A method of calculating the dynamic response of the surface temperature of a building element to changing climatic conditions in Australia is described. The method assumes that all heat flow is one-dimensional and that the building element is composed of a number of homogeneous slabs in good thermal contact. The various heat exchange processes at the surface are discussed and a method for calculating the sol-air temperature is given. Some results of a surface temperature calculation for a brick-clad timber-frame wall are presented. It is suggested that the method will be particularly helpful in the area of assessing materials durability.