Document rxVX6xBQYzQndXxM530oOaR9V
98
CHAPTER 9
1959 Guide
Table 3 .... Surface Conductances and Resistances for Stilt Air
AO conductance value* expressed to Btu per (hr) (sq ft) (F deg temp <ff)
SECTION A. Surfoce Conductances for StiD Air*-
.SECTION 8 Reflectivity and Emotivity Vaiues of Various Surfoce*' and
Effective Emotivities of Air Spoces
Surfoce Emfetivily
Potitioa of Surfoce
Direction of Nocv-
Hecf Flow reflectrve Reflective Reflective t - 0.90 = 0.20 s - 0.05
C RC R CR
Surfoce
Effective Emmjvtfy E of Air Space
Reflectivity in percent
Average Eetistinty With one
surface hav
With both
ing eab- surfoce* of
smty and emotivity <
ofher 0.90
Horizontal.............. Upward 1.63 0.61 0.91 1.10 0.76 1.32 Aluminum foil, bright.... 92 to 97 0.05
Sloping--45 deg.. Upward 1.60 0.62 0.88 1.14 0.73 1.37 Aluminum sheet................... 80 to 95 0.12
Vertical.................... Horizontal 1.46 0.68 0.74 1.35 0.59 1.7C Aluminum coated oaDer. polished.............................. 75 to 84 0.20
Sloping--45 deg... Downward 1.32 0.76 0.60 167 0.45 2.22 Steel, galvanized, bright.. 70 to 80 0.25
1.08 0.92 0.37
4.55
Building materials; wood, paper, glass. masonry.
nonmetailic paints.........
5 to 15 / 0.90
0.05 0.12 0.20 0.24
0.82
0.03 0.06 0.11 0.15
0.82
* For ventilated attics or epeeea above ceilings noder summer conditions (beat flow down) see Table 17. b Conductances are for surface* of the statedemotivity tseinf surroundings having an emotivity equal to 0.9 and at thesame temperature at the ambient air. Values are baaed on a surface-sir temperature difference of 10 de and lor surface temperature of 70 F. (See Table 4 for surface conductances for moving air.) * See also Chapter S, Table 3.
SECTION C. Thermal Conductances and Resistances of a Plane*-" Air Space*
Position of Air Space
Heat Haw
. Air Space
Thermal Conrfuctance-C Value of E<-*
Thermal Retistance-R Value of E
Thickness ,* Mean temp,1 F Temp diff* deg 0.05 0.2
0.5 0.82 0.05 0.2 0.5 0.82
Horiz.
Up
H to4
50
10 0.41 0.55 0.82 1.11 2.44 1.83 1.22 0.90
50
* 30
0.54 0.68 0.95 1.24 1.84 1.47 1.05 0.80
00 10 0.41 0.58 0.92 1.28 2.47 1.73 1.09 0.78
45 Slope
Up
H to 4
50 50 90
10 0.35 0.49 0.76 1.05 2.84 2.05 1.31 0.95 30 0.48 0.62 0.89 1.18 2.08 1.62 1.13 0.85 10 0.35 0.52 0.86 1.23 2.85 1.92 1.16 0.81
Vert.
Horis.
% to4
50 50 90
10 . 30 10
0.28 0.38 0.29
0.42 0.52 0.46
0.69 0.79 0.80
0.99 1.08 1.16
3.52 2.64 3.49
2.37 1.94 2.19
1.44 1.27 1.25
1.02 0.92 0.86
45 Slope
Down
H to4
50 50 90
10 0.24 0.38 0.65 0.94 4.14 2.65 1.54 1.06 30 0.30 0.43 0.71 1.00 3.36 2.30 1.41 1.00
10 0.25 0.42 0.76 1.12 4.07 2.40 1.32 0.89
Horiz.
Down*
X m 4
50 50 50
20 0.28 0.42 0.69 0.98 3.57 2.38 1.45 1.02 20 0.18 0.31 0.58 0:87 5.56 3.23 1.73 1.15
20 0.11 0.25 0.52 0.81 8.94 4.03 1.92 1.23
H 90 \H 90 4 90
20 0.31 0.48 0.82 1.18 3.23 2.08 1.22 0.85 20 0.20 0.37 0.71 1.07 5.00 2.70 1.41 0.93 20 0.13 0.30 0.64 1.01 7.82 3.35 1.56 0.99
Notes: * Spaces of uniform thickness, bounded by moderately smooth surfaces.
* Where ranee of thickness is givea, the given conductance is the average ever the range; extreme values within the range differ therefrom by less ** 10 percent.
* Interpolation, and moderate extrapolation, of eonduetaneo values are permissible lor other values of mean temperature, temperature difference emiasivitjr E.
effective
* Effective emativity of space, B, is given by - - -+-----1 where u and a are the e:
ivitias of the surfaces of tbe air space. (See Section B, above.)
k The conductances of horiaoDtal spaces with beat flow downward are substantially independent of temperature difference.
* Based on Nstiooal Bureau of Standards data presented in Bousfa# Ecsamck Popcr No. 33, Hs-n and Home Finance Agency, 1954 (U. Office, Washington, D. C.).
Government Printing,
Heat Transmission Coefficients of Building Materials
99
Table 4 .... Conductivities (k), Conductances (C), and Resistances (R) of Building and Insulating Materials
(Design Values)* fhem constants ore expressed m Btu per (hour) (square foot) (Fahrenheit degree temperature difference). Conductivities (k) are per rad> thickness and,
condolences (C) ore for thickness or construction stated, not per inch thickness
Material
Description
Density (U> per Cu FI)
Conductivity or
Redstone* (R)
Per inch
For
G) G)W (C) thickness Bsfed
AIR SPACES*
See Table 1--Section B
Position
Heat Flow
Horizontal.............Up (winter).............................
Horizontal....... Up (summer)........................
Horizontal............ Down (winter)......................
Horizontal............ Down (winter)......................
Horizontal............ .Down' (winter)......................
Horizontal............ Down (winter).....................
Horizontal............ Down (summer)..................
Horizontal............ Down (summer)..................
Horizontal;.......... Down (summer)..................
Sloping, 45..........Up (winter)............... ..........
Sloping, 45.........Down (summer)..................
Vertical..................Horiz. (winter)....................
Vertical.................. Horiz. (summer).................
Thickness ------ %-A in. x-*TM.
..........1H in. ...............4 in.
............ H in.......... 1M in. ...............4 in. ....H-A in. --K-4 n.
. . Yk-A in.
1.18 1.28 0.98 0.87 0.81 0.80 1.18 1.07 1.01 1.11 1.12 1.03 1.16
--
AIR SURFACES* Still Aih
15 hph Wind 7> mph Wind :
See Table 1--Section A
Position
Heat Flow
Horizontal.................................................................... ....................Up
Up Sloping (45)....................................................... ....................Up
Vertical...........................................................................
Sloping(45e)..................................................................
Horizontal..................... ................................ ............ .............Down
Any position--any direction (for winter).
Aoy position--any direction (for summer)
BUILDING BOARD*
Boabds,
Panels,
Sheathing, Etc.
BUILDING PAPER
Asbestos-cement board............................................................... Asbestos-cement board.................................................................. %in. Gypsum or plaster board............................................................. %in.
Plywood...............................................................................................
Plywood..................................................................................................in.
Plywood..................................................................................................in.
Plywood.........................
H in-
Plywood or wood panels............................................................ %in.
Wood fiber board, laminated or homogeneous......... ... j
Wood fiber--hardboard type............................................................ Wood fiber--bardboard type.......................................................Kin. Wood--fir or pine sheathing...................................................s$ilin.
Wood--fir'or pine.................................................................... 1H *n.
120
50 50 34 34 34 34
26 31 65 65
Vapor--permeable felt.......................................... Vapor--seal, 2 layers of mopped 15 lb felt Vapor--seal, plastic film.....................................
_ -- ~~
FLOORING MATERIALS
Carpet and fibrous pad........................................ Carpet and rubber pad........................................
Felt, flooring..........-.................................................
Plywood subfloor..................................................... Rubber or plastic tile...........................................
......... inWood, hardwood finish....................................... ..............H in.
120 -- -- --
25 --
-- - --
80 --
no -- --
.
--
INSULATING MATERIALS
0.S-2.0 Mineral wool, fibrous form, processed from rock, slag, or
Wood fiber*.................................................................. Wood fiber, multilayer, stitched expanding".......................
3.2-3.6 1.5-2.0
4.0
0.80
0.42 0.50 1.40
_ -- --
_ -- -- -- 0.45 -- -- -- -- -- -- -- -- .-- 0.28
0.27 0.25 0.27
1.63 1.60 1.46 1.32 1.08 6.00 4.00
33. 3.10 :2.25
3.20 2.12" 1.60 1.07
5.60 1.02 0.49
16.70 8.35
--
24.80 0.48 0.81
-- 3.60 16.70 20.00 12.00 1.28 42.40 12.50 1.02 1.47
--
-- --
0.25
1.25
2.38 2.00 0.72
-- -- -- _ -- -- -- 2.22 -- -- -- -- -- -- -- -- --
3.85
3.70 4.00 3.70
0.85 0.78 1.02 1.15 1.23 1.25 0.85 0.93 0.99 0.90 0.89 0.97 0.86
0.61 0.62 0.68 0.76 0.92 0.17 0.25
0.03 0.32
0.45
0.31 0.47 0.63 0.94
*
0.18 0.98 2.03
0.06
Negl
0.04 2.08 1.23
-- 0.28 0.06
0.08 0.78
0.98 0.68
--
--