The thermal technical condition of building envelopes parts on the example of the regular recurring sections of an exterior wall of a residential building that includes the largest elements amount (windows, monolithic concrete columns, floor slabs endface, lintel, assembly seams) is researched in this paper. The estimation of numerical values of heat flows and temperatures on each parts that are limited of different materials is made and mutual influence of sections from different materials on the thermal technical condition of the parts, that are located near them, is shown. The influence of the section with the local reduction of the insulation thickness on the thermal technical of the located near elements and on the heat losses of the whole researched construction is shown.