With the ability to frame structures prevent the propagation of heat through them in a house in the cold and hot seasons remain comfortable thermal conditions. The ability of the enclosing structure to resist heat flow from inside out, is characterized by resistance to heat R0 R0 = 1 / v + Rk + 1 / n, where v – heat transfer coefficient inside surface of the fence (in most cases is assumed to be 8.7 W/m2 C) n – coefficient of heat the outer surface of fencing (in most cases is assumed to be 23 W/m2 C) Rk – thermal resistance construction, which depends on the material thickness () and its thermal conductivity (). This dependence is expressed by the relation: Rk = / m2 * C / W here is expressed in meters, and – a (W / m C) thermal conductivity is a characteristic of insulating material itself, while Rk characterizes insulating properties of the structure of certain thickness. Enclosing structures, usually composed of several materials of different thicknesses. In this case, the resulting thermal resistance is equal to the sum of thermal resistance of individual layers. The required thermal resistance R0 of enclosing parts determined by the conditions energy efficiency and in accordance with the requirements of snip ii *- 3-79 Building Heat Engineering" in the 1998 version for various regions of Russia, depending on their climatic conditions. For example, reduced resistance heat transfer of the exterior walls of the conditions of saving for Moscow and Moscow region is 3.2 m 2 * C / watt. .
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