Computer-aided assessment of critical details of interior thermal insulation systems for historical masonry

Abstract

Interior thermal insulation systems represent in some cases the only admissible form of wall retrofitting. Having different impact on masonry than commonly used exterior systems, application of interior insulation requires a special treatment that consists in an assessment of hygrothermal performance within a pre-design stage. In this paper, computational modelling is used to make the assessment of wall segment with wooden beam laid in it. The assessment is done for unprotected as well as retrofitted wall and the results are compared. It was revealed that presence of interior thermal insulation system may result in deterioration of hygrothermal performance of the wall as the relative humidity content in a reference year is higher by up to 2.5 % after retrofitting. Such a change may speed up degradation processes due to colonization of the beam, e.g. by fungi. Additional measures should therefore accompany this kind of wall retrofitting, which would improve the hygric performance and prevent creation of suitable conditions for the wall segment degradation.