Document aJr96De4Km31XL02kj4qn5j3a

284 CHAPTER 12 1957 Guide Notes for Table 8. The inside-outside temperature difference is 70- (-10) or 80 F except where otherwise noted. b Volume of infiltration, cfh = (no. air changes) x (floor or ceiling area) x (ceiling height). e From Equation 5a. d The ceiling heat losses are calculated by estimating the attic temperature and then calculating the loss through the ceiling using the proper temperature difference. This unheated attic is not ventilated during winter months. The attic temperature is estimated from Equation 1 to be 30.2 F when'the outade tem perature is -10 F and room temperature is 70 F. The temperature difference is then 70-30.2 or 39.8 deg. For the insulated residence, attic temperature become 4.6 F and temperature difference 70-4.6 = 65.4 deg. Temperature in garage assumed to be 35 F. 1 Coefficient for wall adjoining garage calculated on basis oi metal lath and plaster on both sides of studs (U = 0.39). One half of value from Table 4, Chapter 11,*for storm windows or weatherstnpping. h Exposed on two sides, weatherstripped windows offset by fire-place. Use U41 Window on one side weatherstripped but double-doors are hard to close tightly. Hence, conservative value of 1)41 Assuming kitchen vent, door to veetibule usually open, allow lull table value of 1H. k One-half value in Table 4, Chapter 11. increased to 1H by. nearby outside door in vestibule. 1 Full value in Table 4, Chapter 11. to allow for frequent opening of outside door. m Two tides exposed, large doors but large volume. Use value 1H as given in Table 4, Chapter 11. " Two small unweatherstripped windows in pro tected location, but fireplace, indicate 1 change. p Heat losses from these rooms into garage are heat gains for garage. Neglect heat loss to basement, as losses from boiler, piping, etc., will probably keep basement near, if not above, 70 F. * Upstairs hall ceiling figures with downstairs. Heat should be provided downstairs for both. Linear feet of exposed edge. BASEMENT PLAN Fig. 2. Floor Plans of Residence Heating Load 285 Table 9. Summary of Heat Losses of Uninsulated Residence (Btu'PerHdur} Room ob Space Walls Ceiling and Roof Floor Glass and. Doob Infil tration Totals > Bedroom A Bedroom B Bedroom C Bedroom D Bathroom 1 Bathroom 2 Living Room Dining Room Kitchen Lavette Entrance Hall Garage Recreation Design Totals Operating Totals* Percentages*1 5520 3620 2650 2740 . 690 1640 7480 3850 .2920 3060 900 * .- .-960*- 840- 34,950 34,950 38.4 7410 5000 3800 3240 1620 1060 ' 2560. -- 1280b 23,410 23,410 25.8 960 320 ... * 1060 570 2,910 2,910 3.2 ' 1440 1440 . 970 720 500 320 1800 3100 950 1100 640 3710 ` 720-. 17.410 17,410 19.1 2180 1470 1260 - 950 630 400 5400 3080 2300 550 1600 1910 2890 . 24.620 12.310 13.5 16,550 : 11,530 8,680 -, 8,610 3.440 ' 3,740' ' 14.680 10.030 6.170 . 4,710 ' 5.700 4.440 5,020 103.300 90.990 100.0 * Wall heat loea of 2180 Btub miuua wall beat gains of 1280. 700 and 1160 Btub. b Heat gains of 960 and 320 Btuh. c Based on H computed infiltration. Based on operating totals. are to have storm sash. The building is constructed as follows (heat transmission coefficients U are parentheses): Walls: Brick veneer, building paper, wood sheathing, studding, metal lath and plaster (0.29). Walls of dormer over garage, same except wood siding in place of brick veneer (0.26). 'Attic Walls: Brick veneer, building paper, wood sheathing on studding (6.42). Basement Walls: 10 in. concrete (0.10). Roof: Asphalt shingles on wood sheathing on rafters (0.44). Ceiling (Second floor): Metal lath and plaster (0.74). Windows: Double-hung wood windows averaging 70 percent glass (0.45; from Chapter 9, Table 18, Section D, the U value for wood windows with storm sash is 0.53 x application factor; by interpolation this factor is 0.85). Steel casement sash in garage and basement (1.13; from Chapter 9, Table 18, U is 1.13 for all glass and the application factor is 1.00). French doors in dining room 50 percent glass, no storm doors (0.85; from Chapter 9, Table 18, U is 1.13 for all glass; by interpolation the application factor is 0.75). Floor (Bedroom D): Maple finish flooring on yellow pine sub-flooring; metal lath and plaster ceiling below (0.26). Floor (Basement and Garage): 4 in. stone concrete on 3 in. cinder concrete (0.10). Solution: The calculations for this problem are given in Table 8, and a summary Table IQ. Summary of Heat Losses of Insulated Residence (Biu Per Hour) Room or Space Walls Ceiling and Roof Floor Glass and Door . Infil tration Totals - Bedroom a Bedroom B Bedroom C y.v!."8 Room fen*00" Lavette HaU 2480 2460- 1440 2180 8,560 1620 1660 1440 1470 6.190 1190 1260 1-70 1260 4.680 1230 1080 690 720 950 4,670 310 540 500 630 1,980 760 250 220 320 400 1,950 3370 1800 5400 10,570 1730 3100 3080 7,910 1320 950 2300 4,570 1390 1100 550 3,040 410 850. 640 1600 3,500 --470* -910** 1060 3710 1910 5,300 840 570 710 2890 5,020 Totals "berating Totals* Percentages*1 16.180 16.180 29.1 7.190 7.190 12.9 2,540 2,540 4.6 17.410 17.410 31.3 24,620 12,310 22.1 67,940 55,630 100.0 Btuh^e'i!16^ k8 ^80 Btuh miuua wall heat gains o1 590, 320 and 540 Btuh. b Heat gains 690 and 220 Baaed on }i computed infiltration. d Based on operating totals.