Investigating condensation role in defects and moisture problems in historic buildings. Case study Varamin Friday mosque in Iran

摘要

Purpose - The purpose of this paper is to investigate moisture problems and defects which have been caused by condensation in historic buildings. Emphasis has been put on finding condensation possibility on the external walls and inside temperature and humidity. Design/methodology/approach - A third-part study including survey method to identify moisture problems and exhaustion, then determining indoor and outdoor temperature and relative humidity in a two-part survey within four days periods, and finally computer modeling and simulation to finding condensation possibility in the building walls by WUFI and THERM software. Findings - Results indicated that the case study has serious defects and almost 7.5°C differences (Δt) and about 6 percent relative humidity differences (Δh) between indoor and outdoor temperature, and from analyzing computer simulations, condensation risk occurrence between wall layers is witnessed. Also this study shows that some climatic methods applied by traditional architects despite enhancing thermal comfort have caused damages and defects to the building envelope and structure. In this paper, the authors suggest a method to reduce condensation possibility by active ventilation for reducing temperature differences. Originality/value - While there is a lock of technical researches and investigations about architectural heritages conservation, this study tries to perform a technical research and filling the gaps in this subject area.