Energy efficiency of selected envelopes of historical buildings is assessed. The historical masonry is represented by two types of sandstone walls with different thicknesses, which are retrofitted using internal thermal insulation systems preserving the original look of the external facades. All energy-related calculations are based on the results of hygrothermal analysis of the studied envelopes exposed to dynamic climatic conditions. The comparison of energy balances of non-insulated and retrofitted walls shows that the reduction of energy loss can reach up to 89%, depending on the type of the wall that is analysed. Hydrophobic and hydrophilic mineral wools exhibit the best results not only from the point of view of energy efficiency but also from that of hygric performance.
dynamic simulation, energy balance, interior thermal insulation, mineral wool, retrofitting, sandstone
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