The general aim of this research is contributed to the energy performance assessment of single storey multiple-skin facade. To cover this aim; multiple skin facade are studied by means of experiments and numerical simulation. In this research a numerical model for multiple-skin facades with mechanical and natural ventilation has been developed. The numerical model is two-dimensional and based on a cell centered volume method (CVM). As an improvement, radiation and convection are treated separately and by this means an innovative method is applied to calculate the view factors and heat transfer coefficients between surfaces and each cavity. Then the developed numerical model is validated using measurements from the vliet test building. However, there is no multiple-skin facade application in Tehran. Thus the model is used to assess the influence of different multiple-skin facade parameters in Tehran's climate conditions to show its effect on heat losses if this technology would be applied. As a consequence of the diversity of results, designer should be aware that multiple-skin facades do not necessarily improve the energy efficiency of their designs. (C) 2013 Elsevier B.V. All rights reserved.