Abstract:
This thesis concerns with the development of a computer program for studying the characteristics of heat transfer through roof systems by the heat balance method. Two basic types of system, the gamble and the hip roof systems, are investigated. Each basic roof system is also separated into two cases, those with and without suspended ceiling. The following parameters are considered: the insulation thickness, the use of aluminum foil, the ventilation rate through the roof system, the inclination angle of the roof and roofing materials. Results from the study show that heat transfer from the roof with ceiling to an air-conditioning room is about 40% less than that without ceiling. Ventilation from outside air through the space under the roof system from 10 to 30 ACH correspondingly reduces the heat transfer by 15 to 25%. Installation of 1-inch thick insulation reduces heat transfer about 30 to 40% comparing with a roof with no insulation. The optimum insulation thickness is between 1 to 3 inches and there is no significant decrease of calculated heat transfer when the insulation is thicker that 3 inches. Installation of aluminum foil reduces heat transfer 30 to 40%. Lastly, the roof angle and roofing materials are found to have insignificant effect on the reduction of heat transfer through the roof system.