ENERGY EFFICIENCY OF A DESIGNED SINGLE-APARTMENT RESIDENTIAL BUILDING

Abstract

coefficient, resistance, heat, temperature, modernization, energy, efficiency, wall, building

The objective of this study is to analyze the energy efficiency of a two-story, single-family, wood-frame residential building in the Lviv region. To this end, we analyzed the energy requirements associated with transmission and ventilation heat losses, assessed their contribution to energy efficiency, and proposed thermal modernization measures.

For simplicity, we determine the average heat loss during the heating season. We assume energy consumption equals energy requirements, and the latter is defined as the sum of transmission and ventilation heat losses. In accordance with standards, the indoor temperature is assumed to be 20°C, and the outdoor temperature is assumed to be equal to the average temperature during the heating season (0.4°C). The duration of the heating season is assumed to be 179 days.

To determine the reduced thermal resistance of the exterior walls, we model wall sections using the finite element method. Since there is a ventilation gap between the exterior finish and the insulation, this structure is not considered in the thermal calculation. Its effect is accounted for through the heat transfer coefficient. We also do not consider interior finishing layers. Based on AIVC data, we adopt an air exchange rate of 0.4 h^-1.

As a result of the analysis of the results obtained, the following conclusions were made. Without taking into account the reduction in heat transfer resistance through thermal bridges, the building meets the regulatory requirements in force at the time of design. Taking into account thermal bridges, the building does not meet the regulatory requirements of that time for some structures, in particular, the resistance for walls is 83% of the regulatory value, and for the attic floor - 86%. To ensure the energy efficiency of low-rise residential buildings with a wooden frame, it is necessary to use cross-insulation of enclosing structures. To increase the energy efficiency of the designed building, first of all, it is advisable to increase the heat transfer resistance of walls and windows. The use of ventilation with recuperation is effective for reducing energy consumption.

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