著者

丸山 翔永 森 太郎 大柳 佳紀

出版者

日本建築学会

雑誌

日本建築学会環境系論文集 (ISSN:13480685)

巻号頁・発行日

vol.84, no.764, pp.911-918, 2019 (Released:2019-10-30)

参考文献数

12

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Introduction Recently, highly insulated housings are increasing nationwide. Especially in Hokkaido, the development of wooden high insulated housing has been developed from the early days. The number of those housing supplied to the market was growing after the 1980s. Nowadays, those housings are renovating. It is a good opportunity to observe how various methods have influenced insulation performance and deterioration. The purpose of this research is to give insight into distribution of second-hand housing. We analyzed insulation performance such as Q-value and air-tightness of the housings with entire insulation renovation and the existing housings in Hokkaido.  Methods First, we conducted a questionnaire survey. The target housings are 51 housings (Hoppougata-Jyutaku) built in Asahikawa city, Sapporo city (Kita-ku, Toyohira-ku), Kitahiroshima city in the 1990s. Next, we conducted an inspection of the target housings. The target housings consist of 13 renovated houses (a1-a13) in Sapporo city, Kitahiroshima city, Tomakomai city and 17 existing houses in Sarufutsu town, Shimokawa town, Asahikawa city, Sapporo city and Takasu town (b1-b17).  Summary 1) The most frequent renovation was "painting or replacement the outer wall and roof." Also, there were many answers which conducted "replacement of heating and hot-water supply equipment at the same time." 2) About C-value of renovated housings, the RMSE of C-value was 0.56 cm2/m2 and the average absolute error rate was 43%. The C-value in the inspection, about ten years after renovation, were higher than the values just after renovation in many houses, and the airtightness was somewhat deteriorated. However, in most housings, no significant deterioration of the air-tightness was confirmed even after ten years from the renovation. It was confirmed that the performance can be maintained when wooden houses are adequately insulated and repaired.  About C-value of existing housings, those can be classified into the values under 2.0 that provide sufficient air-tightness compared with new houses and the values over 3.5 that not provide enough air-tightness. There were deteriorations such as moisture problem, dew, and fungi when the air-tightness was not enough. 3) About the Q-value, the average error between calculation values and measurement value was 0.32 W/m2K, and the average reliable section width was 0.36 W/m2K. Also, 36.4% of calculated values were within the reliable section, and few housings were below the calculation values. In the future, it is predicted that more reliable values can be calculated by conducting detailed examination of the heating area. 4) In this report, the housings with entire insulation renovation, the deterioration of insulation performance was hardly confirmed. However, in the case of cold climate areas, there is the possibility of deterioration in partial insulation renovation. Therefore, we will consider the finance system to achieve full insulation renovation, not partial renovation in the future.