Moisture supply Set Point for avoidance of moisture damage in Swedish multifamily houses

From 1950 until 1975 approximately 1.3 million apartments were built in Sweden. Now, a considerable part of these are in need of renovation. This paper is part of an evaluation of a new DCV system developed especially for the renovation of these houses. The DCV automatically regulates the air change rate for each dwelling based on measurements of the indoor air. One of the measured parameters is the moisture supply. Simply put, the ventilation rate increases when the measured moisture supply exceeds the set point based on a PI-controller. In this paper, simulations have been carried out to determine an appropriate set point for the moisture supply for avoidance of moisture damage on biological building materials. A worst case scenario has been considered - and the general maximal set point is recommended to be 3 g/m³.