It is well known that the room air temperature variation of a building originated from the variation of outdoor air temperature, solar radiation and artificial heating or cooling, is greatly influenced by the heat capacity of the building, and its analytical evaluation is very difficult.

There are many attempts to carry out this evaluation, both empirically and theoretically, but most of then are limited to the periodic phenomena.

In this report, a method of calculating the room air temperature variation by means of the weighting function is developed, proposing a theoretical procedure to obtain the weighting functions of buildings, especially of concrete buildings (Chapter 2 and 3).

In chapters 5 and 6 the room air temperature variation for periodic heating and periodic outdoor air temperature variation are discussed using the weighting functions of the building.

In chapter 7 the weighting functions of concrete apartments and one storied concrete tenement houses are calculated. These houses have become very popular in Japan after the war, but owing to their high heat capacity compared with the Japanese traditional wooden houses, they are proposing urgent problems on the room climate design. In the last chapter, the evaluation of the temperature variation of these buildings is carried out using the weighting functions obtained in chapter 7, and it is compared with the measured temperature variation of actual buildings. The good agreement can be found between them, and we can conclude that this method using the weighting function, is useful and practical to evaluate the room air temperature variation.

* manuscript received on February 27, 1962.