Abstract
The paper formulates the role of thermal inertia of the building materials in the energy supply of buildings and in solution of the energy efficiency problems. The evolution of construction entails the application of new building materials as well as of glazed surfaces in the envelopes of buildings. An analysis is made of the influence of the thermal resistance of building materials and their heat capacity on the thermal inertia indicators of buildings. An inertia scale of buildings has been developed for the choice of the heat supply capacities of buildings at low outdoor temperatures under extreme conditions of the Latvian climate. The ratio of the ventilation capacities has been analysed in the total heating balance at a low thermal inertia of buildings. The significance of innovative ventilation technologies for raising the energy efficiency has been considered.