Internal Insulation of Masonry Walls with Wooden Floor Beams in Northern Humid Climate

Multi-story buildings in Denmark from 1850–1950 are built with masonry walls and wooden floor beams. Large energy savings can be achieved by insulating the facades. Often interior insulation is the only possibility in order to keep the appearance of the external facade. The internal insulation reduces the drying potential of the wall, which might lead to moisture problems in the beam ends embedded in the masonry due to absorption of driving rain.
This paper describes a solution to avoid the moisture problems and still achieve large energy savings. The thermal analyses are made in thermal simulation programs for two dimensions and three dimensions. The moisture analyses are made by a two-dimensional simulation of the coupled heat, air, and moisture transport.
The results show that leaving an uninsulated part of the wall above and below the floor division could solve the moisture problem depending on the amount of wind-driven rain hitting the facade. The proposed solution would almost halve the heat loss through a typical wall section compared to the original wall structure.