Study on actual environmental conscious and healthy houses fit for climate and living environment in subtropical Okinawa

本研究共分为6个课题，在这3年中进行。第一个主题是关于冲绳亚热带民居热环境的历史变迁。从传统木结构到先进被动冷却系统，选取具有代表性的住宅进行室内气候测量或分析测量数据，考虑室内热条件的变化。二是低纬度地区最大的冷负荷部分——屋顶太阳能保护与隔热。将屋顶花园、瓷砖、RC板和镀锌铁皮屋顶隔热涂料等6种材料设置在真实的屋顶上，并对其热工性能进行了测量。屋顶花园的热工性能最好，其次是瓷砖。该涂料对太阳的保护也得到了证实。第三个主题是关于由冲绳当地材料制成的墙外饰面砂浆的热性能。在一个钢筋混凝土小样板房的西墙和北墙上分别涂上了3种不同类型的完工砂浆。结果表明，即使只是抹灰，也能起到外保温的作用。后3个主题是关于房屋周围的室外环境。第四个主题是传统石材路面的热特性。在Shuri-Kinjo地区保留了由天然石灰石铺设的旧车道，其中一条车道被选为传统人行道。对石质路面与石质路面附近的沥青路面进行了热环境对比测量。无论是白天还是夜间，石料路面的表面温度都低于沥青路面。第五个主题是关于房屋周围的传统树篱。藤本树（Garcinia subelliptina）是冲绳地区抵御咸风的代表树。在Motobu镇Bise地区对老福木树篱进行了详细的调查。调查内容包括老福山树篱的现状和历史变迁。居民们认为福吉树篱对生活环境的影响是好的，但是当房屋从木质改为钢筋混凝土结构时，福吉树篱被砍伐和减少了。最后一个主题是树木，特别是道路树木的热性能。对琉球大学校园内8种树木的热性能差异进行了测量。叶片密度对树冠温度有重要影响。树冠遮阳效果通过天空形状因子进行量化。少

This study consists of 6 topics, and they were carried out in this three years. The first topic is about historical changes of thermal environment in dwelling houses in subtropical Okinawa. Representative 6 houses from traditional wooden structure to advanced passive cooling system were selected to measure the indoor climate or to analyze measured data to consider the change of the indoor thermal conditions. The second topic is solar protection and heat insulation on rooftop that is a largest cooling load part in low latitude zone. 6 materials that include rooftop garden, ceramic tiles and heat insulation paint for RC slab and galvanized iron sheet roof were set on a real rooftop and measured their thermal performances. Thermal performance of rooftop garden is best and followed by ceramic tiles. Solar protection by the paint is also confirmed. The third topic is about thermal performance of finish mortars on the outside of walls that are made from local materials originate in Okinawa. … More 3 types of the finish mortars were plastered on the west and the north wall of an RC small model house. The results show that they can work as outside insulation though they were just plastered. The latter 3 topics are about outdoor environment surrounding houses. The fourth topic is thermal characteristics of a traditional stone pavement. Old lanes paved by natural limestone are left in Shuri-Kinjo area and one of the lanes is selected as a traditional pavement. Comparative measurement of thermal environments on the stone pavement and on asphalt pavement near the stone pavement was conducted. Surface temperature on the stone pavement is lower than that on the asphalt pavement not only in the daytime but in the nighttime. The fifth topic is about traditional arboreal hedges surrounding houses. Fukugi (Garcinia subelliptina) is a representative tree for the hedge against salty wind in Okinawa. Detailed survey on the old Fukugi hedges were done in Bise area of Motobu town. The survey included the present conditions of old Fukugi hedges and historical changes of them. The residents have an opinion that effects of Fukugi hedges on living environment are good, however when the houses changed from wooden material to RC structure, the Fukugi hedges were cut down and reducing now. The last topic is thermal performance of trees, especially roads de trees. The differences of thermal performance between 8 species of trees were measured in the campus of University of the Ryukyus. The density of leaves have major effect on the temperature in the tree crown. Shading effect by tree crown was quantified by the shape factor in the sky. Less