This chapter generally is devoted to dening energy-efcient buildings and the relevant indoor environmental quality; it gives a brief account of rating systems of energy-efcient buildings.

The developing community in its path for rapid development is endeavouring to make all necessary and appropriate measures to enhance the efciency of energy utilisation and to increase the beneciation of the energy resources. Throughout Egypt, energy resources are widely used and consumption rates are in general exceeding the internationally accepted values. The use and application of new and renewable energy sources can be harnessed to design, construct, and to operate a solar building of moderate size for desert applications. This chapter demonstrates the importance of incorporating an energy performance directive as a standard in our region; such a goal will aid energy savings in large buildings and will set regulations for energy-efcient designs that are based on standard calculation methods. The target is to develop standardised tools for the calculation of the energy performance of buildings, with dened system boundaries for the different building categories and for different cooling/heating systems. We endeavour to prepare models for expressing requirements of indoor air quality, thermal comfort in winter (and, when appropriate, in summer), visual comfort and so on with a common procedure for an ‘energy performance certicate’.