Document MGYnxK0YkQeRxgdEjYZDdV0B9

170 , , CHAPTER 9 1952 Guide Table 1. Conductances (O') fob Surfaces and Air Spaces AU conductance value* expressed in Btu per {hour) {square foot) {Fahrenheit degree temperature difference) > .' Section A. Surface Conductances for Still Alra , ____________ . . Surface Emissivity . of Surface .. of Heat Flow : e - 0.83 c - 0.05 Vertical;:'.:-------------- ........-----------:-- Upward' Downward 1.95 1.21 1.52* ... 1.16. . 0.44' . 0.74 Section B. Conductance of Vertical Spaces at Various Mean Temperaturesb Mean Temp Fahr Deg Conductances of Aik Spaces foe Various Widths in Inches 0.128 0.250 0.364 0.493 0.713 1.00 1.500 20 300 1370 1.180 1.100 ' 1.040 1.030 1.022 30 2.385 1.425 1334 1.148 . 1.080 1.070 1365 40 2.470 1.480 1388 1.193 1.125. . 1.112 : 1.105 50 2.560 1335 1340 1.242 1.168 1.152 1.149 60 2.650' 1390 1390 1.295 1310 1.195 1.188 70 2.730 1.648 1.440 1340 1.250 1340 1328 80 24319 1.702 1.492 1390 1395 1380 1370 90 2.908 1.757 1.547 1.433 1340 1320 1310 100 2.990 1.813 1.600 1.486 1380 1362 1350 110 3.078 1370 1.650 1.534 1.425 1.402 ' 1392 120 3.167 1.928 1.700 1380 1.467 . 1.445 1.435 130 140 31250 3.340 1.980 2.035 1.750 1300 1.630 1.680 1.510 1.550 1.485 . 1330 1.475 1.519 150 3.425 2.090 1352 1.728 1.592 1.569 1359 Section C. Conductances and Resistances of Air Spaces Faced on One Surface with Reflective Insulations Location and Position of Aia Space Direction OF . Heat Flow TempDiff Fahr Dbg Winter Summer Conductance* (O No. of Air Spaces 23 Resistance* - No. of Air Spaces 1 23 Rafter Space (8 in.) Horizontal Horizontal 30 deg slope 30 deg slope S04eg elope Down Up Down Up Dows ' Up Down Up 45 45 45 45 25 25 25 25 0.10 037 0.09 034 0.15 035 0.13 033 0.07 0.17 0.06 0.16 0.10 0.17 0.09 0.14 10.00 3.70 11.11 4.17 6.67 4.00 7.69 .4.36 1439 538 16.67 635 10.00 5.88 11.11 7.14 Stud Space (3H in.) Vertical Vertical Vertical* 80 034 234 40 033 0.13 . 435 _ 739 15 032 3.13 20 0.18 0.11 5.56 9.09 30 0.46 2.17 8 Radiation and Convection from Surfaces in Various Positions, by G. B. Wilkes and C. M. F. Peterson (A.S.H.VJ3. Transactions, Vol. 44, 1938, p. 613. ` 'b 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.VJ3. Transactions, Vol. 35,1929, p. 165). ' e 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). 4 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 ing an emissivity of 0.05 facing each space, and are based on total space between plaster base and sheathing, flooring or roofing. The rafter and stud spaces are divided into equal spaces. / Stud space is lined on plaster base side with loose paper with aluminum on surface facing air space The resistance of the small air space between the plaster 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 for calculating beat losses for-still air for non-reflective surfaces is 1.65 Btu. For a 15 mph wind velocity, the recommended value is 6.0 Btu. These coefficients were de rived from Fig. 4, which was based on tests conducted at the University of Minnesota, and apply to vertical surfaces. Heat Transmission Coefficients of Building Materials 171 Table 2. -Conductivities (ft) and Conductances (C) of Building and : Insulating Materials These constants are expressed in Btu per {hotcr) (square foot) (Fahrenheit degree ternpcrature difference). Conductivities {k) are per inch thickness and conductances.(C) are for thickness or construction stated, not per inch thickness. '' ; '.c Material Description B Conduct D o Q B ivity or Conduct Resistance BB a < ance a. 1 Per' For Inch Thick G) G)S i h 2 *a Thick ness (*> (O ness Listed 0S A uthority BUILDING BOARDS (Non-Inbulating) i......... -. Compressed cement and as bestos sheets........................ Corrugated asbestos board.. Pressed asbestos mill board.. Gypsum board--gypsum between layers of neavy paper..................................... I in. gypsum board............... h in. gypsum board............... t in. gypsum hoard............... 118 119 20.4 110 60.5 86" 62.8 70 63.5 90 FRAME CONSTRUC TION COMBINA TIONS :............ 1 8n. fir aWthing nnH hiiflj. ing paper................ ........... 1 in. fir sheathing, building * paper and yellow pine lap siding..................................... 1 in. fir sheathing, building paper and stucco................ Pine lap siding and building paper, siding 4 in. wide........ YeQow pine tap aiding.......... - 30 20; 20 16 MASONRY,MATERIALS Common yellow clay brick8: One tier yellow common clay bride, one tier face brick, approx. 8 in. thick8: __ __ __ Clay Tils, Hollow........ 2 in. Tile; | in. plaster both sides....................................... 4 in. Tile, ) in. plaster both sides....................................... 6 in. Tile, | in. plaster both sides....................................... 8 in. Tile, average of 8 types (Walls No. 59, 63, 64, 66, 67. 90, 91. 92)................. 12 in: Clay t3e wall: 8 in. x 5 in. x 12' in. and 4 in. x 5 in. x 12 in.8....................... 120.0 110 127.0 100 124.3 105 - . oe- o 4.1 0.48 0.84 1.41 0.86 0.50 0.82 0.85 1.28 __ __ 0.77 1.00 0.60 0.47 0.52 - 0.26 ' i n .ig ss 0.24 2.08 1.19 0.71 - 0.20 0.21 - i\ 0.27 0.35 0.38 (3) 0) 1.16 ) 2.00 1.22 1.18 0.78 (4) (4) 8) __ 1.30 (4) 1.00 f-67 2.13 O) (2) (2) 1.92 (4) 8.84 (4) Authorities; * National Bureau of Standards, tests based on samples submitted by manufacturers: 1 A. C. Willard, L. C. Lichty and L. A. Harding, tests conducted at the University of Illinois. /'' * C. Peebles, tests conducted at Armour Institute of Technology, basedon samples submitted by manufacturers. ^ .......................... F. B.1 Rowley, et al, tests bonducted-at the University of Minnesota. .t * A3.H.V.E. Research Laboratory. 1E. A.-Allcut, 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). n _ Heat Transmission Through Insulation as Affected by Orientation of Wall, by F. B. Rowley and C. Lund (A3.H.V.E. Transactions, Vol. 49, 1943, p. 331). ... * The Effect of Convection in Ceiling Insulation, by G. B. Wilkes and L. R. Vianey (AJ3.H.VJ3. Trans actions, Vol. 49r 1943; p. 196). . See AB.H.V_B. Research Report No. 915--Conductivity of Concrete, by F. C. Houghten and Carl Gutberiet (A.S.H.V.E. Transactions. Vol. 38, 1932, p. 47). . See Heating, Ventilating and Air Conditioning, by Harding and Willard, revised edition, 1932. ,,.` ^ See BMSlS, 17. S. Department of Commerce, National Bureau of Standards, Washington, D. C. .I;Hoofing, 045 in. thick (1.34 lb per square foot), covered with gravel (033 lb per square foot), combined tnicxnesa assumed 0.25.