在經過兩次能源危機之後，全世界開始感受到節約能源的重要性，而建築的相關用電是除了工業用電以外最重要的耗能，建築外殼是建築物直接暴露於外氣而且熱能可內外相互傳透的部分，而建築物的耗能量與建築外殼的熱性能成反比[1]，本論文的「熱性能」是指建築外殼控制建築物因室內外溫差與太陽輻射傳入室內所產生的熱得之能力，因此建築外殼的效果越好將可以降低建築的耗能。本研究以彰化縣芳苑國小的圖書教室和幼稚園教室為基地，使用紅外線熱像儀來測得教室裡不同屋頂的內表面溫度，藉由所測得的溫度來比較不同屋頂的隔熱效果，再藉由多元迴歸分析去了解圖書教室室內環境因素對室內外溫度差的影響。研究結果發現，有【保麗龍】、【花架】、【流動空氣層】與【覆土】的手法來設計建築外殼的屋頂時，應能使屋頂的隔熱效果較好；由迴歸分析的結果來看，在圖書教室的室內環境因素中，【窗戶的開啟】和【屋頂內表面溫度】是會顯著地影響到圖書教室的室內外溫度差；屋頂內表面溫度越高會使室內溫度越高，而適當的開窗將有助於室內外溫度差的降低，使建築消耗能源的量減少。

Because of making a more comfortable and convenient life, human beings have already consumed alarge number of natural resources since the Industrial Revolution. In order to support the quality of life, people need to use more energy than ever. People create more greenhouse gas when they use more energy. That will speed up the climate change. It is important to reduce emissions of carbon dioxide for retarding greenhouse effect. Buildings consume a high proportion of energy for air-conditioner and lights. Building envelope can reduce heat gain of a building, so thermal performance of building envelope is crucial factor for keeping indoor thermal environment comfortable. Because the roof can receive a lot of heat energy from the sun, the roof insulation is an important issue to study. There are two objectives in this study. The first objective of this study is to investigate the thermal performance of classrooms’ roofs in Changhua County Fang Yuan elementary school during winter and summer by using infrared thermography. Infrared thermography is a fast and non-contact method to detect temperature distributions on the surface. According to thermal images of two classrooms with different designs of roof, we discover the roof with passive cooling designs by adopting EPS, trellis, ventilated layer and roof greenery has better thermal performance. The second objective is to evaluate the impact of different indoor conditions (temperature of internal surface of roof, numbers of open window, etc.) on the indoor thermal environment of the library. We analyze the data by using stepwise multiple regression method. According to the result of analysis, we find that “adequate open windows” and “temperature of internal surface of roof” can effect the indoor thermal environment significantly. In summary, the roof insulation and natural ventilation are important to indoor climate.