air leakage values for residential windows, Amer.

Soc. Heating, Refrigerating, and Air-Conditioning Engrs . Trans. 71, Part II, 8I-88

(1965).

[122] Bursey, T. , and Green, G. H. , Combined thermal and air leakage performance of double

windows, Amer. Soc. Heating, Refrigerating, and Air-Conditioning Engrs. Trans. 76 , Part II, 215-226 (1970).

[123] Paulsen, E. , Performance requirements for windows, pp 375-38U in Performance

Concepts in Buildings, NBS Special Publication 36l, Vol. 1 (1972).

[12U] Wilson, A. G. , and Sasaki, J. R. , Evaluation of window performance, pp 385-39^ in

Performance Concepts in Buildings, Special Publication 36l, Vol. 1 (1972).

[125] Standard Method of Test for Rate of Air Leakage through Exterior Windows, Curtain

Walls, and Doors, E283-73, pp 683-687, Part I8, 19^k Annual Book of ASTM Standards

(American Society for Testing and Materials, Philadelphia, 197^).

[126] Flow Measurement, Chapt. k, PTCI9. 5 ;^-1959 , Supplement to ASME Power Test Codes ,- Part 5-Measurement of Quantity of Materials (Amer. Soc. Mech. Engrs., New York,

1959).

[127] Seifert, E. , Schallschutz im Fensterbau, Glaswelt 22, 92-100 (1969)

•

[128] The International System of Units (Sl), NBS Special Publication 330, 197^ Edition.

[129] Some References on Metric Information, NBS Special Publication 389 (1973).

[130] Mechtly, E. A., The International System of Units — Physical Constants and

Conversion Factors (Revised), NASA SP-7012 (National Aeronautics and Space

Administration, Washington, D. C, 1970).

112
Appendix A. Metric (SI) Conversion Factors

In view of the present accepted practice in this country for tuilding technology,

common U. S. units of measurements have been used throughout this paper. In recognition

of the position of the United States as a signatory to the General Conference on Weights

and Measures, which gave official status to the (metric) International System of Units

(si) in i960, and in accordance with the policy of the National Bureau of Standards to promote familiarity with metric units, assistance is given to the reader interested in

making use of the coherent system of SI units by giving conversion factors applicable to

imits used in this publication.

The International System of Units is described in NBS Special Publication 330 [128];

additional references concerning metrication are given in NBS Special Publication 389 [129].

An extensive compilation of factors for converting to SI units has been prepared by Mechtly

[130].

Quantity To convert from To Multiply by

Length inch

foot

meter

meter

0.025^+*

O.30I18*

Area inchp

.foot

2 met erg meter

6.i+5l6 X 10" * 0.09290

Volume foot^ meter'^ 0.02832

Volume flow rate foot^ min 3 -1

meter sec U.TI9 X 10

Speed • foot min.j^''" mile hr

-1

meter sec

^ meter sec 5.08 X

10"-^*

0,i+l;70i+*

Mass pound( avoirdupois

)

kilogram O.U536

Areal Density pound(mass) foot

-2

kilogram meter I+.88I _o

"nminri ( TTia ) foot -3

XL J -L CUIJ, 111 C L. ^ i. 16.02

Force pound force

( avoirdupois

)

newton 1+. 1+1+8

Pressure inch of water

inch of mercury

pascal

pascal

249

3.38 X 10^

Temperatiure Fahrenheit kelvin = t (^F * ^59.6'

Fahrenheit Celsius t, = f

(tp - 32)

Heat Flow Btu (i^hermochemical)

hour watt 0.2929

Specific Heat Btu lb""*" deg F"-^ joule kilogram ^ kelvin 1.000

Thermal Transmittance

and Thermal Conductance

-1 -2

Btu hour foot

deg F~

-2 -1

watt metre kelvin 5.68

Thermal Resistance

-1 2 Btu - hour foot

deg F

-1 2 watt metre kelvin 0.176

*Exactly, by definition.

113
Appendix B. Auxiliary and Filler Walls in Sound Transmission Loss Tests

The sound pressiare level measured in the receiving room, from which the transmission

loss of the test wall is derived, is determined by the combined transmission of the test

wall and the concrete "surround," consisting of the concre4.e partition in which the test

wall is installed. Due to the isolation of the concrete surround, however, transmission

due to flanking into the side walls, floor and ceiling of the receiving room is eliminated.

If it is known or assumed that the amount of sound energy transmitted by the surround is

negligible compared- to that transmitted by the test wall, the transmission loss (TL) of the

test wall is determined by eg. (6).

If the transmission by the surround is not negligible in relation to that by the test

wall, the apparent transmission loss of the test wall as determined by the above formula

will be lower than its true value. The smaller the difference between the TL of the

surroiand and that of the test wall, and the larger the area of the surromd in relation to

the test wall, the larger will be the error in measurement of the TL of the test wall.

Since much of the sound transmission test program involved the relatively small arenas of windows in relation to the total transmitting (wall) area from the source room to the

receiving room, it was necessary to provide as high a transmission loss as feasible for the

wall area (between the two rooms) not occupied by the test item. This was done in two

steps. The first step was to build a "filler wall" occupying the entire 9 x lU ft opening.

The construction of this wall is shown in Figure B-1, B-2, and B-3. One part of the

construction, which happened to be already in place, was a conventional 2 x k in. wood stud

drywall with Donn Products resilient channel and 5/8 in. gypsum board on one side and 5/8

in. gypsum board secured directly to the studs on the other side. The space between the

studs was filled with 3 l/2_ in. of Fiberglas building insulation. This wall had been

previously tested and found to have an STC of 52. The curve of TL versus frequency is

shown in Figure B-2. The side of the wall with the resilient channel was flush with the

surround on the source room side.

To complete the filler wall, additional 2. x h in. stud^ were erected in the opening on separate plates spaced as far as possible from the original wall. The new studs were sur- faced on the outer faces with two layers of gypsum board of 5/8 in. and 1/2 in. thickness

respectively, and the entire cavity space between the two walls was filled with Fiberglas

building insulation. The dissimilar thicknesses were used to reduce the depth of the

coincidence dip characteristic of gypsum board.

The entire filler wall was tested for sound transmission by the usual proced\ire, in

which the area of the test wall, S = 126 sq ft, was used in eq. (6) to compute transmission

loss. The results are shown in Figure B-3, indicating an STC of 63. It was suspected that

the concrete surround, having an area of l60 sq ft, was providing significant flanking

transmission which would make the apparent TL of the filler wall too low.

To check this possibility, a-uxiliary construction was added to the entire area of the

concrete surround on the source room side. This consisted of 2 x U in. wood studs spaced

out from the concrete, with one layer each of 5/8 in. and 1/2 in. gypsum board secured to

the outer faces and the cavity completely filled with Fiberglas building insulation. The

finished surface of the auxiliary wall was l6 in. from the concrete. The gypsum board was continued aro\ind the inner perimeter of the auxiliary wall to meet the filler wall , but a small gap was left at the joint which, in turn, was caulked and taped. The bottom side of

the perimeter was faced with plywood instead of gypsum board to provide a step for access

to the filler wall. The construction is detailed and illustrated in Figures B-k and E-5.

The combination of the filler wall and the improved surround was again tested for

sound transmission. Values of transmission loss can be computed and interpreted from the

measured values of sound pressure level L and L in three different ways.

s r In the first case, the foregoing procedure is followed in which transmission by the

surround is assumed negligible in relation to that by the filler wall, and the area of the

filler wall, S = 126 sq ft, is used in eq. (6). This yields apparent values of TL for the

filler wall as shown in Figure B-6, with an STC of 72. These values can be considered as

Ilk
Figure B-1. Filler wall .after cutting opening for picture 'window.

1. 5/8 IN. GYPSUM BOARD

2. DONN DG-8 RESILIENT CHANNEL

| | | | | |_

3. FIBERGLAS BUILDING INSULATION 125 250 500 1000 2000 4000

4. 2 IN. X 4 IN. STUDS 16 IN. O.C. BAND CENTER FREQUENCY, Hz

Figure B-2. Sound transmission loss vs frequency data for wood stud diywall with resilient

channel and cavity insulation.

115
1. RESILIENT CHANNEL DRYWALL

(SEE FIGURE 2, W-1-71)

2. 1/2 IN. GYPSUM BOARD

3. 5/8 IN. GYPSUM BOARD

4. FIBERGLAS BUILDING INSULATION

5. 2 IN. X 4 IN. STUDS 16 IN. O.C. 125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure B^3. Apparent sound transmission loss vs frequency data for complete filler wall,

concrete surround not covered.

Figure B-k, Auxiliary construction added to concrete surround.

116
Figure B-5. Filler wall and auxiliary construction over concrete surround.

117
true values for the filler wall if transmission by the siorround is assumed negligible. If

transmission by the s\u*round is not negligible, then the apparent TL values for the filler

wall must be considered as minimum.

In the second case, the TL of the surround can be established in the ^ame way by

inserting the area of the surround, S = l6o sq ft, in eq. (6). This will resixLt in

apparent TL values one dB higher at all frequencies than those for the filler wall, with an

STC of 73- This difference results directly from, the relative areas and is given by 10 log

(160/126). The values for the surround can likewise be considered as minimum, or as true

only if the TL of the filler wall is infinite (negligible transmission).

In the third case, the combined area of the filler wall and surround, S = 286 sq ft,

is used to compute TL. This yields TL values k dB higher at all frequencies than the

values computed for the filler wall alone, with an STC of 76. The TL values computed in

this way represent the value which either the filler wall or the sixrround would have if

their TL's were equal at all frequencies. In other words, the total soimd energy

transmitted by the entire surface of 286 square feet is that which would be accounted for

by a single wall of^this area having the computed TL value at each frequency. The minimum

TL values of the filler wall and surround, respectively, and the equivalent TL value of the

filler and surround combined are plotted together in Figure B-7. The latter set of data

will be used to estimate the degree of flanking transmission when testing the windows,

which will be inserted in the filler wall. The true value of TL for the window is given by

the formiila:

= 10 [ T S /S 1 (^-1)

1 wa o s w .

where: t = transmission coefficient of window

wa

= equivalent transmission coefficient of filler wall and surround

S = total area of filler wall and surround, less window area

s S = window area w

If the transmittivity of the filler wall and surround, weighted by their combined area,

in relation to the window area, is much smaller than the transmittivity of the window, then

the second term in the denominator of the above equation can be neglected, and the TL true

value (TLvr) is essentially equal to the apparent value TL^^g_ and is given by eq. (6), using

the window area for S.

118
90

80

70

60

50

40

30

20

AREA BASIS FILLER WALL, 126 ft' X--X SURROUND, 160 ft'

• • TOTAL, 286 ft 2

125 250 500 1000 2000 4000 BAND CENTER FREQUENCY, Hz

Figure B-7. Apparent sound transmission loss vs frequency data for complete filler wall

with auxiliary construction added to concrete wall. The three curves repre- sent computations "based on three different values for the wall area.

119

Appendix C. Detailed Sound Transmission Loss Test Results

Table C-1

Sound Transmission Loss of Exterior Walls

Exterior Finish Cavity Insulation

Resilient

Channel Test No. STC

Wood Siding No No W-4-72 37

Fiberglas Kraft Faced No 54-71 39

Fiberglas Friction Fit No 7-72 39

Alfol Type 2P No 6-72 37

Premium Rock. Wool No 5-72 38

No Yes 56-71 43

Fiberglas Kraft Faced Yes 55-71 47

Stucco Fiberglas Kraft Faced No 50-71 46

No Yes 53-71 49

Fiberglas Kraft Faced Yes 52-71 57

Brick Veneer Fiberglas Kraft Faced No 44-71 56

No Yes 46-71 54

Fiberglas Kraft Faced Yes 45-71 58

121
Table C-2

Sound Transmission Loss of Exterior Doors

Normally Closed Sealed

Door Weather Strip Test No. STC Test No. STC

Wood, flush solid core Brass W-90-71 27 W-91-71 30

Same Plastic 42-72 27

Same, plus aluminum

storm door Plastic 40-72 34 41 -72 42

Wood, flush hollow core Brass 92-71 20 93 -71 21

Wood

,

french door Brass 94-71 26 95 -71 31

FRP panel Plastic 43-72 25 44--72 26

Steel, flush Magnetic 2-72 28 3- 72 28

Notes

:

1. All doors were tested in the same frame except the steel door

,

which was prehung in a different frame.

2. The flush solid core wood door was prehung in frame with brass spring

weather stripping supplied. Other wood doors were trimmed as needed to fit this frame.

3. Plastic weather stripping was substituted for the brass in the same frame.

4. The FRP panel door was slightly oversize and made a very tight fit against

the plastic weather stripping.

122
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Table C-h

Sound Transmission Loss of Walls Containing Wlndo-ws

Wall area, 126 ft; Window area, 26 ft'

Wall alone W J- 11 Li'w' w 9.1 onG Combination

Wall Glazing Test No. STC Test No., STC Test No. STC

Wood siding Single strength W-5^-Tl 39 W-8-T1 28 W-57-T1 35

1 in. insul. glass 39 10-71 3^ 58-71 38

Brick veneer Single strength W-1+1+-71 56 8-Tl 28 1+9-71 35

1 in. insul. glass 56 •10-71 3h 1+8-71 39

125
*'

' Table C-5

Sound Transmission Loss of Windows with Cracks and Openings

6 X 5 ft Picture Window, glazed double strength

Gauged crack around full perimeter = 20.3 ft

Crack Width Test No. STC

0 in. (sealed ) W-7-71 29

9-71 27 1/32 in. 21-71 25

1/16 in. 17-71 21 1/8 in. 15-71 18

1/4 in. 16-71 15

6 X 5 ft Picture Window, glazed 1 in. insulating glass

Gauged crack around half or full perimeter

Crack Width Perimeter Test No. STC

0 in. (sealed) W-10-71 34

1/32 in. Half 20-71 29

1/32 in. Full 19-71 26

1/16 in. Full 18-71 23

1/8 in. Full 14-71 19

1/4 in. Half 13-71 18

1/4 in. Full 12-71 15

C. 3 X 5 ft Wood Double-Hung, glazed 7/16 in. insulating glass.

Lower sash raised by gauged amounts

Condition Test No. STC

Sealed W-31-71 28

Locked 24-71 26 Unlocked 25-71 22 Open 1/32 in. 26-71 20

Open 1/16 in. 27-71 20

D. 3 X 4 ft Wood-Plastic Awning Window, glazed double strength.

Both sashes cranked open by gauged amounts

Condition Test No. STC

Sealed W-64- 71 30

Cranked tight shut 59- 71 27 Cranked open 1/32 in. 60- 71 24 Cranked open 1/16 in. 61- 71 23

Cranked open 1/8 in. 62- 71 19

Cranked open 1/4 in. 63- 71 17

126
Table C-5 (continued)

E. 3 X 4 ft Wood-Plastic Awning Window, glazed 3/8 in. insulating

glass

.

One or both sashes cranked open by gauged amounts

Condition Test No. STC

Sealed W-68-71 28

Cranked tight shut 67-71 24 Upper cranked open 1/32 in. 69-71 24 Both cranked open 1/32 in. 70-71 24 Upper cranked open 1/16 in. 71-71 24 Both cranked open 1/16 in. 72-71 23

Upper cranked open 1/8 in. 73-71 22 Both cranked open 1/8 in. 73A-71 20

127
TABLE C-6 SOUND TRANSMISSION

TEST NO DESCRIPTION

STC 80 100 125

W- 7-71 6 X 5 ft picture window glazed double strength,

single light.

29 24 21 23

W- 8-71 6 X 5 ft picture window glazed single strength, 28 26 21 20

divided lights, 16 panes.

W- 9-71 Same as W-7-71 27 26 21 22

W-lO-71 6 X 5 ft picture window, 1 in glazed insulating

glass.

34 28 26 27

W-11-71 Same as W-8-71 plus storm sash, glazed double

strength, single light, 3 3/4 in separation

between panes.

38 18 21 20

W-12-71 Same as W-10-71 with 1/4 in crack, around full

sash perimeter (crack area/sash area = .0165)

crack depth = 1 13/16 in.

15 20 18 18

W-13-71 Same as W-12-71 but 1/4 in crack around half sash 18 21 20 20

perimeter (crack area/sash area = .00826),

W-14-71 Same as W-12-71 but 1/8 in crack (crack area/sash 19 21 19 19 area = .00825).

W-15-71 Same as W-7-T1 and W-9-71 with 1/8 in. crack around 18 20 17 17 full sash perimeter (crack area/sash area = .00825);

crack depth = 1 3/8 in.

W-16-71 Same as W-15-71 but l/k in. crack (crack area/

sash area = .Ol65).

15 17 16 15

W-17-71 Same as W-I5-71 but 1/16 in crack (crack area/sash 21 21 19 17 area = .00413)

128
LOSS PERFORMANCE DATA

FREQUENCY , Hz

160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 6300

23 21 23 24 24 27 27 28 28 31 32 34 34 30 25 26 31

19 18 21 23 22 25 26 26 26 29 30 31 30 33 30 27 20

21 22 22 24 24 27 27 27 28 30 30 32 32 29 23 26

23 20 24 26 28 33 34 37 36 37 38 39 32 35 41 43 46

21 24 29 28 32 34 36 40 41 46 46 46 47 48 41 42 46

15 16 17 17 17 19 19 18 17 13 13 16 17 14 15 17 18

19 17 19 20 20 23 21 21 19 17 17 19 18 16 19 19 20

18 18 18 20 20 22 22 22 19 16 18 22 21 16 18 19 21

16 17 19 18 17 20 20 21 18 18 15 18 20 17 17 19 21

15 15 16 17 15 17 19 18 16 15 13 14 15 15 15 17 18

18 18 19 20 20 22 23 23 22 21 20 22 22 21 22 24 25

129
TABLE c-6 SOUND TRANSMISSION

TESTNO. DESCRIPTIO'N

STC 80 100 125

W-18-71 Same as W-12-71 but 1/16 in crack (crack area/sash 23 23 22 21 area = .00413)

.

W-19-71 Same as W-12-71 but 1/32 in crack (crack area/sash 26 25 22 21 area = .00206).

W-20-71 Same as W-13-71 but 1/32 in crack (crack area/sash 29 24 24 23 area = .00103).

W-21-71 Same as W-15-71 but 1/32 in. crack (crack area/sash 25 22 21 21 area = .00206).

W-23-71 3 X 5 ft double hung window, 7/16 in. glazed 26 23 22 22

insulating glass, single light, partially sealed

as shown in Fig. C-1.

W-24-71 Same as W-23-71 but not sealed 26 22 20 23

W-25-71 Same as W-24-71 but unlocked 22 21 19 21

W-26-71 Same as W-25-71 but lower sash raised 1/32 in. 20 21 19 21

W-27-71 Same as W-25-71 but lower sash raised 1/16 in. 20 20 18 20

W-28-71 3 X 5 ft double hung window, 7/16 in. glazed 35 23 19 26

insulating glass, single light plus storm sash,

glazed single strength, single sealed separation

between panes: upper 1 1/2 in, lower 2 13/16 in.

W-29-71 Same as W-28-71 but storm sash glazed double 39 22 22 27 strength.

130
LOSS PERFORMANCE DATA

FREQUENCY, Hz

160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 6300

18 19 20 23 21 26 24 24 22 21 22 26 25 22 23 24 26

19 19' 21 23 23- 28 27 26 25 24 27 29 28 26 27 27 29

19 20 20 25 26 29 29 30 28 28 29 32 31 29 30 31 33

18 20 21 22 21 25 24 26 24 25 24 27 27 26 24 26 28

20 22 22 20 20 21 22 25 24 28 31 32 33 34 34 32 34

20 21 21 20 20 21 21 23 24 28 29 30 30 29 30 30 32

18 19 20 18 19 20 21 22 22 25 25 26 24 22 21 24 29

17 17 18 18 18 19 20 21 20 23 23 22 20 19 18 19 24

16 18 19 18 17 18 19 21 20 22 22 22 20 19 19 21 24

20 19 22 24 28 33 36 38 39 43 43 45 48 50 53 50 47

23 25 28 30, 31 35 38 40 40 45 46 47 48 50 49 50 45

131
TABLE C-6 SOU,ND , TRANSMISSION

TESTNO. DESCRIPTION

STC 80 100 125

W-31-71 Same as W-28-71 but no storm sash. 28 23 22 24

W-32-71 3 X 5 ft double hung window glazed double strength, 29 23 21 25

single light, sealed.

W-33-71 3 X 5 ft double hung window, glazed single strength 29 20 20 21

divided, B lights each sash, sealed.

W-34-71 Same as W-32-71 but divided, 8 lights each sash. 30 21 20 23

W-35-71 Same as W-33-71 but single light, unlocked 25 21 18 20

partially sealed as shown in Fig. c-1.

W-36-71 Same as W-33-71 but single light plus storm sash, 36 24 20 26

glazed double strength, single light, separation

between panes: upper 1 7/8 in, lower 3 3/16 in.

W-37-71 Same as W-36-71 but storm sash glazed single 34 23 19 23

strength.

W-38-71 Same as W-35-71 but not sealed, lower sash raised 21 19 17 19

1/16 in.

W-39-71 Same as W-38-71 but lower sash raised 1/32 in. 21 19 17 18

W-40-71 Same as W-35-71 but normally closed, not sealed. 23 21 18 20

W-41-71 Same as W-35-71 but completely sealed. 29 23 20 20

132
LOSS PERFORMANCE DATA

FREQUENCY, Hz

160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 6300

22 24 24 21 23 21 23 26 27 33 36 37 39 40. 40 35 34

2-1 21 22 25 25 28 28 28 29 32 31 33 33 30 27 29 33

18 22 22 23 22 26 27 27 27 30 32 33 33 32 31 30 33

20 23 24 25 25 29 29 28 29 32 32 32 32 31 31 33 35

17 19 18 18 20 23 23 23 23 27 28 30 30 32 31 29 27

22 23 25 28 29 33 37 40 40 46 46 47 48 49 48 48 37

22 18 20 23 28 31 35 38 40 43 44 45 46 50 51 46 41

16 16 17 18 19 20 21 22 22 23 23 23 21 17 18 20 22

17 17 17 19 19 20 22 23 22 23 24 24 21 19 19 20 23

15 18 18 20 19 22 22 23 22 26 27 27 27 26 25 24 26

18 21 21 22 23 26 26 27 27 29 31 32 33 34 33 29 28

133
TABLE C-6 SOUND TRANSMI

ESTNO. DESCRIPTION

W-44-71 Brick veneer wood stud exterior wall, cavity

insulation. See Fig. C-2.

W-45-71 Same as W-44-71 plus resilient channel. See

Fig. C-2.

W-46-71 Same as W-45-71 but no insulation. See Fig. c-2.

W-48-71 Same as W-44-71 but penetrated by W-10-71,

W-49-71 Same as W-44-71 but penetrated by W-8-71.

W-50-71 Stucco wood stud exterior wall with cavity

insulation. See Fig. C-3.

W-52-71 Same as W-50-71 plus resilient channel. See

Fig. C-3.

W-53-71 Same as W-52-71 but no insulation. See Fig, c-3.

W-54-71 Wood siding wood stud exterior wall with cavity

insulation. See Fig.c-4.

W-55-71 Same as W-54-71 plus resilient channel. See

Fig. c-4.

W-56-71 Same as W-55-71 but no insulation. See Fig. c-4.

13k
LOSS PERFORMA.NCE DATA

FREQUENCY, Hz

160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 6300

36 42 46 49 51 54 56 58 61 67 67 69 69 70 73 75 69

39 46 47 52 54 57 58 60 61 69 68 71 71 72 74 77 68

34 41 41 47 50 52 55 59 61 65 66 68 68 69 72 75 67

26 27 30 33 34 38 40 39 38 41 42 45 40 42 49 51 51

27 27 28 28 30 31 33 35 34 36 37 39 40 42 39 37 39

30 42 41 44 43 45 45 46 45 46 48 50 50 50 55 58 62

41 50 49 53 55 58 58 58 58 59 59 60 58 57 60 64 61

32 34 37 41 46 50 50 50 51 54 55 57 55 55 58 62 63

18 28 30 33 34 40 42 45 47 50 50 51 50 50 53 54 53

27 30 35 41 43 49 52 56 58 59 60 61 60 58 60 62 63

22 26 32 35 38 43 45 50 51 56 57 58 56 54 57 59 53

135
TABLE C-6 SOUND TRANSMISSION

TEST NO DESCRIPTION

STC 80 ICQ 125

W-57-71 Same as W-54-71 but penetrated by W-8-71. 35 25 21 19

W-58-71 Same as W-54-71 but penetrated by W-10-71. 38 26 21 18

W-59-71 3 X 4 ft awning window, glazed double strength, 27 21 19 22 both sashes cranked shut

.

W-60-71 Same as W-59-71 but both sashes opened 1/32 in. 24 21 19 20

W-61-71 Same as W-59-71 but both sashes opened 1/16 in. 22 19 20 20

W-62-71 Same as W-59-71 but both sashes opened 1/8 in. 19 19 17 16

W-63-71 Same as W-59-71 but both sashes opened 1/4 in. 17 17 15. 14

W-64-71 Same as W-59-71 but sealed. 30 16 20 21

W-65-71 3 X 5 ft fixed casement window, single light,

glazed double strength.

32 23 21 24

W-66-71 Same as W-65-71 but sealed. 31 23 21 23

W-67-71 3 X 4 ft awning window, 3/8 in. glazed insulating 24 21 22 21

glass, both sashes cranked shut.

136
LOSS PERFORMANCE DATA

FREQUENCY, Hz

160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 6300

20 25 28 29 29 32 33 34 35 38 39 40 41 42 39 37 39

20 24 27 32 32 37 40 42 44 44 45 45 39 41 47 51 51

19 23 25 26 26 28 28 27 26 24 23 27 30 32 31 31 34

18 21 22 23 24 25 24 23 22 20 20 23 26 29 29 31 32

17 20 22 22 23 24 23 23 21 18 19 23 26 27 28 29 31

18 19 19 21 21 22 22 21 18 16 15 22 23 25 25 27 28

13 16 18 18 18 20 19 18 15 13 13 18 20 23 23 23 25

21 23 25 26 26 28 28 28 28 31 32 35 36 35 32 31 36

21 22 25 26 27 29 30 30 32 33 34 36 37 35 30 32 35

20 24 23 26 26 29 29 30 30 33 35 37 36 35 30 31 35

20 24 24 22 20 19 22 25 24 23 23 25 28 33 33 30 31

137
T A B L E C-6 S 0 ~U N D > T R A N S M L S

ESTNO. DESCRIPTION

W-68-71 Same as W-67-71 but sealed.

W-69-71 Same as W-67-71 but upper sash opened 1/32 in.

W-70-71 Same as W-67-71 but both sashes opened 1/32 in.

W-71-71 Same as W-67-71 but upper sash opened 1/16 in.

W-72-71 Same as W-67-71 but both sashes opened 1/16 in.

W-73-71 Same as W-67-71 but upper sash opened 1/8 in.

W-73A-71 Same as W-67-71 but both sashes opened 1/8 in.

W-74-71 3 X 5 ft double hung window, glazed single strength,

single light, locked.

W-75-71 Same as W-74-71 but unlocked.

W-76-71 Same as W-74-71 but sealed.

W-77-71 Same as W-75-71 plus combination storm sash,

glazed single strength, single light, separation

between panes: upper 2 1/4 in. , lower 3 3/8 in.

138
LOSS PERFORMANCE DATA

FREQU ENCY, Hz

160 200 250 315 400 500 613 800 1000 1250 1630 2000 2500 3150 4000 5000 6300

20 25 25 21 19 20 23 26 30 32 33 34 36 37 34 29 31

21 23 22 22 19 18 22 24 23 24 23 25 28 32 34 29 31

21 24 24 22 19 20 22 25 25 22 23 25 27 31 32 30 31

21 25 22 21 19 19 22 25 23 22 23 25 28 32 33 30 31

20 25 24 22 18 19 22 23 23 21 22 23 27 31 32 29 30

18 22 22 21 19 18 21 23 22 18 19 24 26 30 30 29 2?

20 22 21 20 19 19 21 22 20 16 17 22 26 28 30 28 28

17 18 18 22 22 25 25 26 24 27 28 30 28 28 28 26 28

20 19 20 23 22 25 25 26 26 29 29 30 25 25 28 28 30

17 19 21 23 24 25 26 27 27 31 32 33 33 35 36 32 30

15 16 18 20 21 26 30 32 34 37 37 37 36 37 38 37 37

139
TABLE C-6 SOUND TRANSMISSION

TESTNO. DESCRIPTION

STC 80 100 125

W-78-71 Same as W-77-71 but locked 32 19 15 14

W-79-71 Same as W-78-71 but storm sash sealed. 36 20 19 18

W-80-71 3 X 5 ft double hung window, 3/8 in. glazed 25 21 22 23

insulating glass, single light, unlocked.

W-81-71 Same as W-80-71 but locked 26 21 23 22

W-82-71 Same as W-80-71 but locked and sealed • • 26 21 21 23

W-83-71 Same as W-80-71 plus combination storm sash, .33 21 19 19

glazed single strength, single light.

W-84-71 Same as W-83-71 but locked 33 20 17 18

W-85-71 Same as W-84-71 but storm sash sealed. 36 20 19 21

W-88-71 4 X 5 ft casement window, both sashes operable, 30 24 23 24

glazed double strength, both sashes locked.

W-89-71 Same as W-88-71 but both sashes unlocked. 22 17 22 21

W-90-71 3 X 7 ft solid core wood door, mounted in frame, 27 20 24 21

brass weather strip.

iko
LOSS PERFORMANCE DATA

FREQUENCY, Hz

160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 6300

16 19 20 22 23 30 33 36 37 40 40 41 40 40 43 43 40

19 24 25 25 28 33 37 40 40 41 41 42 44 45 48 46 43

21 21 23 18 21 19 2,1 24 23 29 32 31 28 28 30 29 31

21 21 22 19 20 19 21 24 24 29 30 32 33 34 32 30 30

21 23 23 20 21 20 21 24 24 29 33 34 37 37 39 33 32

16 21 24 24 25 30 32 35 37 41 41 42 40 41 45 43 40

17 21 22 24 25 30 32 35 37 41 42 42 42 45 46 44 40

19 25 25 27 29 33 36 39 37 42 43 42 43 47 49 46 43

22 24 24 26 26 29 28 29 28 28 28 32 34 34 31 32 34

19 21 21 23 21 25 23 23 22 21 20 20 23 25 28 28 31

24 27 27 27 27 30 30 28 26 25 25 25 27 28 29 31 35

ll+l
TABLE C-6 SOUND TRANSMISSION

TESTNO. DESCRIPTION

STC 80 100 125-

W-91-71 Same as W-90-71 but sealed into frame. 30 22 22 25

W-92-71 3 X 7 ft hollow core wood door, mounted in frame, 20 13 11 14 brass weather strip.

W-93-71 Same as W-92-71 but sealed into frame. 21 15 16 1^

W-94-71 3 X 7 ft wood french door, 12 lights glazed 26 21 24 20

single strength, mounted in frame, brass

weather strip.

W-95-71 Same as W-94-71 but sealed into frame. 31 19 22 23

W- 2-72 3 X 7 ft hollow steel door, mounted in frame, 28 18 22 23

magnetic weather strip.

W- 3-72 Same as W-2-72 but sealed into frame. 28 18 24 22

W- 4-72 Wood siding wood stud exterior wall. See Fig. C-4. 37 23 19 16

W- 5-72 Same as W-4-72 but with cavity insulation. See 38 23 17 3 6 Fig- C-4.

W- 6-72 Same as W-5-72 but different cavity insulation. 37 22 17 18

See Fig. c-4.

W- 7-72 Same as W-5-72 but different cavity insulation.

See Fig. c-4.

Ih2

37 24 16 13
LOSS PERFORMANCE DATA

FREQUENCY, Hz

160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 6300

22 26 25 28 29 30 30 30 29 31 31 34 32 30 30 31 35

14 14 15 15 17 17 17 15 18 22 22 22 24 27 29 29 30

15 15 15 16 17 18 17 15 18 24 24 " 27 28 30 32 32 33

20 24 25 23 24 28 29 28 28 25 25 23 25 27 28 30 32

20 24 23 24 24 26 29 30 30 32 32 34 35 36 35 35 36

21 25 26 26 27 28 29 31 31 32 27 24 32 36 39 39 38

21 27 28 28 29 30 31 32 33 33 27 24 34 35 37 38 34

16 22 26 33 35 36 39 43 46 50 51 52 51 48 49 51 53

17 27 31 34 35 38 42 45 46 49 51 53 53 50 52 51 54

16 22 26 32 34 38 39 43 46 51 52 55 53 52 52 53 54

16 26 31 36 36 39 41 46 46 49 50 52 51 49 49 50 51

1^3
TABLE c-6 SOUND TRANSMISSION

TESTNO. DESCRIPTION

STC 80 100 125

W-16-72 6 X 7 ft sliding glass door, glazed 3/16 in. 26 20 24 25

safety glass, locked.

W-17-72 Same as W-16-72 but unlocked 26 25 25 25

W-18-72 Same as W-16-72 but completely sealed. 31 24 25 23

W-19-72 3 X 4 ft aluminum casement window, glazed 21 21 19 20

double strength, 'locked.

W-20-72 Same as W-19-72 but unlocked '. . 17 16 15 15

W-21-72 Same as W-19-72 but sealed 31 17 19 24

W-22-72 3 X 4 ft laminated glass, double sheets 1/8 in. 34 22 26 27 glass laminated to inner clear damping layer,

sealed in heavy wood frame.

W-23-72 3 X 4 ft aluminum sliding window, glazed single 24 17 19 21

strength, closed and latched.

W-24-72 Same as W-23-72 plus storm sash, glazed single 22 19 20 22

strength, separation between panes: one side

1/16 in., other side 3/16 in.

W-25-72 Same as W-24-72 but storm sash sealed. 29 19 22 26

W-26-72 Same as W-23-72 but sealed.

ihk

28 17 20 23
LOSS PERFORMANCE DATA

FREQUENCY, Hz

160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 6300

24 23 25 25 24 26 28 29 29 29 28 26. 23 24 26 29 33

23 21 24 25 26 27 27 27 28 29 28 25 23 23 25 29 33

24 25 26 27 28 30 30 31 32 34 34 31 27 30 34 37 39

17 . 16 16 17 16 18 18 19 20 22 22 23 25 28 28 29 31

14 14 13 15 14 15 17 18 18 17 16 15 18 21 25 26 27

20 24 26 26 28 29 29 31 31 34 34 35 35 33 31 32 36

25 26 28 30 30 33 33 33 33 34 35 36 36 38 41 42 44

17 17 17 20 19 22 22 24 22 23 25 29 28 30 31 30 29

17 19 18 19 18 20 19 19 19 22 21 25 26 29 31 30 31

22 23 22 22 22 24 25 26 28 32 33 35 36 38 38 39 37

21 20 20 21 22 24 25 27 27 31 31 34 35 38 38 35 31

lh5
TABLE C-6 SOUND TRANSMISSION

TEST NO DESCRIPTION

STC 80 100 125

W-27-72 3 X 4 ft aluminum single hung window, 7/16 in. glazed insulating glass, locked.

27 14 21 25

W-28-72 Same as W-27-72 but unlocked. 25 16 22 23

W-29-72 Same as W-27-72 but sealed. 30 15 24 25

W-30-72 3 X 4 ft jalousie window, glazed 1/4 in glass,

4 1/2 in wide louvers with 1/2 in overlap,

cranked tight shut.

20 21 13 14

W-32-72 Same as W-30-72 but all horizontal and vertical

joints sealed.

26 20 17 26

W-40-72 3 X 7 ft solid core wood door plus 'aluminum storm 34 20 19 20

door, glazed single strength, main door normally

closed in frame against extruded plastic weather

strap.

W-41-72 Same as W-40-72 but both doors sealed. 42 19 23 28

W-42-72 Same as W-40-72 but without storm door. 27 20 24 28

W-43-72 3 X 7 ft fiberglass reinforced plastic panel

door, mounted in frame, extruded plastic weather

strip.

25 21 23 25

W-44-72 Same as W-43-72 but sealed. 26 19 22 25

Ik6
LOSS PERF,0R1^^ANCE DATA

FREQUENCY, Hz

160 2Q0 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 6300

19 21 22 21 18 22 25 26 26 29 31 32 31 34 38 35

20 22 21 21 18 22 24 25 25 26 28 26 27 29 33 34 33

24 23 23 23 21 24 26 30 30 34 35 37 38 40 42 39 37

13 14 13 16 17 20 18 19 17 19 20 20 21 24 23 25 25

26 26 26 29 29 28 27 26 26 25 25 25 25 27 29 30 33

22 22 24 26 27 33 33 35 35 41 40 36 35 36 37 40

28 29 30 37 37 39 39 43 43 49 48 48 52 54 54 55 54

26 24 28 27 28 29 29 28 26 28 27 25 26 27 27 28 34

23 24 23 25 27 28 27 28 27 27 21 24 28 33 37 40 41

23 25 25 24 24 29 26 27 27 27 22 24 28 33 38 42 42
SEALED

Figure C-1. Regions which were sealed for Test W-23-T1-

1. FACE BRICK

2. 1/2 IN. AIR SPACE, WITH METAL TIES

3. 3/4 IN. INSULATION BOARD SHEATHING

4. 2 IN. X 4 IN. STUDS 16 IN. O.C.

5. FIBERGLAS BUILDING INSULATION

{W-44-71 AND W-45-71 ONLY)

6. NATIONAL GYPSUM RESILIENT CHANNEL

(W-45-71 AND W-46-71 ONLY)

7. 1/2 IN. GYPSUM BOARD SCREWED TO CHANNEL

Figure C-2. Detail of brick-veneer, wood-stud exterior walls.

ll+8
1. 7/8 IN. STUCCO

2. NO. 15 FELT BUILDING PAPER AND

1 IN. WIRE MESH

3. 2 IN. X 4 IN. STUDS 16 IN. O.C.

4. FIBERGLAS BUILDING INSULATION

(W-50-71 ANDW-52-71 ONLY)

5. NATIONAL GYPSUM RESILIENT CHANNEL

(W-52-71 AND W-53-71 ONLY)

6. 1/2 IN. GYPSUM BOARD SCREWED TO

CHANNEL

1. 5/8 IN. X 10 IN. REDWOOD SIDING

2. 1/2 IN. INSULATION BOARD SHEATHING

3. 2 IN. X 4 IN. WOOD STUDS 16 IN. O.C.

4. FIBERGLAS BUILDING INSULATION

(W-54-71 AND W-55-71 ONLY)

3 IN. PREMIUM BRAND PAPER ENCLOSED

BUILDING INSULATION

{W-5-72 0NLY)

ALFOL TYPE 2P REFLECTIVE-TYPE

INSULATION

(W-6-71 ONLY)

3 1/2 IN. FIBERGLAS FRICTION FIT INSULATION

(W-7-72 ONLY)

NATIONAL GYPSUM RESILIENT CHANNEL

(W-55-71 AND W-56-71 ONLY)

1/2 IN. GYPSUM BOARD SCREWED TO

CHANNEL

Figure C-3. Detail of stucco, wood-stud

exterior walls

.

Figure C-h . Detail of wood-siding, woodstud exterior walls.

IU9
Appendix D. Detailed Thermal Test Results

Table D-1. Thermal test data for walls, doors and windows

Test No. Wall Description

Pressure Air Mean Hot Cold Mean Mean' Differ- Leak- Wall Sur- Sur- Hot Cold

ential age . Temp. face face Air Air

Temp. Temp. Temp. Temp.

in. water ft\in °F

TT-001-71 2 X 4 in. studs on 16 in. centers,

1/2 in. gypsum board interior sur- face 1/2' in. wood fiber sheathing

plus 10 in. wide' redwood lap siding

exterior surface. No insulation in cavities.

24.4 58.3

°F 9.4°F

71.2

with Fiberglas 3-1/2 in. Friction

Fit Building Insulation in cavities, polyethylene vapor barrier.

TT-015-71

TT-030-72

TT-031-72

TT-038-72

TT-039-72

TT-042-72

TT-043-72

Alfol Type 2P Insulation inset

stapled in cavities.

Same as TT-014-71 0.50 0.1

Same as above but with Premium Brand 0

3 in. Paper Enclosed Rock Wool Bldg. Insul. in cavities.

Same as TT-030-72 0.25

Same as above but with Fiberglas 0 3-1/2 in. Kraft Faced Building

Insulation in cavities.

Same as TT-038-72 0.25

Same as TT-038-72 "i-ut with gypsum 0 board on Donn Products DG-8

resilient channel.

Same as TT-042-72 0.25

1.2

0.7

0.8

27.9

26.0

24.6

25.7

25.4

25.1

24.8

66.8

67.9

67.6

68.5

67.9

69.3

68.7

-11.0 76.5

-15.9 74.9

-18.2 74.7

-17.0 74.5

-16.9 73.9

-19.1 74.4

-19.0 73.9

-21.7

TT-018-71 Same as TT-001-71 0 27,,6 63,.2 -7.9 77,,1 -20..1

TT-019-71 Same as TT-001-71 0.50 0.8 27,.2 63..0 -8.4 76,.3 -20,.5

TT-002-71 Same construction as above but 0 24,,1 67,,6 -19.2 73,,7 -23,,6

TT-022-71 Same as TT-002-71 0 26.,6 72,.2 -18..9 78..9 -23,.8

TT-023-71 Same as TT-002-71 0. 50 2.1 26.,2 72,,0 -19,,4 78,,8 -23..8

TT-003-71 Same as TT-002-71 0 61.,0 105,.0 17,,0 111,,4 12,,0

TT-004-71 Same as TT-002-71 0. 50 5.2 60.,3 103,,8 16,.7 110..5 12,.0

TT-005-71 Same as TT-002-71 0 99.,5 138,.9 60,.0 144,,7 55,.7

TT-006-71 Same as TT-002-71 0. 50 6.7 98..5 137,.4 59,,6 146..8 55,,6

TT-014-71 Same construction as above but with 0 27.,9 66,.9 -10,,9 76,,5 -18,,3

-18.3

-20.0

-22.9

-21.1

-21.1

-22.0

-22.4

150
Table D-1 (continued)

Net Apparent Effective* Effective* Effective* Effective* Effective*

Test No. Heat Amount of Thermal Thermal Hot Air Cold Air Thermal

Flow Net Heat Conduct- Transmit- Film Film Resistance

Flow due to ance tance Conduct- Conduct- (surface-toAir Leakage (surface-to- (air-to- ance ance surface)

surface) air)

TT-001-71

Btu hr 2280

Btu hr

Btu hr-i

0.267

Btu hr-1

ft-2 °F-1

0.195

Btu hr"l

ft-2 »F-1

1.4

Btu hr"J- ft-2 'F-1

1.5

Btu-j hr ft^ °F

3.73

TT-018-71

TT-019-71

TT-002-71

2370

2390

930

85

0.265

0.266

0.085

0.194

0.196

0.076

1.3

1.4

1.2

1.5

1.6

1.7

3.77

3.76

11.76

TT-022-71 1005 ~ 0.087

TT-023-71 1040 235 0.090

TT-003-71 1020 — 0.092

TT-004-71 1545 550 0.141

TT-005-71 1020 ~ 0.102

TT-006-71 1540 660 0.157

TT-014-71 1495 — 0.152

TT-015-71 1510 10 0.154

TT-030-72 1090 ~ 0.104

TT-031-72 1150 125 0.106

TT-038-72 900 — 0.083

TT-039-72 915 70 0.084

TT-042-72 880 — 0.079

TT-043-72 900 85 0.082

0.078 1.2 1.7 11.49

0.080 1.2 1.9 11.11

0.«081 1.3 1.6 10.87

0.125 1.8 2.6- 7.09

0.091 1.4 1.9 9.80

0.134 1.3 3.1 6.37

0.125 1.2 1.6 6.58

0.126 1.2 1.6 6.49

0.091 1.3 2.1 9.62

0.093 1.3 1.9 9.43

0.074 1.2 1.7 12.05

0.076 1.2 1.8 11.90

0.072 1.4 2.4 12.66

0.074 1.4 2.1 12.20

*Effective refers to the value calculated from measured heat flow. In tests with an imposed pressure

difference, this value includes energy consumed in heating the leakage air from cold side to warm

side temperature.

151
Table D-1. (continued)

test No. Wall Description

Hot Cold Mean Mean

Pressure Air Mean Sur- Sur- Hot Cold

Differ- Leak- Wall face face Air Air

ential aRe Temp Temp. Temp. Temp. Temp.

in. water f t"^min

1 op °F °F °F °F

0 27. 7 70.3 -14.8 78.1 -21.

0.25 22.5 27. 1 68.7 -14.4 75.9 -20.

0 28. 6 71.1 -13. 8 78. 0 -23.

0. 25 30. 2 29. 3 69.0 -10. 3 75.8 -16.

0 27. 6 71.7 -16.4 78.3 -23.

0. 25 32.6 27

.

6 69.1 -13.9 75.3 -19.

0 28. 7 71.8 -14.

3

77.3 -20.

0.25 39.7 28. 2 68.7 -12.3 73.3 -18.

0 — 26. 0 68.1 -16.0 74.5 -22.

0.25 39.7 28. 4 68.2 -11. 3 74.2 -17.

0 27. 2 70.3 -15.9 76.8 -22.

0.25 50.1 32. 4 69.7 -4.9 74.4 -10.

0 — 24. 5 57.1 -8.1 72.1 -20.

0.25 3.2 26. 2 58.1 -5.6 73.1 -17.

0 — 24. 8 61.2 -11.6 72.0 -21.

0.25 4.9 24. 7 61.5 -12.0 72.8 -21.

0 26. 0 66.6 -14.4 72.7 -20.

TT-020-71

TT-021-71

TT-024-71

TT-025-71

TT-026-72

TT-027-72

TT-028-72

TT-029-72

TT-032-72

TT-033-72

TT-034-72

TT-035-72

TT-040-72

TT-046-72

TT-044-72

TT-045-72

TT-049-72

Same as above but with Fiberglas

3-1/2 in. Friction Fit Building

Insulation in cavities, polyethylene vapor barrier, and wood

doublehung window, 3 x 5 ft.,

single glazed sashes, locked.

Same as TT-020-71

Same as TT-020-71 but with window

unlocked

.

Same as TT-024-71

Same as TT-020-71 plus single

glazed wood storm window.

Same as TT-026-72

Same as TT-026-72 but with window

unlocked

.

Same as TT-028-72

Same as TT-020-71 except double

glazed sashes. Same as TT-032-72

Same as TT-032-72 but with

window unlocked.

Same as TT-034-72

Same construction as above but

with wood picture window, 6 x 5 ft. single glazed, divided light.

Same as TT-040-72

Same construction as above but with wood picture window, 6 x 5 ft. double glazed, single light.

Same as TT-044-7 2

Same construction as above but with pre-hung, 1-3/4 in. thick solid

wood flush door, 3 ft. x 6 ft. -8 in. Spring brass weatherstrip on top and

sides, half-round plastic closure strip

at bottom. Fiberglas 3-1/2 in. Friction

Fit Building Insulation in cavities.

152
Table D-1 (continued)

Apparent Effective* Effective* Effective* Effective* Effective*

Amount of Thermal Thermal Hot Air Cold Air Thermal

Test No. Net Net Heat Conduct- Transmit- Film Film Resistance Heat Flow due to ance tance Conduct- Conduct- (surface-toFlow Air Leakage (surface-to- (air-to- ance ance surface)

surface) air)

TT-020-71

Btu hr 1670

-1 Btu hr Btu hr

ft-2 °F 0.156

Btu hr

ft-2 °F 0.133

-1 Btu hr

ft-2 °I 1.7

Btu hr \

ft"-^ °F

^ 2.0

Btu """hr ft*^ °F 6.41

TT-021-71 3560

TT-024-71 1730

TT-025-71 3935

TT-026-72 1410

TT-027-72 4110

TT-028-72 1410

TT-029-72

TT-032-72

TT-033-72

TT-034-72

4610

1420

4665

1465

TT-035-72 5335

TT-040-72 2135

2345

2995

3350

3915

3920

4570

0.340

0.162

0.394

0.127

0.393

0.130

0.452

0.134

0.466

0.135

0.568

0.260

0.293

0.136

0.340

0.110

0.343

0.114

0.401

0.116

0.405

0.117

0.501

0.183

3.9

2.0

4.6

1.7

5.3

2.0

8.0

1.8

6.2

1.8

9.1

1.1

4.6

1.5

5.4

1.7

5.5

1.7

6.4

1.8

6.3

1.8

8.1

1.4

2.94

6.17

2.54

7.87

2.54

7.69

2.21

7.46

2.15

7.41

1.76

3.85

TT-046-72 2260

TT-044-72 1585

310 0.282

0.173

0.198

0.135

1.2

1.2

1.5

1.3

3.55

5.78

TT-045-72 I960

TT-049-72 1380

500 0.212

0.135

0.165

0.117

1.4

1.8

1.6

1.8

4.72

7.41

*Effective refers to the value calculated from measured heat flow. In tests with an imposed pressure

difference, this value includes energy consumed in heating the leakage air from cold side to warm

side temperature.

153
Table D-1. (continued)

Test No. Wall Description

Pressure

Differential

Air Mean

Leak- Wall

age Temp.

Hot Cold Mean Mean

Sur- Sur- Hot Cold

face face Air Air

Temp. Temp. Temp. Temp.

m. water ft-^min-"- °F

TT-050-72

TT-055-72

TT-056-72

TT-059-72

TT-060-72

TT-063-72

TT-064-72

TT-065-72

TT-066-72

TT-069-72

TT-070-72

TT-036-72

Same as TT-049-72 0.25

Same as TT-049-72 but with 0 aluminum sfbrm door.

Same as TT-055-72 0.25

Same as TT-049-72 but with pre- 0 hung, 1-3/4 in. thick steel flush

door with urethane foam core, 3 ft. X 6 ft. -8 in. Magnetic weatherstrip

on top and sides, plastic flaps on bottom.

Same as TT-059-72 0.25

Same as TT-049-72 but with 1-3/4 in. 0 thick, foam filled Fiberglas reinforced plastic panel door, 3 ft. x

6 ft. -8 in. Extruded plastic weatherstrip on top and sides, half-round

rubber closure strip at bottom.

Same as TT-063-72 0.25

2x4 in. studs on 16 in. centers, 0 1/2 in. gypsum board interior surface, 1/2 in. wood fiber sheathing

plus 4 in. brick veneer exterior surface. No insulation.

Same as TT-065-72 0.25

Same construction as TT-065-72 but 0 with Fiberglas 3-1/2 in. building

insulation in cavities, polyethylene

vapor barrier.

Same as TT-069-72 0.25

2x4 in. studs on 16 in. centers, 0 1/2 in. gypsum board interior surface, 3/4 in. styrofoam TG sheathing and 10 in. wide redwood lap siding

exterior surface.

21.7 25.1

27.2

19.9 25.5

26.0

14.9 25.2

25.8

7.1 25.1

26.2

1.8

1.9

25.9

26.6

26.3

27.8

64.6 -14.2 70.8 -20.2

67.7 -13.1 74.8 -20.0

65.3 -14.2 73.3 -19.7

67.7 -15.6 74.6 -20.8

66.3 -15.8 73.4 -20.7

67.3 -15.5 74.2 -20.9

66.2 -15.8 73.9 -20.9

62.7 -10.1 73.5 -19.7

62.4 -10.5 73.4 -19.9

70.5 -17.1 76.1 -21.5

69.9 -17.2 75.6 -21.6

67.1 -11.5 75.9 -20.1

TT-037-72 Same as TT-036-72 0.25 1.7 27.2 66.4 -12.0 75.4 -20.5

15U
Table D-1 (continued)

Test No. Net Heat

Flow

Apparent Amount of Net Heat

Flow due to Air Leakage

Effective*

Thermal

Conductance

Effective*

Thermal

Transmittance

Effective* Effective*

Hot Air Cold Air

(surface-to- (air-tosurface) air)

Film

Conductance

Film

Conduct- ance

Effective*

Thermal

Resistance

(surface-tosurface)

TT-050-72

TT-055-72

Btu hr

3200

1200

Btu hr 2135

-1 Btu hr ^ Btu hr~^ Btu hr~l

ft-2 °F-1 ft-2 °F-1 ft-2 °F-1 0.314

0.118

0.279

0.100

4.1

1.3

Btu hr"l

ft-2 °F-1

4.3

1.4

Btu

ft2 hr

3.18

8.47

TT-056-72 2770

TT-059-72 1110

2000 0.277

0.105

0.237

0.092

2.7

1.3

3.9

1.7

3.61

9.43

TT-060-72 2390

TT-063-72 1115

1515 0.231

0.107

0.202

0.093

2.7

1.3

3.8

1.7

4.33

9.35

TT-064-72 1645

TT-065-72 1795

725 0-159 0.138 1-7

0.196 0.153 1.3

2.6

1.5

6.29

5.10

TT-066-72 1885 180 o.205 0.160 1.4 1-6 4.88

TT-069-72 925 — 0.084 0.075 1-3 1.7 l^-^O

TT-070-72 1045 200 0.095 0.085 1.5 ^-9 10.53

TT-036-72 1495 " 0.151 0.124 1-3. 1-4 6.62

TT-037-72 1580 175 0.160 0.131 1.4 1.5 6.25

*Effective refers to the value calculated from measured heat flow. In tests with an imposed pressure

difference, this value includes energy consumed in heating the leakage air from cold side to warm

side temperature.

155
Appendix E. Detailed Air Infiltration Test Results

Table E-1

Air Infiltration of 3 x 7 ft Exterior Doors

Doors normally closed and latched

3 -1 Air Flow ft min

0.1 0.3 O.T

Weather Strip

Brass

Plastic

Plastic

Brass

Brass

Plastic

Magnetic

in. water in. water in. water

h.6

9.V

7.5

5.3

5.6

6.6

10.2

19.8

17.2

8.9

11.^

l+.O

15.

18.2

35.0

31.0

13.0

19.9

8.5

28*

Door

Wood, flush solid core

Same, plus aluminum storm

door

Wood, flush hollow core

Wood, french

FRP panel

Steel, flush

*extrapolation

Notes

:

1. All doors were tested in the same frame except the steel door, which was prehung in a different frame.

2. The flush solid core wood door was prehung in frame with trass spring

weather stripping supplied. Other wood doors were trimmed as needed to

fit this frame.

3. Plastic weather stripping was substituted for the "brass in the same frame.

h. FEP panel door was slightly oversize and made very tight fit against

plastic weather stripping.

156
o

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CO

on ro

0\ CO On

00o o

CM

00 00 CT\ 01 rH H

IS

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oi

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•H

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•H

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tsl ce

C o •H

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+J

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0) -p •H (1) 00

O o -3- CM oo < Ai > O o LTN V£) oo O C3N (M ON O CM iH

1-3 •H

rHO VD MD

HH CvJ 0\ 11 CM

O iH 00 OJ LTN H 1 S

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-pc

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00

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IT.

c^O

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CM

t/N

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oo

CM t—

Ol 00 o

ir\

MD 00 MD o

ir\ H

VDHCOHVD

CM

-dHO

00 C3N

VDH

00I X

X

VD 00 OO

tiD H

CO o

CMOo

C\J

ro

rH

CM COoO

•HPO

(Uftu

a ^

•H VD

C

Ha tu •H ft

t--

O 1 -dtn C >,

Ti •iH rH

r-l ;i

-p -P

tH

C

-d- -d- J- CtJ X X X !>>

i-f OO 00 00 H

03 •H

HJ -P cd a ft

(U6 Jh

01 0)

tn >

bO o C

0) <u bO H •rH C

(1) tn •H

iH ^

b0O

O

C rH o

ft •H Ctf

H o CO

-P•H

OJU

lie

O

•H

-p

aJ rHO

ft

cdU

-PX

<U *

157
Table E-3

Air Infiltration of Windovs vith Cracks and Openings

6 X 5 ft Pictixre Window

Gauged crack around partial or full perimeter ' •

Air Flow (ft^ min""''

Crack width

1/32 in.

l/l6 in.

1/8 in.

1/k in.

per foot crack length)

0.1 in. water 0.3 in. water O.T in. water

l.T

U.8

10.8

11.0

ll.h

18.8

3.65

9.0

9.3

19.0-

20.

U

33.0

35.2

35.7

6.8*

31.2

52.0*

*extrapolation

B. 3 X i+ ft Wood-Plastic Awning Window, glazed double strength

Upper and lower sashes opened by gauged amounts at bottom

Opening

Cranked tight shut

1/32 in.

l/l6 in.

1/8 in.

Air Flow (ft-^ min ''') 0.1 in. water 0.3 in. water 0.7 in. water

5.2 10. i+ IT. 3

10.3 19.9 29.0

IT. 3 32. U I46.5

50.9 9^.9

158
NBS-1 14A (REV. 7-73)

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4. TITLE AND SUBTITLE

Acoustical and Thermal Performance of Exterior

Residential Walls, Doors and Windows

5. Publication Date November 197 5

6. Performing Organization (-ode

7. AUTHOR(S) H.J. Sabine, M.B. Lacher , D.R. Flynn, and T.L. Quindry

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