INSTRUMENTAL THERMAL ENGINEERING INSPECTION OF BUILDING ENCLOSING STRUCTURES BEFORE MAJOR REPAIRS

Abstract

The analysis of the results of the instrumental thermal engineering survey of 22 multi-apartment residential buildings built of silicate and ceramic bricks or reinforced concrete panels, with a service life of buildings of more than 40–50 years, carried out before major repairs is given. Thermal calculations to determine the savings in energy resources showed an average value of savings in thermal energy after insulation of 28 %. Typical defects of enclosing structures identified during thermal imaging examination are presented and systematized. An external examination by infrared thermography is carried out with a thermal imager, followed by processing of thermograms. The absence of influence of the results of thermal imaging examination on the parameters of the insulation is shown. The results of measurements of resistance to heat transfer are presented. The measurements are made using ten-channel heat flux density and temperature meters. The actual measured heat transfer resistance deviated from the design resistance by an average of 16 per cent to 33 per cent. The heat transfer resistance of the wall before insulation is much less than the value of the heat transfer resistance of the insulation and the final resistance of the multilayer wall structure. The error in determining the thermal resistance of the insulated wall does not affect the required thickness of the insulation. It is concluded that the instrumental examination of the enclosing structures of buildings before a major overhaul seems to be redundant. It is recommended to use a typical thickness of insulation during the overhaul of Soviet-built residential buildings, which for the climatic conditions of the Belgorod Region will be 10 cm of mineral wool insulation.