Influence of wall composition on thermal environment of wooden houses

Abstract

This survey was conducted from 2005 to 2008 regarding the thermal environment of three types of experimental houses—a wood and mud composite wall type (Type WM), a mud wall type (Type M), and an insulated wall type (Type I). To reveal the influence of the wall composition of wooden houses on the indoor thermal environment, each experimental house was constructed on the same site. As a result, under natural indoor air temperatures, the monthly average indoor air temperature level and the time ratio of indoor air temperature surpassing the outdoor air temperature were in the following order: Type I > Type WM > Type M. Type WM exhibited the highest phase shift of air temperature, indicating that the insulation performance and heat capacity affect the phase shift of air temperature. The equalization of indoor air temperature through the suppression of the increase in the indoor air temperature of Type M is likely caused by low insulation performance and large thermal capacity. The time fluctuations in electric consumption by air conditioning and indoor–outdoor air temperature differences of each experimental house over 1 day indicated that a building’s thermal load and the thermal capacity are related.