Document NN83wNXqXbJVoL5MyKOLamO4V

180 CHAPTER. 9 1953 Guide: Table 5. Conductivities (k) and Condutances (C)`Gsed in Calculatino Heat; Transmission Coefficients (/t) in Tables 6 to 19 Thm *" Btu /00`) Vo*TM** temperature difference). Conductivities (I) are per tnei Undents* and conductances (C) are for thickness or W - Conductivityr . , . OR Resistance Conductance .. : Material Description G) G)(*> to Per. Inch Thick ness ForThick ness Listed AIR SPACES Bounded by Ordinary Ma terials ...................................... Bounded byAluminum Foil . Vertical, 3 in. or more in width....... Vertical, 3 in. or more in width....... -' EXTERIOR FINISHES (Frame Walib) Brick Veneer.......................... Stucco (1 in.)............................ Wood Shzngles........................ Yellow Pinb Lap Siding___ 4 in. thick (nominal)............................ ; 12.50 _ 1.10 0.46 2.27 K28 -- 0.08 __ 0.91 2.17 0.44 0.78 INSULATING MATERIALS Aluminum Foil...................... Made from mineral or vegetable fiber Corkboard.............................. Insulating Boabd................... or animal hair, enclosed or open .... 0.27 0.30 0.33 -- H.70 Vermiculitb.......................... Fiber made from rock, slag or glaw ,. 0.27 Expanded................................... 0.48 __ 3.70 2.08 -- __ INTERIOR FINISHES Composition Wallboard___ Gypsum Plaster...................... Gypsum Board (i in.)............ Gypsum Lath (J in.) and Plaster................................. Insulating Board (} in.)___ Insulating Board Lath (4 in.) and Plaster............. Inbulating Board Lath (1 in.) and Plaster............. Metal Lath and Plaster ... Pltwood Cl in.)................... Wood Lath and Plaster. . Plaster thickness assumed 3 in............. 0-50 -- 3.70 2.4 0.66 0.60 0.31 4.40 2.12 2.50 2.00 - _ " 1.67 3.18 0.23 0.40 MASONRY MATERIALS Brick................................ Brick . . .......................... Brick................... Cement Mobtab................. 3 in. Clay Tile (Hollow) .. 4 in. Clay Tile (Hollow) 6 in. Clay Tile (Hollow) 8 in. Clay Tile (Hollow) .. 10 in. Clay Tile (Hollow) 12 in. Clay Tile (Hollow)16 in. Clay Tile (Hollow) Concrete............................. Concrete.............. ...... 3 in. Concrete Blocks '. * 4 in. Concrete Blocks___ 8 in. Concrete Blocks........ 12 in. Concrete Blocks .. 8 in. Concrete Blocks........ 12 in. Concrete Blocks....... 8 in. Concrete Blocks .. . 12 in. Concrete Blocks ... Gypsum Fiber Concrete___ Hollow, cinder Afrpremte........... Hollow, light weight aggregate ........... Hollow, light weight aggregated 874 percent gypsum and 124 percent 3 in. Gypsum Tile................. 4 in. Gypsum Tile ;............. Stucco................................ Tile and Tubhawo ... Stone............................... 2.50 12.00 -- 1.66 12.00 .0.89 1.25 2.30 1.28 1.00 0.64 0.60 0.58 0.40 0.31 1.00 1.00 0.80 0.60 0.50 0.47 0.61 0.46 0.40 0.08 0.60 0 08 0.08 1.1^ 0.78 0.78 1.00 1.00 1.25 1.66 2.00 2.13 . --"--;--;------------;-------------------------------------------------------------------------hni nonsontal air spaces depend on whether the heat flow is upward or downwt but in most cases it is sufficiently accurate to use the same values for horisontal as for vertical air spaces. Expanded slag, burned clay or pumice. He&t Transmission Coefficients of Building Materials TM e rvxir>rrrrrTVTTTES (k) ..nrT/n . irnWC /TTc TTI ^Tier. ccneU.nl.crecrpreeeei in Btu ^ 181 Material Description Conductivity or Conductance ' Resistance G) G)to 3er Inch Thick- . ness For Thick ness Listed roofing materials Asphalt Shingles.................... Built-up Roofing..................... Assumed thickness 1 in.......................... Slate.................................................. Assumed 4 in....................................... . Wood Shingles........................... SHEATHING 10.00 Fir or Yellow Pine (1 in.). Actual thickness 31 in............................. Fir, Plus Building Paper. . Actual thickness 34 in............................. SURFACES Ordinary non-reflective materials, 15 mph Wind Velocity........... Ordinary non-reflective materials, vertical.................................................. - 6.00 6.50 3.53 6.50 20.00 1.28 2.82 0.42 2.56 1.02 0.86 1.65 6.00 WOODS Fir Sheathing (1 in.) Build ing Paper and Yellow 1.15 0.80 Q.50 0.10 0.87 1.25 0.17 0.15 0.28 0.15 0.05 0.78 0.35 2.37 0.39 0.98 1.16 0.61 0.17 2.00 and wall temperatures. The possibility of change in emissivity with time of exposure due to surface coatings, chemical action, deposition of dust, etc., must be considered in selecting a material for use.10 PRACTICAL COEFFICIENTS AND THEIR USE For practical purposes it is necessary to have average coefficients that may be applied to various materials and types or construction without the necessity of making actual tests. In Table 2 coefficients are given for a group of materials which have been selected from tests by various author ities. Since there is some variation in the resulting values due to varia tions in materials and in test conditions, average values for the usual con ditions encountered in building practice have been selected and listed in Table 5. These coefficients were used in the calculation of overall coeffi cients given in Tables 6 to 19. These tables constitute typical examples of combinations frequently used, but any special constructions not given canbe computed by the use of the conductivity or conductance values in Table 2 and the fundamental heat transfer formulas. Caution The user should realize that' the average conductivity and conductance values given in Tables 2 or 5 do not necessarily apply to all products of the same general description. In using these values, judgment should be exer cised with regard to the extent to which the product (either as received or as