The determining of optimum insulation thickness on building walls by considering solar radiation: Case study of Erzincan province

In this study, the change of the thermal insulation thickness to be applied to the outer walls according to the directions was calculated by taking into account the effect of solar radiation with the Degree-Day method. In the calculations, 10 years of daily insolation data between 2008-2018 for the province of Erzincan, which is in the 4th climate zone according to TS 825 standards, was used. Solar air temperature was estimated for each month in all main directions (East-West-North-South) by using insolation data. Optimum insulation thicknesses and payback periods were calculated using the degree-day method for 2 building materials (pumice and brick), 4 fuels (fueloil, LPG, natural gas and coal) and 3 insulation materials (XPS, EPS and rock wool) in four directions. When the results were evaluated, brick, XPS and natural gas are determined as the most suitable building component, insulation material and fuel type according to the usage conditions and payback period, respectively. The optimum insulation thickness was calculated as 6.6 cm for the most suitable building component, at the reference temperature of 24ºC and ignoring solar radiation case. Considering the solar radiation, it was calculated as 3.9 cm in the south and west direction, 4.1 cm in the east direction and 5.7 cm in the north direction.