Study of innovative thermal models to take thermal mass in buildings into account

Precast concrete industry products allow to implement a large panel of technical solutions in a building and, in consequence, to benefit from different levels of thermal mass. The hourly thermal mass, which has essentially an impacts during temperature consign changes, is not integrated in most thermal simulation tools for building. The study focuses on the integration of the skin effect in the regular model which is used with the latest French thermal regulations (model Th-BCE).

The impact of hourly thermal mass implemented in Th-BCE model is small as regards to thermal comfort or heat needs (variations below 0,4 kWh/(m2.year)). The consideration of heating floors is the only parameter that lead to important variations. In that case, the increase of discomfort and heating needs is as important as the daily thermal mass level of the building is light (from 0,3 kW/(m2.yr) for a average thermal mass level to 1,2 kW/(m2.yr) for a very ligtht thermal mass level).