A mathematical model for predicting the thermal performance of building envelope

As it is well known, in a room, mean radiant temperature, which can be calculated in reference to the room dimensions, room location and the inner surface temperatures of the building envelope and the partitions surrounding the room, is one of the factors affecting bioclimatic users' comfort and even if the indoor air temperature has a constant value, due to the physical properties of the envelope consisting of opaque and transparent components, the inner surface temperatures and mean radiant temperature vary with the rate of heat flow through these components. Therefore the thermal performance of the building envelope should not be analyzed independently from room dimensions, room location and inner surface temperatures. In this study, a new model, which is based on analyzing the thermal performance of the envelope by evaluating the mean radiant temperature in terms of its required value (for thermal comfort), has been developed.