カテゴリー Ⅲ 日本建築学会計画系論文集第 82 巻第 738 号,2019-2028,2017 年 8 月 J. Archit. Plann., AIJ, Vol. 82 No. 738, 2019-2028, Aug., 2017 DOI http://doi.org/10.3130/aija.82.2019 既設木造公営住宅の現状と継続的利用に向けた維持管理の課題 AN OVERVIEW OF EXISTING WOODEN PUBLIC HOUSES AND CHALLENGES OF PROPER MAINTENANCE AND MANAGEMENT FOR THE CONTINUOUS UTILIZATION * 渡邊史郎 Shiro WATANABE It is increasingly important for local governments, most of which faced financial difficulties, to maintain existing wooden public houses, especially those which were constructed after 1985. This article aims to show overview of existing stocks of wooden public houses and challenges of proper maintenance and management for the continuous utilization. The author described overall characteristics of wooden public houses based on the statistical data. In order to examine how wooden public houses have been maintained actually, the author explored cases of ten municipalities which varied in population, and some of which carried out refurbishment and renovation works for wooden public houses. Based on Long-Life Plans made by each local government and the detailed interviews with the officials, the author shows disincentives to refurbishment and renovation works of wooden public houses in terms of financing and construction methods. Keywords : Public house, Wooden construction, Maintenance and management, Long-Life Plan, Case studies 200 1) 2) 3) 4050 4) HOPE 1980 1) 10 2015 2016 1980 10 2) 1951 3) 20 RC 4) * 国土技術政策総合研究所研究官 博士 ( 工学 ) Researcher, National Institute for Land and Infrastructure Management, Dr. Eng. 2019
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9) 10) 11) 23 15 12) 26 4649 20 40 13)2000 1970 2000 14) 27 15) B 16) 26 5658 ++ 17) 28 2011 45 RC 70 WRC RC1RC2RC3 RC RC 1 RC 3 + 28 1) :,,, pp. 283-284, 2016.8 2) :, pp. 63-64, 2002.8 3) :, 27,, 2015.6 4),, p. 144, 2007.6 2016.9.10 https: //www.mlit.go.jp/pri/shiryou/pdf/ooraru.pdf 5),, p. 116, 2007.6 2016.9.10 https: //www.mlit.go.jp/pri/shiryou/pdf/ooraru.pdf 6), : 70,, p. 74, 2015.11 7), :,,, pp. 12-22, 1976.11 8) : 80,,, pp. 5-8, 1980.5 9) : HOPE,,, pp. 7-10, 1983.6 10) : HOPE,,, pp. 8-17, 1986.7 11) :,,, pp. 6-11, 1984.5 12) :,,, p. 14, 1992.4 13) : 19142006,, p. 363, 2015.9 14) :,, p. 9, 1997.2 15),, : HOPE,, 608, pp. 97-102, 2006.10 16) : HOPE,, 54, p.62000.4 17) :,,, p. 7, 2004.2 18) :,, p. 7, 2013.10 19) : 5,,, pp. 32-37, 1981.10 20) :,,, pp. 40-58, 2012.11 21), :,, 2012.4 22) :,, 63,, pp. 399-411, 2012 23) : 1,,, pp. 1223-1224, 2011.7 24) :,,, pp. 1225-1226, 2011.7 25) :, 2012.6.6,, 2016.10.8 http: //yuryou.jp/index.html 26) :, 2016.8 27) :, 2016.3.29 2016.9.24 http: //www.mlit.go.jp/common/001042520.pdf 28) :, 2016.3 2027
AN OVERVIEW OF EXISTING WOODEN PUBLIC HOUSES AND CHALLENGES OF PROPER MAINTENANCE AND MANAGEMENT FOR THE CONTINUOUS UTILIZATION Shiro WATANABE * * Researcher, National Institute for Land and Infrastructure Management, Dr. Eng. Over two millions of public houses are managed by local governments in Japan, and more than half of the total stock requires updating and improvement because of their physical deterioration and mismatching of current housing standards. Actually, they increasingly implemented renovation projects for existing public houses with financial support from the national government. However, there are little wooden public houses renovated with the governmental support. That s because the overwhelming majority of the public houses was those constructed of reinforced concrete or concrete blocks, and those constructed of wood are likely to be newly built compared to the other types of construction. Given that more wooden public houses will past the statutory durable lifetime (30 years for wooden public houses) in the near future, it is increasingly important for local governments, most of which faced financial difficulties, to maintain existing wooden public houses as community assets. This study aims to show real situation of maintenance and management of wooden public houses and to offer basic knowledge which can contribute to proper management of them. As preliminary research, the author conducted analysis of nationwide statistical data of public houses. The results indicate that stocks of wooden public houses was basically divided into two: those constructed before 1970 and those after 1980. The former was constructed by standardized planning and design for resolution of serious accommodation shortage just after WWII, and the latter was characterized by original design and adoption of traditional construction methods and materials and expected to be a regional symbol of dwelling environment. The results also showed that small municipalities, particularly those managing less than 100 units of public houses, are largely divided into two groups: those at a very high rate of wooden public houses and those with a very low rate. As case research, the author selected ten municipalities, which varies in population from less than 10,000 to more than 800,000, and where most of the wooden public houses were built after 1980. According to analysis of the relevant documents including long-life plans of public houses, which are mandatory documents for application for national governmental support, wooden ones are likely to be planned to be utilized continuously even if they past the statutory durable lifetime. Based on the detailed interviews with the officials at the local governments, most of the municipalities pointed out physical deterioration of wooden public houses, and necessities for any refurbishment and renovation. Out of the refurbishment and renovation works after 2000, (1) external wall refurbishment, (2) roof refurbishment, (3) installment of hot-water supply equipment, (4) maintenance of water supply and drainage and (5) termite extermination were pointed out as particularly costly works. But because of difficulties to secure a sufficient budget, most of these works had to be fully financed by themselves. It was found that the municipalities have difficulty to apply for governmental financial support for refurbishment and renovation works of wooden public houses, and they have to adopt an appropriate refurbishing method to construction methods and materials in existing buildings. To implement refurbishment and renovation works for wooden public houses effectively, they should be appreciated from a viewpoint of life cycle cost, and manuals or guidelines for officials at local governments which describe periodic works and expected costs should be organized. (2016 年 11 月 9 日原稿受理,2017 年 4 月 24 日採用決定 ) 2028