This paper discusses the design and construction of a roof integrated solar air heater used in a space heating system for a well insulated house located in Melbourne, Australia. The design of the house and the heat storage system is not discussed and details may be obtained elswhere [1]. The space heating system consists of an array of solar air heaters coupled to a rockbed thermal store located under the floor of the house, such that the rooms are heated by radiation and convection from the floor.