LAUSR

Abstract This research determined the carbon dioxide permeabilities of different materials and cellulose-insulated wall structures without a vapour barrier as well as the CO 2 balance of bedroom air. Material tests have indicated that the CO 2 permeabilities of building materials correlate closely with their water vapour permeabilities. Thus, the more permeable the external wall structures are, the bigger their impact on the CO 2 content of indoor air. Yet, higher permeability allows more water vapour to pass through the structures, which make them more at-risk for condensation and mould growth. Some calculations on the CO 2 balance of bedroom air were also made which indicated that the need of ventilation is not reduced by the use of gas permeable structures.