At the time this project was initiated it was noted that considerable attention has been given to the general subject of attic thermal performance, due to the current critical energy situation. The general nature of the system with respect to ventilation, insulation, and performance is fairly well understood in the engineering community. However, the existing design data in the form of effective thermal resistance, total equivalent temperature difference (TETD), cooling load temperature difference (CLTD), and transfer function coefficients are out of date or require verification due to lack of documentation.

A program of research was planned and carried out to generate new design data and to verify some existing data. This involved both experiments with two attics with different radiation heat transfer properties and computer modeling using a response factor model and a transfer function model. Thirteen different commercial roof-ceiling combinations were also investigated with the response factor model.

It was concluded that the response factor model represents the performance of light construction residential and commercial roof-ceiling combinations very well. The transfer function model also simulates roof-ceiling thermal response quite well once the effective resistance of the air space is known.