UNITED STATES DEPARTMENT OF COMMERCE • J

esse H. Jones, Secretary

NATIONAL BUREAU OF STANDARDS • Lyman J. Briggs, Director

• BUILDING MATERIALS

National Bureau of Standards ^yi^ STRUCTURES

FEB 6 1941

SUPPLEMENT TO REPORT BMS17

Sound Insulation

of ^ V

Wall and Floor Constructions 'P'^

'l^f^'^*

by V. L. CHRISLER q.^

'-^ ^vv.'?'

ISSUED DECEMBER 20, 1 940

This supplement reports the results of sound-transmission measurements made on a number of additional types of construction since the issuance of the original report in March 1939.

UNITED STATES GOVERNMENT PRINTING OFFICE • WASHINGTON • I 94O

FOR SALE BY THE SUPERINTENDENT OF DOCUMENTS, WASHINGTON, D. C. • PRICE 5 CENTS
PANEL 170

Panel 170.—Two-inch solid plaster partition; Yi-inch channel studs; perforated gypsum lath; gypsum, plaster; smooth,

white finish.

PANELS i7IA,B,C, 172

Panel 171A.—Two-inch solid plaster partition; fi-inch channel studs; expanded metal lath; gypsum plaster; smooth,

white finish. Panel 171B.

Same construction as panel 171 A. Panel 171C.

Same construction as panel 171A.

Panel 172.—Two and one-half inch solid plaster partition; Y^-inch channel studs; expanded metal lath; gypsum, plaster; smooth, white finish.

->V//////y////////%^vyZ^^

PANEL 1 73

A

Panel 173A.

Hollow tile panel constructed of 4- by 8- by 16-inch partition tile, two cells.

(Tiles were made ol pumice and portland cement. Partition was plastered on both sides with a brown coat of gypsum plaster, and had a smooth

white finish; thickness of plaster H inch.)

'

P.ANEL 173B.

Same as panel 173A, but it was plastered on one side only.

Panel 173C.

Sa^ne as panel ITSA, hut it was not plastered.

(Note the poor Insulating properties of this panel. This was caused by the large number of pores extending through the walls of the tiles.)

» t .-» T d

• » «.

PANEL 174

Panel 174.Wood studs; Steeltex lath with paper backing nailed to studs with special nail; scratch and brown coats of gypsum plaster; smooth, white finish; thickness of grounds % inch.

PANEL 175

Panel 175.—Wood studs staggered; expanded metal lath; scratch and brown coats of gypsum plaster; smooth, white

finish; thickness of grounds % inch.

[2]
Table 1.

Soynd-lrannsm.inKion Ioh.h- wall niniciuren

Transmission loss (in decibels at rcc(|iiciic'ies (cycles per secondj

1 tXlixil IN U

.

A\'craKi'

128 192 256 384 512 768 1,024 2,048 •1 ,096 256 to 128 to

1,024 I 4,096

SOLID PLASTEli

170 30. 2 27. 7 33. 2 35. 2 30. 6 32. 7 37. 9 47. 6 53. 0 33. 9 36. 5 19. 4

171A 35. 9 31. 5 30. 1 31. 6 33. 8 35. 5 39. 3 46. 9 54. 0 34. 1 37. 6 16. 4 171B 29. 2 29. 9 25. 6 30. 4 30. 5 33. 5 37. 0 46. 4 53. 8 31. 4 35. 1 17. 7 171C 35. 2 33. 3 22. 3 31. 6 31. 3 30. 8 37. 7 46. 7 54. 9 30. 7 36. 0 18. 8 172 34. 3 26. 4 33. 0 36. 8 34. 6 37. 4 43. 2 50. 5 56. 9 37. 0 39. 2 22. 4

HOLLOW TILE

173A 32. 3 32. 4 33. 5 34. 0 36. 2 36. 2 39. 0 41. 6 51. 8 35. 8 37. 4 2.5. 3

173B 30. 9 26. 9 27. 4 35. 8 34. 6 33. 1 35. 9 40. 2 46. 6 33. 4 34. 6 20. 4 173C 7. 9 7. 5 5. 2 7. 3 8. 6 12. 2 14. 1 18. 5 17 4 9. 5 11. 0 15. 5

WOOD STUDS

174 30. 0 27. 3 24. 8 31. 0 34. 5 37. 3 38. 2 38. 0 53. 8 33. 2 35. 0 12. 6

176 43. 8 46. 6 47. 4 47. 7 47. 4 49. 9 50. 0 52. 1 63. 4 48. 5 49. 8 19. 8

27716fi°—40 [ 3 ]
4 1^

PANEL 176

Panel 176.—Wood studs; perforated gtjpsum lath attached to studs with clip consisting of a coiled spring and a piece

of heavy wire extending across the face of the gypsum lath and interlocking with the adjoining clip: scratch and

brown coats of gypsum plaster; smooth, white finish; thickness of plaster inch.

PANEL 177 Panel i78

Panel 177.—Wood studs; gypsum lath attached to studs with clip, as shown in drawing (the nail went through the edge of the gypsum lath holding it and the clip jirtnly against the stud); scratch and brown coats of gypsum plaster; smooth, white finish; thickness of plaster inch. Panel 178.—Wood studs; gypsum lath attached to studs with clip, as shown in draiving (the nail held only the back of

the clip against the stud and allowed a small moveynent of the gypsuiu lath); scratch and brown coats of gypsum

plaster, stnooth, white finish; thickness of plaster y% inch.

Panel I79A panels i79B,e panel 179 d

Panel 179A.—Wood studs; Ys-inch, three-ply plywood ivas attached to both sides.

(A light weight cotton fabric was applied to one side with casein glue and a heavy cotton duck to the other side.) Panel 179B.

Same as panel 179 A, but a 4-inch cotton bat, which had been flameproofed, was placed in the air space between the studs. Panel 179C.

Same as panel 179B, but a 1-inch cotton bat, which had been flameproofed, was used in place of the 4-inch bat. Panel 179D.

Same as panel 179A, but a strip of 4-inch flameproofed cotton bat was cut, having a width equal to the depth of the studs, and these strips were tacked to each side of the studs.

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Table 1.

Sound-trans miunion loss—wall structures ( 'dul imu'd

Transmission loss (in deoihels at frequencies (cycles per second)

128 192 256 384

Average

512 768 1, 024 2, 048 4, 096

256 to

1, 024

128 to

4, 096

WeiKlit

WOOD STUDS—Continued

40. 0 42. 0 41. 9 46. 6 47. 7 49. 3 47. 5 54. 0 65. 5 ! 46. (i 48. 3 i 16. 4

19. 0

33. 4

14. 6

13. 8

14. 6

13. 0

23. 9

42. 1

20. 2

26. 7

24. 4

22. 6

28. 8

42. 4

27. 6

33. 0

45. 6

33. 2

32. 8 36. 9

28. 5 36. 9

31. 4 36. 7

35. 0

45. 1

29. 1

33. 5

31. 1

33. 7

39. 1

46. 1

34. 3

39. 3

38. 1

38. 3

41. 6

46. 3

37. 5

41. 7

42. 6

41. 9

42. 4

47. 8

43. 3

46. 3

49. 1

46. 8

59. 9

63. 8

39. 7

44. 1

46. 0

44. 7

35. 5 35. 9

45. 1

32. 3

36. 8

35. 4

36. 4

45. 8

31. 1

35. 0 4. 83

34. 6 4. 63

34. 3 4. 74

[5]
Panel i80a PANELS 180 B.C

Panel 180A.

Floor panel, 2- by 6-inch wood joists; scratch and brown coats of gy-psum -plaster applied on expanded

metal lath for ceiling; smooth, white finish; grounds % inch thick. (The floor consisted of a subfloor; 2- by 2-inch sleepers, 16 inches on centers, and a hardwood finish floor.) Panel 180B.

Same as 180A, but a ji-inch Balsam Wool was laid on the subfloor and the 2- by 2-inch sleepers were

attached with Gorman clips. Panel 180C.

Same as panel 180B, but 1-inch Balsam Wool was used in place of the Yo-inch Balsam Wool.

PANEL I80D PANELS ISOEF

Panel 180D.

Same as panel 180A, but strips of Nuwood ji-inch thick and 6 inches vnde were placed under the 2- by S-inch sleepers. (The sleepers were attached with Gorman clips. Strips of Balsam Wool 1-inch thick by 16 inches wide were placed between the sleepers.) Panel 180E.

Same as panel 180A, except y,-inch Balsam Wool was laid on the subfloor and on this were placed small squares (2]/2- by 2}^- by Yi-inch thick) of Nuwood, spaced 16 inches on centers in each direction; the 2- by 2-inch

sleepers were laid on top of these squares and held in position by a metal strip over the sleeper at each square; the hardwood floor was applied on the sleepers as before. Panel 180F.

This floor panel was the same as panel 180E, but 1-inch Balsam Wool was used instead of yi-inch material.

Panel 181.

Heavy wooden door, approximately 2y2 inches thick: special hardware: rubber gasket around sides and

top; special felt strips which pushed down from the bottom of the door as it was closed, thus elimiiiating any crack under the door. Panel 182.

Approximately same as -panel 181, but manufactured by another firm.

[6]
Table 2.

Sound-iranamission loss—floor xtriiclnres

Panel No.

Transmission loss (in decibels) at frequencies (cycles pei sccoruij

'I'ap- I)ing Weight

128 192 256 384 512 768 1, 024 2, 048 4, 096

AvoraRe

256 in j 128 to 1,021 4,090

^\<i()l) .loisTS

180A

Ibifl ' 35. 3 22. 6 24. 3 31. 5 34. 1 39. 3 41. 9 50. 4 62. 0 34. 2 37. 9 10. 3 16. 3

180B._ __ 32. 5 37. 3 37. 9 46. 2 48. 3 52. 4 55. 1 64. 6 76. 0 48. 0 50. 0 1.5. S 16. 6 180C 35. 0 37. 6 37. 4 47. 9 48. 9 51. 6 54. 7 63. 9 75. 4 48. 1 50. 3 18. 7 16. 7

180D 37. 1 38. 1 39. 0 46. 9 48. 5 52. 0 54. 8 62. 6 74. 9 48. 2 50. 4 17. 6 16. 7

180E 32. 0 32. 2 33. 1 41. 3 44. 5 49. 4 51. 9 59. 9 72. 2 44. 0 46. 3 13. 4 16. 6

180F 29. 5 36. 2 35. 5 46. 1 48. 1 51. 2 54. 2 62. 9 74. 8 47. 0 48. 7 1.5. S 16. 7

Table 3.Sound-transmission loss—door structures

Panel No.

Transmission loss (in decibels) at frequencies (cycles per second)

Weight

128 192 256 384 512 768 1,024 2,048 4,096

Average

256 to 128 to 1,024 1 4,096

DOORS

181 23. 1

30. 4

25. 6

30. 5

25. 9

29. 5

27. 6

28. 6

28. 9

23. 7

29. 5

24. 7

26. 5

26. 3

32. 8

36. 7

33. 1

3(i. 5

27. 7

26. 6

28. 1

29. 7

lb/ft 2

182 12. 5 o

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