Document g25Ewb0zgdmoJgVDNO9zLe8bG

114 - ' CHAPTER 6 1948 Guide Table 1, Conductances (O for Surfaces and Air Spaces All conductance values expressed in Btu per {hour) {square foot) {Fahrenheit degree temperature difference). . Section A. Surface Conductances for Still Air. * Position of Surface Direction of Heat Flow Surface Emissivity e - 0.83 e = 0.05 Hnrigrintal' -. Horizontal-- Vertical.. ........... ........... .................... Upward Downward 1.95* 1.21 . 1.52* 1.16 0.44 0.74 Section B. Conductance of Vertical Spaces at Various Mean Temperatures^ Mean Conductances op Air Spaces for Various Widths in Inches . Fahr Deg 0.128 . 0.6o0 .0,364 0.493 0.713 i.op 1.500 ; 20 30 ... 40 -- 50 60 70 80 90 100 110 120 130 140 150 : 2.300 2.385 2.470 2.560 2.650 2.730 2.819 2.908 -2.990 3.078 3.167 3.250 3.340 3.425 1.370 1.1S0 . 1.425 ' 1.234 1.480 1.288 1.535 1.340 1.590 1.390 1.648 1.440 1.702 1.492 1.757 1.547 ' 1.813 1.600 1.870 1.650 1.928 1.700 . 1.980 1.750 2.035 1.800 2.090 - . 1.852 1.100 1.148 1.193 1.242 1.295 1.340 1.390 1.433 . 1.486 1.534 1.5801.630 1.680 1.728 1.040 1.080 1;125 1.168 1510 1.250 1-.295 . 1.340 1.380 1.425 1.467 1.510 1.550 1.592 1.030 1.070 1.112 1.152 1.195 1.240 * 1.280 1.320 1.362 1.402 1.445 1.485 1.530 1.569 1.022 1.065 1.105 1.149 1.188 1J228 1.270 1.310 1.350 1592 1.435 1.475 1.519 1.559 . Section C. Conductances and Resistances of Air Spaces Faced on One Surface with Reflective Insulatione Location and . Position of Airspace Direction of Heat' Flow Temp*. XDiff Fahr Deg Winter - Summer ^ Conductance* (C) No. of Air Spaces .1 2 3 Resistance* (r) ' No. of Air Spaces 123 Rafter Space (8 in.) Horizontal Horizontal Down Up 45 45 0.10 0.27 0.07 0.17 10.00 14.29 3.70 5.88 Horizontal Horizontal Down Up 25 .0.09 .0.06 11.11 16.67 25 0.24 0.16 4.17 : 6.25 : 30 deg slope . 30 deg slope. Down Up. 45 - 45 . 0.15 0.25 0.10 0.17 6.67 10.00 4.00 <5.88-. 30-:deg slope . : ' Down . ' 25 0.13 0.09 7.69 . 11.11 30 deg slope ...Up 25 0.23 0.14 4.35 7.14 Stud Space <3M in.) Vertical/ Vertical 30 0.34 2.94 40 0.23 0.13 4.35 .7.69 . Vertical/ Vertical 15 0.32 20 .. 0.18 0.11 3.13 5.56 9.09 Vertical* 30 0.48 2.17 Radiation and Convection from Surfaces in Various Positions, by G. B. Wilkes and C. M. P. Peterson CA.S.H.V.E. Transactions, Vol. 44, 1938. p. 513). 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). Thermal Test Coefficients of Aluminum Insulation for Buildings, by G. B; Wflkes; F: G.Hechler and' E. R. Queer (A.S.H.V.E. Transactions, Vol. 46. 1940). `^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 refiective surface (aluminum); having an emiasivity of .0.05 facing each space and are based on total space between plaster base and sheath ing, 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. __ * Radiation and Convection Across Air Spaces in Frame Construction, byG. B. Wilkes and C. Peterson (A.S.H.V.E. Transactions, Vol. 43, 1937, p. 351). The recommended surface conductance for calculating heat 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 derived from Fig. 3 which was based on tests :conducted at the University of Minnesota, and appiy to vertical surfaces. Heat Transmission Coefficients of Building Materials 115 Table 2. Conductivities (&> and Conductances (Q of Building and Insulating Materials. These constants are expressed in Btu per (hour) {square foot).{Fahrenheit degree temperature difference). Conductivities {k) are per inch thickness and conductances {) are for. thickness or.'consiructton stated, not Per inch thickness. Material Description Dbnsitt (Lb per Mran T*mp Cd Ft) Dbg) CONDUCTIVITT or : Conductsncb (i> 1(0 Resistance \Per Inch Thickness For Thickness Listed (i) (*) < BUILDING BOARDS (Non-Instjiating),,--.. Compressed cement and asbestos sheets-- Corrugated asbestos board--..................... Pressed asbestos mill board-------------------Gypsum board--gypsum between layers ; ofheavy paper..'..............------------------- 5^ in. gypsum board.;.........--....................... in. gypsum board-------- ------------------- --. in- gypsum board................. ..................... 123 20.4 605 .625 53.5 86 110 86 70 90 2.70 0.48 054 1.41' 3.73 2.82 -- 2.60 057 2.08 1.19 0.71 -- - ( ___ (2) - -- (3) (3) 057 055 058 (1) FRAME CONSTRUCTION 1 in. fir sheathing and buildingpaper....... ... COMBINATIONS.... ............. 1 in. fir sheathing, building paper and ; yellow pine lap aiding....... ........................: 1 in. fir sheathing, building paper and t : stucco............. ......................----.....-...... . .... . Pine lap siding and building paper, siding 4 in. wide...........................------............ Yellow pine lap siding......... .......................... -- .30 f 20 __ 20 __ 16 -- 056 --------- 050 ,-- 052 ' -----` 055 158 -- 1.16 (4) 2.00 ( 152'" (4) ' 1.18; i (4). 0.78. . (4) MASONRY MATERIALS Brick-------- ---------------- _ Ciat Tile, Hollow. Concrete Damp or wet.-....................------ ------Common yellow clay brick4........................ One tier yellow common day brick, one tier face brick, approx. 8 in. thick0.......... 5.0* -. 45 . 0.20 0.21 -- -- 0.77 -- (2) -- (4) 150 (4) 2 in. Tile, in. plaster bothsidea................ 120.0 4 in. Tile, $4 in. plaster bothsidea............ 127.0 6 in. Tile, H in- plaster both sides................ 1245 110 100 105 1.00 6.60 0.47 -- i.oo. (2) 1.67 (2> 2d3 . (2) 8 in. Tile, average of 8 types (Walls No. 59,63,64.66.67.90,91,92).................... ____ ..." . 0.52 1 .___ 1.92 (4); 12 in. Clay tile wait: 8 in. x 5 in. x 12 in. and 4 in. x 5 in. x 12 in.*........................... ___ 056 ------ 354 { (4) 1155- 0.09 ___ Sand and gravel aggregate, various ages to i- -to (6) and mixes..__ ------ ------- ~.-------------------Sand and gravel aggregate.--___ --._____ 142 75 1656 12.6 ! r0.06 -- o:o8 . ... (4 Limestone aggregate-_________ _______ 132 - 75 105 0.09 . (4) Cinder aggregate.-------------- --...... 97 75 4.9 ;: 74.6 75 -257 -- 052 0.44 ,...- (4) -- 4) Pumice (Mined in California) aggregate*. Expanded burned day aggregate*--......... Burned clay aggregate*----- ;------ ........ Blast furnace slag aggregate:-----------...-- Expanded vermiculite aggregate--------------Expanded vermiculiteaggregate.------------ 65.0 .59.9 67.1 76.0 20 26.7 .75 2.42 75 2.28 75 -256 70 1.6 90 0.68 00 . 0:76 ' -- 0.41 ___ (4) 0.44 . -- (4) ; 055 __ 4) 0.63 ____ (3) : ,,,, ' 1.47" 3) 152 - -- (3) Authorities: ' .' .* lU.-S. 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 ' manufacturers. F. B. Rowley, et al, tests conducted at the University of Minnesota. A.S.H.V.E. Research Laboratory. E. 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). Heat Transmission Through Insulation a9 Affected by Orientation of Wall, by F. B. Rowley and. ; C. E.Lnnd (A.S.H.V.E. Transactions. Vol. 49. 1943, p. 331). j " eThe Effect of Convection in Ceiling Insulation, by G. B. Wilkes and L. R. Vianey (A.S.H.V.E. Trans- ' ACTIONS, Vol, 49, 1943, p. 196). , JSee A.S.H.V.E. Research Report No. 915--Conductivity of Concrete, by F. C. Houghten and Carl Gutberlet (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 BMS13, U. S. Department of'Commerce, National Bureau of Standards, Washington, D. C. ~ *Roofing, 0.-15 In. thick (1.34 lb per square foot), covered with gravel (0.83 lb per square foot);combined thickness assumed 0.25. ' :