Document 2qX70oMkanRV6KjQMqgJ6B1j7

American Society of Heating and Ventilating Engineers Guide, 1932 62 Chapter 3--Heat Transfer Through Materials and Constructions Table 31. Coefficients of Transmission (U) of Pitched Roofs Over Heated Attics Note.--These coefficients are expressed in Btu per hour per square foot per 1 dec fahr difference in temperature between the air on the two sides and are based on an outside wind EXPOSURE OF 15 MILES PER HOUR. The values of U in this Table are basedon Ihefollowinq Internal Conductivities or Conductances which are expressed in B.t.u. per Ur per Sq.Ft. per (*F Asphaltor Composition (2qofinq 6.50 asapplied Asbestos 5hinqles 6.00 asapplied Slate Sbinqles 10.31 per I" Wood (Yellow Pine or Fir) 1.00 pert" Wood Lath 4 Plaster 2.00 asapplied Plasterboard 3.15 perl" Plaster (Gypsum) 2.32 per Rtqid Insulation(fcoardform) Flexible Insulation,, Coricboard CellularGypsum(16.*) 0.33 peri' 0.27 per f 0.30 per I" 0.53 peri" Flaked Gypsum (24'} Dry 0.4& per 1" Typical Construction Roofinq Roof Sheatbmq Plaster Plaster Base TVpe of Caitinq s. Type of Roofmq Insulation No Metal Plaster Wood Riqtd riliqid Il'Cork rcork- _D and Qoof Sbealhinq between Calinq Lath _ board|' LaWi^ taala- Imula- board board Roof Batters and J and? andx tion<V *twi<i and t." and % 2 Plaster Plaster Plaster Piaster Hosier Plaster Plaster AB C D e F G H i None Q483 0.303 0.281 0288 0.212 0.161 0.122 0.102 2 WoodShmqtes i" Flexible b 3 on Wood StApsa I" Flexible b 0.11,5 0.161 0.160 0.134 am o.on 0.071 0.126 a 124 0124 0.107 0.012 0.078 0061 4 3'Cellular c Gypsum 0.112 aiio 0.110 0.017 0085 0.072 0.065 5 3jfc"GFylapkseudm c o.on 0016 0.016 0085 0.076 0066 0.051 (o Mono 0.5I& 0.316 0.301 0.300 0.211 0.164 0.124 0.103 7 Asphalt Shtnqles i Flexible b 8 cr Composition Roofmq on Wood 1' Flexible b 1 Sheatfnnq 31`Cellular c Gypsum 10 3J" Hated = Gypsum 0.163 0.165 0.164 0.(36 0113 0.012 0.080 0.121 0.126 0.126 0.101 0014 0.071 0.070 0.120 o.in 0.117 0.102 0.088 0.076 0.067 0.102 0.101 0.101 0.081 0.071 0.068 a 061 II None 0515 0.315 0300 0218 0218 0.164 0.124 0.103 12 Riqid Asbestos V Flexible b Shmqtes on 13 Wood Sbealhinq 1* Flexible b c14 3|- Cellular Gypsum 15 3|"Haited c Gypsum 0.161 0.164 0164' 0136 0.113 0.012 0.080 0.121 0.126 0126 0101 0.013 0071 0.070 0.111 0.117 o.in 0.102 0088 0.075 0.067 0.102 0.101 a ioo 0.081 0071 0.068 0061 lb None 0.548 0.327 0.311 0,301 0.224 0.167 0.126 0.104 17 State or Tile and Roofinq 16 Felt on Wood 17 dheatVnnq 18 Flexible b |" Flexible b 3i'Cellular c Gypsum 3 1" Flaked, c Gypsum 0.172 0.167 0.167 0.138 0114 0013 0.081 0.131 0.128 0127 0.110 0.015 0.080 0.070 ai2i 0.118 0118 0.103 0-081 0.076 0.067 0.103 0.101 O10I 0010 0.071 0.061 0.062 aBased on 1 in. by 4 in. strips spaced 2 in. " *>Can also be applied to underside of roof rafters with furring strips between. ^Assumed in. thick, based on 2 in. by 4 in. rafters. The coefficient used for cellular gypsum, 0.59 is for 18 lb. weight--weights as low as 12 lb. may be used. 63