This paper presents a numerical method for describing the transient heat transfer through hollow cement blocks via the employment of finite element technique. The block under consideration is assumed to be of rectangular cross-section and composed of two parts, a solid inside which an enclosure (space) is located. The outer surface of the block is exposed to the solar flux. The temperature distribution inside the block as function of space coordinates and its variation with time are the unknown variables of the problem. This leads to a parial differenial equation in the temperature. Finite element technique is used to obtain the solution of the problem for different boundary conditions. The effect of the presence of the enclosure is investigated by comparing homogeneous and hollow blocks results.