Impact of the Degree Days of the Heating Period on Economically and Ecologically Optimal Thermal Insulation Thickness

The article proposes methods for determining the optimal thermal insulation thickness for economic and ecological reasons, depending on the number of degree days of the heating period. Life cycle assessment was used for the ecological analysis. Analyses were performed for selected variants typical of Polish conditions. The optimal thermal insulation thickness as well as the amount of economic and ecological benefits depends very much on the condition of the building without thermal insulation, but also on the heat source used and the thermal insulation material to be used. For each variant, the optimal thermal insulation thickness for ecological reasons is much greater than the optimal for economic reasons. Taking into consideration the climatic zone and the associated number of degree days of the heating period, the colder the zone, the greater the optimal insulation thickness, as well as economic and ecological benefits.