Reliability of Interior Thermal Insulation as a Retrofit Measure in Historic Wooden Apartment Buildings in Cold Climate

Abstract

The performance of the interior insulation as a retrofit measure in historic wooden building was analysed. The designers' view is that an interior insulation of 50 mm mineral wool with vapour barrier is a safe solution. Probability of failure using mold growth risk as an indicator was calculated using stochastic method. Sensitivity analyses revealed that the existence of the vapour barrier is most influential. In addition, the insulation material layer is of critical significance. Of the boundary conditions the moisture excess has a higher effect than indoor temperature. The calculated probabilities showed high risk. Therefore, the considered insulation solution is an unreliable retrofit measure.