Document YrjQd1R5DQQBJR2wZMmRwwEvO

* American Society of Heating and Ventilating Engineers Guide, 1930 56 V Chapter 2--Heat Losses from Buildings Table 34. Coefficients of Transmission (U) of Pitched Roofs Over Heated Attics .Xoic --These coefficients are expressed in B.t.u. per hour per square foot per 1 deg. fahr. difference in temperature setoeen the air on the two sides and are based on an outside wind EXPOSURE OF 15 MILES PER HOUR. Thevalues of U in this Table are basedonthefoiWinq Internal Conductivities or Conductances which are expressed in Ext.u. per Ur: per Sq.Ft. per l*F Asphaltor Composition Eoofmq 6. SO asapplied Asbestos Shmqles 4' .0` 0` asapplied Slate Shmqles Wood (Yellow Pine or Fir) Wood. Lath 4 Plaster Plaster board Plaster (Gypsum) Eiqid Insulation(0>oardform) , flexible Insulation, Cork board Cellulor Gqpsum 06*> 10.17 perl' , 1.00 frerf 4.00 asapplied 3.7S peri" 2.32 per f- 0.33 per I* O.CT per I' 0.30 per P 0.53 perP 0.46 per I" Typical Construction Roofinq Roof Sheathinq Plaster Plaster Base Type of Ceiltnq ssu>. ' E d Type of Roofinq and Eoof Sheathinq Insulation between Hoof Rafters Ho Metal Plaster Wood ifctVd fttlqid liCovk remitCalinq Lath , board Lath Insula- bsula- board board andj and? andx -tontf -JMt" and*" andi" Plaster Plotter Plaster Plaster PliKler Plaster Piaster A , e> c D e F G H i Hone Q483' 0.303 0.288 0.288 0.212 0.161 0.122 0.102 z Wood Shmqles t* Flexible b 3 or? Wood Strips 1" Flexible b 0.165 0.161 0.160 0.134 am 0.091 0.078 0.126 0IZ4 0.124 0.107 0.082 0.078 0068 4 3f"Cellular e & Gypsum O.ltZ auo 0.110 0.087 0085 0.072 0.065 5 31**GFvlaokseudm c 0.087 0.086 0.096 0.085 0.076 0.066 0.058 (o Hone 0.518 0.316 0.301 0.300 0.218 0.164 0.124 0.103 7 Asphalt Shmqles Flexible b 8 or Composition Hoofmq on Wood. F Flexible b 3 Sbeatbmq 3f"CGfvtUpsuutmar c 10 31* Flaked e Gypsum 0.168 0.165 0.164 0.136 0.113 0.092 0.080 0.128 0.126 0.126 0.108 0.084 0.078 0.070 o.tzo o.tn o.in 0.101 0.088 0.076 0.067 o.toz 0.101 0.101 0.088 0.079 0.068 a06l II Hone 0.515 0.315 0.300 0.288 0.218 0.164 0.124 0.103 12 Riqid Asbestos VFlexible b 13 Shmqles on Wood Sheathinq F Flexible b 14- 31** CGeypllusluamr e 15 32""GFylapkseumd 4 0.168 0.164 0.164 0.136 0.113 0.082 0.080 0.1Z8 0.126 0.126 0.108 0.093 0.078 0.070 0.118 0.117 0.117 0.102 ao88 0.075 0-067 0.10Z 0.101 0.100 0089 0079 0.068 0.061 ib Hone 0.548 0.327 0.311 0.308 0224 0.147 0.126 0.104 17 State orTile and Hoofmq lb Felt on Wood 17 Sheatbmq 18 ^ Flexible b f Flexible b 3'Ceiiutar c Gypsum 31*GFylapkseudm, e o.nz 0.167 0.167 0.138 a ii4 0.083 0.081 0.131 0.128 0.127 0.110 0.085 0.080 0070 aizt 0.118 0.118 0.103 0-088 0 076 0:067 0.103 aioi aioi 0080 0.078 a 068 0.062 "Based on 1 in. by 4 in. strips spaced 2 in. bCan also be applied to underside of roof rafters with furring strips between. "Assumed 3$4 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 U3ed. 57