The current methods for calculating cooling loads consider the solar heat gain through the transparent component. The solar heat gain through the opaque components is also significant especially for buildings of different functions which may have bigger opaque surfaces. In this paper a simulation model is provided for the determination of the shading effect of the surrounding buildings on a building in a settlement. In the first phase of the calculation procedure, data for solar radiation calculations were obtained through a method by Ozturk and Kilic, and used for determining correlation coefficients, relying on data for Turkey. In the second phase, the simulation of shaded areas on vertical surfaces of buildings, created by neighbouring buildings, used the shadow components of a vertical pole on a three-dimensional coordinate system. After determination of shaded areas on building facades, incidence of the total solar radiation can be calculated and sol-air temperature obtained by using climatic data and the calculated total solar radiation. Finally, a computer programme was developed to implement the calculation procedure and can be used to evaluate the thermal performance and cooling load of a building by taking into account the shading effect of the sur-rounding buildings. In the absence of computer facilities or where the settlement texture cannot be predicted, tables of the shading factors for the building envelope can be prepared as an output of the process.