The effect of external wall insulation on mold and moisture on the buildings

Abstract

In this study, mold and moisture risk of external walls were investigated based on the six different wall types (block bims 1-2-3-4, hollow brick, and aerated concrete) and three different insulation materials (hemp wool, aerogel blanket, and extruded polystyrene). During the examinations, uninsulated and insulated external walls were taken into account according to moisture and mold growth depending on dew point temperatures. While calculating the optimum insulation thickness for uninsulated wall, degree-day and life cycle total cost methods were used. The natural gas, coal, and electricity were accepted as an energy source for heating and electricity was used for cooling. In the study, Izmir, Balikesir, Ankara, Kayseri, and Erzurum cities were selected to represent five climate zones according to Turkish insulation standard (TS 825). As a result of the calculations, the highest values of optimum insulation thickness were found in hemp wool and hollow brick for the electricity energy sources. It was determined as 0.118 m in Izmir and 0.202 m in Erzurum. For the insulated wall, the lowest indoor humidity value, where mold and moisture formation occur, was determined as 78% for Izmir and 69% for Erzurum.