Apartments built in Sweden during the record years 1961–1975 with the aim to remedy thehousing shortage and abolish poor standards, were designed for a normal-sized family of 2–4 persons.The mechanical ventilation system, if existing, was primarily designed to ensure an air exchange inthe apartment according to Swedish building regulations. During the last few years, the number ofovercrowded apartments has increased due to housing shortage in general but also due to migration.Another aspect is that the ventilation in many apartments built during the record years is alreadyinsucient at normal occupant load. The question is how doubling or tripling the number ofoccupants and thus, the moisture load will aect the risk of bad air quality and moisture damage.To find out, simulations were made to estimate whether it is possible to obtain sucient air qualityand low risk of moisture damage by only increasing the ventilation rates in existing systems orintroducing new ventilation systems with and without heat recovery and what the consequencewould be in terms of the additional energy demand. Measurements from earlier studies of CO2 andmoisture supply in Swedish apartment buildings were used as input data.
(This article belongs to the Special Issue Energy and Technical Building Systems - Scientific and Technological Advances)