Document zzQbJ70BbE25kG6MBMLLX8br6

Heating Ventilating Air Conditioning Guide 1939 Table 3. Coefficients of Transmission (U) of Masonry Walls Coefficients ore expressed in Btu per hour per square foot per degree Fahrenkeii difference in temperature between the air on the two sides, and are based on a wind velocity of 15 mph. TYPICAL CONSTRUCTION TYPE OF WALL Thickness or Masonbt (Inches) Wau No. Solid Brick Based on 4-in. hard brick and the remainder common brick. 8 12 16 Hollow Tile Stucco Exterior Finish. The 8-in. and 10-in. tile figures are based on two cells in the direction of flow of heat. The 12-in. tile Is based on three cells in the direction of flow of heat. The 10-in. tile consists of one 10-in. tile and one 6-in. tile each having two cells in the direction of heat flow. 8 10 12 16 Limestone or Sandstone 8 12 16 24 Concrete (Monolithic) These figures may be used with sufficient accuracy for concrete walls with stucco exterior finish. Cinder (Monolithic) Conductivity k = 4.36 Haydite (Monolithic) Conductivity k = 3.96 \ Cinder Blocks Cores filled with dry cinders. 69.7 lb per cu ft. Cores filled with granulated cork, 5.12 lb per cu ft. Cores filled with rock wool. 14.2 lb per cu ft. Based on one air cell in direction of heat flow. Cores filled with granulated cork, 5.24 lb per cu ft. Concrete Blocks Cores filled with granulated cork, 5.14 lb per cu ft. Based on one air cell in direction of heat flow. Haydite Blocks Cores filled with granulated cork, 5.06 lb per cu ft; Haydite Blocks Cores filled with granulated cork, 5.6 lb per cu ft. "Computed from factors marked by * in Table 2. `Based on the actual thickness of 2-in. furring strips. 102 6 10 16 20 6 10. 16 20 6 10 16 20 8 8 8 8 12 12 8 8 12 8 S 12 12 2 3 4 5 6. 7 8 9 10 11 12 13 14 15 10 17 18 19 ; 20 \ 21 22 s 23 ' 24 25 ; 26 27 , 28 ` 20 ; 30 ; 31 32 i 33 ; 34 i 35 36 1 Chapter 5. Heat Transmission Coefficients and Tables interior finish 103