The master´s thesis deals with influence of the insulation of the detached house on the costs associated with heating and the effect on the usual price of detached house. In the theoretical part of the thesis are given the basic concepts of heat, the topic of energy intensity of buildings, methods of thermal insulation, types of thermal insulation, the development of thermal properties of burnt brickwork and valuation. In the practical part there are designed variants of economy measures and there are calculations of heat losses of the current state and newly proposed variants. Then follows the energy savings assessment, payback period and the effect on the price of a usual detached house.