The thermal performance and occupant's behavior of about 1000 detached houses in Tohoku city area and in Sapporo and Futyuu as references were investigated in winter of 1992 by means of questionnaire and liquidcrystal thermometers. Since the same investigation have been conducted in winter of 1982, the change during 10 years in such thermal performance and occupant's behavior of houses was analyzed. The results are shown as follows: 1. It was found that cities of Tohoku area could be divided into 4 groups from the viewpoint of thermal performance and occupant's behavior. Aomori was similar to Sapporo, and these of Tohoku city area become more and more like Sapporo during 10 years. 2. In 10 years ago there were a little difference in performance level of thermal insulation and air-tightness between Tohoku city areas. But the performance of thermal insulation and air-tightness in Aomori and Morioka was improved during 10 years, and it was similar to Sapporo. 3. Average air temperatures in living room and bed room of all houses during heating time after supper were 19.6℃ and 12.8℃. respectively. Average living room is 1.5〜3℃ higher than in 10 years ago.
