One of the most important functions of a building by human beings is to provide thermally comfortable spaces for the users. Therefore, a great deal of artificial energy is consumed for heating to satisfy thermal requirements in cold zones. In order to satisfy thermal comfort and reduce heating energy consumption at the same time, building parameters affecting indoor climate should be determined properly during the design stage. Building form and building envelope are the most important parameters affecting indoor climate. Building form is an important determinant of total heat loss through the whole building envelope in cold climates. Therefore in this paper, a methodology to determine building form which provides minimum heat loss through the whole building envelope is introduced with its application for Erzurum region that representative city of Turkey for cold climatic zones.