Document zz1VzqprOD2Vz8MGQvrdX78p7
m170
CHAPTER 9
1954 Guide
Table 1. Conductances'(C) for Surfaces , and Air Spaces
All conductance values expressed in Btu per (hour) (square fool) (Fahrenheit degree
temperature difference):
Position of Surface
Direction of Heat Flow
Vertical..................................................................
Upward Downward
Horizontal
SurfaceEmissivity
. e 0.83
1.95 1.21 1.52*
= 0,05
' 1.16 0.44 0.74
Section B. Conductance of Vertical Spaces at Various Mean Temperatures
Mean Temp Fahr Deg
20 40 60 80
100 120 140
Conductances of Air Spaces for Various Widths in Inches
0.128
2.300 2.470 2.650 2.819
2.990 3.167 3.340
0.250
1.370 1.480 1.590 1.702
1.813 1.928 2.035 .
0.364
1.180 1.288 1.390 1.492
1.600 1.700 1.800
0 493
1.100 1.193 1.295 1.390
.
1.486 1.580 1.680
0.713
1.040 1.125 1.210 1.295
1.380 1.467 1.550
1.00
1.030 1.112 1.195 1.280
1.362 1.445 1.530
1.500
1.022 1.105 1.188 1.270
1.350 1.435 1.519
Section C. Conductances and Resistances of Air Spaces Faced on One Surface with Reflective Insulations
Location and Position of Air Space
Direction of Heat Flow
Temp4* Diff Fahr Deo
Winter Summer
Conductance (C)
No. of Air Spaces 1 2 ^3 "
Resistance*
G)
No. of Air Spaces
1 23
Rafter Space (8 in.) Horizontal Horizontal
Horizontal Horizontal
30 deg slope 30 deg slope
30 deg slope 30 deg slope
Stud Space (3* in.)
. Vertical1' Vertical
Vertical-^ Vertical
Vertical
Down Up
Down Up
Down Up
Down Up
45 45
45 45
1
Horizontal Horizontal
Horizontal Horizontal
Horizontal
30 40
30
0.10 0.27
0.07 0.17
10.00 14.29 3.70 5.88
25
0.09
0.06
11.11 16.67
25
0.24
0.16
4.17 6.25
0.15 0.25
0.10 0.17
6.67 4.00
10.00 5.88
25 25
0.13 0.23
0.09 0.14
7.69 4.35
11.11 7.14
0.34
0.23
0.13
2.94
.4.35
7.69
15 20
0.32
0.18
0.11
3.13
5.56
9.09
0.46
2.17
A.S.H.V.E. Transactions, Vo). 44, 3938, p. 5J3.) A.S.H.V.E. Research Report No. 825--Thermal Resistance of Air Spaces, by F. B. Rowley and A. B.
Algren (A.S.H.V.E, Transactions, Vol. 35, 1929, p. 165).
c Thermal Test Coefficients of Aluminum Insulation for Buildings, by G. B. Wilkes, F. G. Hechler and ;
E. R. Queer (A.S.H.V.E. Transactions. Vol. 46, 1940). d Temperature difference is based on total space between plaster base and sheathing, flooring or roofing. '!
* These air space conductance and resistance values are based on one reflective surface (aluminum) hav-r " ing an emissivity of 0.05 facing each space, and are based on total space between plaster base and sheathing; j
flooring or roofing. The rafter and stud spaces are divided into equal spaces.
f Stud space is lined on plaster base side with loose paper with aluminum on surface facing air sp&oe. i
The resistance of the small air space between the piaster base and paper was 0.43,
*,
9 Radiation and Convection Across Air Spaces in Frame Construction, by G. B. Wilkes and C. M. F* ;
Peterson (A.S.H.V.E. Transactions, Vol. 43, 1937, p. 351).
* The recommended surface conductance foor cCaHlICcuUUlalVtilnUgg hneeaat-t losses for oswtiull air for non-`refle.-c--t-i-v---e---s--u---rfacJe-s is 1.65 Btu. For a 15 mph......w....i.n...d......v...e...l.o....c. ity, the recommende--d* value b e6.n0 TB>tu... These coefficients owjeorwedwe-- v
rived from Fig. 4, which was based on tests conducted at the University of Minnesota, and apply to v
, Mi
Heat Transmission Coefficients of BiiUdingpMaterials
171
( )Table 2. Conductivities k and Conductances (C.) of Building and
Insulating Materials .
These constant, are expressed in Btu per (hour) (square foot) (Fahrenheit degree temperature difference). Lonductmires (kj are per tnch thickness and conductances (C) ore for thickness or construction stated, not per inch thickness.
Material
Description
P t=4
D o
eat
oa' Conduct
O ivity or e Conduct s< ance
Resistance
G) G)CD
J
>
3Z
b s a H
z<
(i)
Per i ' For
(C)
Inch | Thick
Thickr ness j
ness Listed
! j
>f3
i
aa
OS
e>
i<
BUILDING BOARDS (Non-Insulating)........
FRAME CONSTRUC
TION
COMBINA
TIONS................
Compressed cement and as
bestos sheets.......................... Corrugated asbestos board.. Pressed asbestos mill board..
Gypsum board---gypsum between layers of. heavypaper......................
4 in. gypsum board................
4 in. gypsum board..-............. 4 in. gypsum board................
118 119
20.4 no
60.5 86 i,
62.8
53.5 90
1 in. fir sheathing and build-
ing paper................................ -- 1 in. fir sheathing, building
paper and yellow pine lap
siding...................... ...
.--
1 in. fir sheathing, building
paper and stucco.................. -- Pine Isd siding And huildin^
paper, siding 4 in. wide___ --
Yellow pine lap siding..........
30
. 20 20 .16 --
4.1 0.48 0.84
1.41
3.73 2.82 2.60
-- 0:86
_ 0.50
---
_.
.--
0.82
0.85 1.28
0.24 2.08 1.19
0.71
--
_
--
_
--
u)
<v
(3)
0.27
0.35 0.38
(3) (1)
1.16 (4)
2.00 1.22
(4) (4)
0.78 (4)
masonry materials Brick.........................................
Damp or wet.....................
Common yellow clay -brick. One tier yellow common
clay brick, one tier face brick, approx. 8 in. thick..
-- --
Clay Tile Hollow..
2 in; Tile, 4 in. plaster both
sides..................................
4 in. Tile, 4 in. plaster both
sides....... .................
6 in. Tile, 4 in. plaster both
sides.;.....................
.8 in. lile, average of 8 types
(Walls No. 59. 63. 64. 66.
67, 90. 91. 92).......................
12 in. Clay tile wall: 8 in. x
5 in. x 12 in. and 4 in. x
5 in. x 12 in...
1
120.0 127.0 124.3
--
5.0* -- .4.8
--
no _ _100
105 --
1- --
-- 0.77
1.00 0.60 0.47 0.52
0.26
0.21
-
_ _ _
--
-
(2) - (4)
1.30 (4)
1.00 1.67 2.13
(2) (2) (2)
1.92 (4)
3.84 (4)
Authorities:
1 National Bureau of Standards, tests based on samples submitted by manufacturers.
*A. C. Willard, L. C. Lichty and L. A. Harding, tests conducted at the University of Illinois.
* J. C. Peebles, tests conducted at Armour Institute of Technology, based on samples submitted by manu-
tacturers-
..
4 F. B. Rowley, et al, tests conducted at the University of Minnesota. `A.S.H.V.E. Research Laboratory.
1 E. A. AUcut, tests conducted at the University of Toronto. ...* See Thermal Conductivity of Building Materials, by F. B. Rowley and A. B. Algren (University of Minnesota Engineering Experiment Station Bulletin No. 12).
Heat Transmission Through Insulation' as Affected by Orientation of Wall, by F. B. Rowley and C. L. Lund (A.S.H.V.E. Transactions, Vol, 49, 1943, p. 331).
c The Effect of Convection in Ceiling Insulation, by G. B. Wilkes and L. R. Vianey (A.S.H-VJ5. Trans actions. Vol. 49, 1943, p. 196).
n 1See A.S.H.V.E. Research Report No.- 915--Conductivity of Concrete, by F. C. Hougbten and Carl ^utberiet (A.S.H.V.E. Transactions. Vol. 38. 1932, p. 47).
See Heating, Ventilating and Air Conditioning, by Harding and Willard, revised edition, 1932. 1 See BMS13, U. S. Department of Commerce, National Bureau of Standards, Washington, D. C.
. . Hoofing, 0.15 in. thick (1.34 lb per square loot), covered with gravel (0.83 lb per square foot), combined lD,ckness assumed 0.25.