Moisture Conditions in a North Facing Wall with Cellulose Loose Fill Insulation: Constructions with and without Vapor Retarder and Air Leakage

Abstract

This paper presents calculated moisture conditions of a wall exposed to a climate equivalent to the North of Sweden. A north facing timber wall with a brick facade and cellulose loose fill thermal insulation is studied both with and without vapor retarder and air leakage. If the vapor retarder is eliminated from the construction, the moisture levels will increase to unacceptable high values. The con struction becomes sensitive to the choice of facing materials and the indoor moisture supply. Air leakage carrying moist air into the construction leads to unacceptably high values even for moderate indoor moisture supplies.

Keywords

air leakage building systems condensation conduction convec tion diffusion heat transfer modeling moisture vapor barrier.

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