Saving energy is one of the most important challenges of today's world. The building sector is significant in consumption of energy. In Iran, about 40% of total energy consumption belongs to the building sector accounts. Exterior Glazing of buildings (wall, window … ) that plays a major role in the rate of heat losses. if the glazing are properly considered Heat losses comes down and as a result, energy consumption will be less. In this paper, four types of walls(with the same Internal and external coating) that used in buildings of major cities in Iran are studied and heat losses of walls compared together and it is shown which wall have less heat losses and reduce energy consumption effectively.