Impact of thermal modernisation including heat source replacement on the heating load of an existing single-family building in Poland
DOI:
https://doi.org/10.24425/ather.2025.156838Abstract
This study presents a comprehensive analysis of the impact of thermal retrofit, including the heat source modernisation, on the heating load of an existing single-family building located in Szczecin, Poland (Climate Zone I). The building, constructed in 2002, originally lacked thermal insulation in the walls, roof and ceiling, resulting in high operating costs and difficulties in maintaining thermal comfort. The aim of the project was to reduce heat losses, improve energy efficiency and enhance user comfort. The scope of work included thermal insulation of external walls, roof insulation, insulation of the intermediate floor slab and exterior wall section adjacent to the door opening and to the fenestration opening. The analysis conducted using the Audytor OZC 7.0 Edu Pol software showed that the total heat load of the building decreased from 25 710 W to 9476 W, representing a reduction of over 63%. Special attention was given to the analysis of thermal bridges, which are significant sources of energy loss. Using Therm 7.8.77 software, solutions were designed to reduce heat losses in critical areas. The heat transfer coefficients (U-values) for these thermal bridges were significantly reduced – by more than 50% in some cases. As part of the heat source modernisation, the solid fuel boiler and liquefied gas tank were removed and replaced with a condensing gas boiler powered by natural gas from the municipal network. To support the domestic hot water preparation system, flat-plate solar collectors were designed to work in conjunction with the existing dual-coil storage water heater.References
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