We proposed formulas to estimate the medical costs from the thermal environment in houses. Using these formulas, we examined the most economical thermal insulation performance, taking into consideration insulation costs, heating and cooling costs, and medical costs. The UA value of a house having this most economical insulation performance is 0.4 to 0.5 W/m2K for a floor-insulation house, and 0.36 to 0.4 W/m2K for a foundation-insulation house. We found that by considering not only heating and cooling costs but also medical costs, the cost recovery period for the improvement in the thermal insulation performance was significantly shortened.

It takes many years to recover the initial investment cost for installing housing insulation through savings from energy reduction (Energy Benefit:EB), since construction cost is very high in Japan. This long payback time is the major barrier to the promotion of well-insulated houses. However, it has been found that if Non-Energy Benefits (NEB) of well insulated houses, such as improvement in personal health, reduction of medical expenses and decline in absences from work are all taken into account, the time required to recover the initial investment cost would change from 29 to 16 years. Therefore recognition of NEB is expected to encourage residents to invest in residential thermal insulation. NEB of well-insulated houses is thus evaluated regarding human health in this study.

In order to save energy consumption for air-conditioning of buildings throughout those lifecycle, thermal performance of insulation materials applied in buildings should be kept in required value. On the other hand, there are many factors of ageing of insulation materials such as ambient temperature, vibration and moisture etc. In the previous paper, main factors of thermal performance change were discussed and several experimental results were shown. This paper examines the influences of moisture on thermal performance of various insulations based on three kinds of experiment. In first experiment, the relationship between equilibrium moisture content and thermal conductivity of fiber insulations is obtained. Second experiment is on the influence of gaseous moisture on fiber insulations and the results show that the dimension change of fiber insulations is small even in very humid condition. Third experiment is on the reversibility of thermal conductivity after the internal dew condensation process and the dry process, and the results show that many insulation materials have reversibility except for several plastic insulation foams.

Thermal performance of insulation materials decreases with the passage of time. Such ageing of insulations should be considered in the design stage of buildings to keep insulation performance within the required one throughout the lifecycle of buildings. Firstly this paper focused various factors that affect performances of insulations. The main factors for fiber insulations are moisture vibration and microbe. The main factor for plastic insulation foams is ambient temperature that accelerates the diffusion of blowing agent. Secondly real performances of sold new insulations and scraped old ones were measured and compared the required value by Japanese standard. Performances of some insulations were lower than standard values and performance change was detected. Finally this paper discussed the influence of vibration on performance for fiber insulations based on the experimental data. The changes of insulation depth and thermal resistances were observed after the vibration test.

There are two points of view for the prevention design of moisture problem in the building insulated envelope. One is the strictly prevention of high moisture condition in the insulated wall cavity. The other one is the permission of short-term high moisture condition, condensation and high moisture content of the wooden material as long as keeping physical durability. If the later standpoint were chosen, the insulated envelope design of every variety for Japan would be possible. Nevertheless, there are no criteria to estimate the damage of physical durability of wood by the biological factors related high moisture condition. In the previous paper, we reported about the concept of the prevention design of moisture problem in the building insulated envelope and the relationships between water content and decay various woods under hygrothermal steady conditions. In this paper, the relationships between water content and decay of various woods under two kinds of hygrothermal transient conditions are shown.

There are two points of view for the prevention design of moisture problem in the building insulated envelope. One is the strictly prevention of high moisture condition in the insulated wall cavity. The other one is the permission of short-term high moisture condition, condensation and high moisture content of the wooden material as long as keeping physical durability. If the later standpoint were chosen, the insulated envelope design of every variety for Japan would be possible. Nevertheless, there are no criteria to estimate the damage of physical durability of wood by the biological factors related high moisture condition. The points of this paper are as follows 1) The importance of estimation damage of woods by the moisture problems is describes. 2) 2 case of hygrothermal steady state experiments were done to get basic acknowledge of woods damage by biological factors considering term, water content, temperature and humidity, physical durability.

We present a heating system with thermal storage using a heat pump which supplies heat to the thermal storage installed in a crawl space of a residential house insulated at the foundation walls. We used latent thermal storage materials. This system can charge heat by using cheap nighttime electricity and discharge the stored heat at daytime. We showed equations to determine the air volumes of the heat pump and the ventilator, and equations to determine the phase transition temperature and the amount of the latent thermal storage materials to keep the room setting temperature. We constructed a computer simulation program of this heating system and confirmed the validity of these equations.

We present a heating system with thermal storage using a heat pump which supplies heat to the thermal storage installed in a crawl space of a residential house insulated at the foundation walls. We used sensible thermal storage materials. This system can charge heat by using cheap nighttime electricity and discharge the stored heat at daytime. It is revealed by experimental studies that thermal behavior of the room is greatly influenced by the heat capacity of the thermal storage. We constructed a computer simulation program of this heating system and showed the ratio of the stored heat for generated heat by the heat pump with the volume of the thermal storage materials. We showed the way to determine the volume of the thermal storage materials and the capacity of the heat pump.

'Crawl-space heating' is a heating system using the crawl space as a duct for heat transport from a heat pump. The purpose of this study is to grasp the convective heat-transfer coefficient at the slab-concrete surface and the floor-under surface, under the condition of crawl-space heating. When the crawl-space heating is operated, the air velocity in the crawl space is generally 0.05-0.20m/s and the heat transfer is caused by both the forced convection and the natural convection. We measure the convective heat-transfer coefficient by the wind tunnel test. It is revealed that the convective heat-transfer coefficient at the slab-concrete surface is about 1.0-4.0W/m 2K and that at the floor-under surface is about 6.0-10.0 W/m 2K.

It is well known that humidity influences cooling load, thermal comfort and durability of buildings and various items in them. Many works on prediction of humidity variation in a room have regarded the humidity as unique in a space. However, it does depend on air movement. This paper describes calculations of minute moisture distributions in a room affected by moisture buffering of porous walls. The air velocity distribution is calculated by CFD using two different turbulence models. Then the heat and vapor transient transport in walls and space is calculated. This shows that moisture distribution is not negligible. The difference between the two turbulence models is also determined.

In this paper, we report the experimental studies which were carried out in an experimental house with thermal insulation for its foundation walls, concerning (a) the indoor thermal environment and (b) the heat flow in the crawl space to the ground and to the floor, under the condition of crawl space heating. The main results which we obtained are as follows: 1. The temperature in the room ranges from 18 to 21℃, and that of the floor surface becomes over 23℃. 2. When a fan is put in operation in order to control a current of air in the crawl space, the flow of the heat towards the floor increases, but that towards the ground also increases out of the warm air blowing out zone. 3. It is suggested that most of the heat to the ground is brought by radiation from the lining of the floor.

We found many houses have condensation in the crawl space in summer. These houses have enough openings on the foundation to ventilate and vapor retarder at the ground surface for the recommend in the building code. The temperature and humidity in the crawl space have great influences to durability of the house. We made clear the annual variations of hygro-thermal environment of the crawl space by the field measurements and numerical analysis. We monitored the temperature and humidity variations of 36 houses in Japan for 2 years. The numerical calculations based on the vertical one dimension heat transfer model represented the monitored results. The results show the houses in Japan normally have condensation in crawl space in summer. The condensation term is from one week to one month. The daily average of crawl space's vapor pressure is nearly equal to that of the outdoors. The difference of 2 years results is so great that we think the main factor is outdoor condition. The thermal resistance of the floor and moisture of the ground do not have great effect on the crawl space humidity.

室内塵中の40℃で育つ好温性カビについて実態調査を行った。地域的違いを調べるために，大阪府と高知県や沖縄県を比較した。好温性カビは，フローリングなど室内環境のあらゆる部分に，一定数常在していた。また，水回りなどとは種類の異なるAspergillus fumigatusなどの好温性カビが多かった。これらのカビは夏でも暑い年により多く，大阪より亜熱帯気候である沖縄に多かった。今後地球温暖化が進行し，気温が上昇し，湿度が上昇すれば，大阪などでもA. fumigatusなどの好温性カビ汚染が増加する可能性がある。

中国の6都市で実施したアンケート調査から，カビや化学物質と子供のアレルギー性疾患との関連性が示唆された。また，南部3都市の方が北部3都市よりもアレルギー性疾患の有症率が高かった。一方，実測調査からは，アレルギー疾患を有するケース群とコントロール群間に空気中のカビや化学物質の濃度差は認められなかった。ただし，南部が北部よりTVOCとPM2.5の濃度が高い結果が得られ，有症率の地域差と整合していた。室内温湿度の結果から，中国の住宅ではこの十年で断熱性は変わらないが，換気回数が減少していることが示唆された。カビ防止の観点から，冬型結露を防ぐための最小熱抵抗を中国の観測気象データに基づいて求めた。

本研究は、ダンプビルの原因となる高湿度環境を解決するための最適設計法・住まい方の提案に資する資料を構築することを目的とする。そのために、住宅のダンプビル問題の実態を全国的規模で把握し、居住環境と居住者の健康状態との関連性を統計的に明らかにした。また、室内の湿度変動を安定させる機能をもった様々な多孔質の建材(調湿建材)等の高湿度環境緩和技術の使用効果について、実測やシミュレーションを用いた評価を行った。

研究成果は以下の二つに集約される。 1.木材の腐朽実験 カナダやドイツの研究所を訪れ、木材の腐朽に関する研究の最先端の状況を調査した。これらの調査結果を踏まえて、木造壁体内の温湿度環境を熱湿気同時移動シミュレーションによって予測し、木材の腐朽に関する実験において想定する温湿度環境とした。こうして設定された温湿度環境の下で、木材の腐朽に関わる長期間の実験を行った。これらの実験においては、定期的な目視観察(カビ、腐朽菌等の発生状況、変色、変形)を行い、重量・寸法変化を測定し、概ね1ヶ月毎に試験体を絶乾させて縦圧縮強度等の物理強度を測定した。 2.木質建材のダメージファンクションの作成 上記の実験結果を整理し、木質建材の腐朽に関する知見をとりまとめた。これらの知見に基づき、木材腐朽に関するダメージファンクションを作成し、最終的な成果とした。この成果によれば、ダメージの程度は木材の耐力低下によって表示され、さらに、耐力低下は腐朽の程度によって表される。また、腐朽の程度は含水率や腐朽菌の菌糸成長相当時間などによって表されるが、これは本研究の大きな成果である。このようなダメージファンクションの提示によって、熱湿気同時移動シミュレーションを行い、木造壁体の温湿度と含水率を予測すれば、それらの一連の結果から木材の腐朽の程度と耐力低下を数値として予測することが可能になった。