Study Of Temperature In Wood Parts Of Houses Throughout The United States

Based on data from six houses and one office building, temperatures in walls and roofs can rise appreciably above the air temperature. Maximum values in walls may occasionally exceed 130° F., but the cumulative duration of temperatures of 120° F. or higher was not observed to exceed 32 hours in any one year. Maximum values in roofs can reach 170° F., but cumulative durations of temperatures of 160° F. or higher were not observed to exceed 21 hours, or of 150° F. or higher to exceed 64 hours in any one year. Roof temperatures in a house at Madison, Wis., fell as low as the air temperatures, which were below -10° F. for short periods in winter. Temperatures reached are affected by the orientation and the surface characteristics of the wall or roof as well as by the exterior climate. The study points out the value of ventilation and insulation of roof areas and the value of roof overhang in controlling wall temperatures.