ångtättningslager

Ångtätningslager, sometimes translated as vapor barrier or vapor retarder, is a material or membrane used in building construction to prevent or slow the diffusion of water vapor from one side of a building assembly to the other. Its primary function is to control moisture movement within walls, floors, and roofs. In colder climates, the ångtätningslager is typically placed on the warm side of the insulation to prevent warm, moist indoor air from condensing within the colder building structure. In warmer, humid climates, the placement might be reversed to prevent moisture from the exterior from entering the building. Common materials used for ångtätningslager include polyethylene sheeting, kraft paper facing on fiberglass insulation, and certain types of paints. The effectiveness of an ångtätningslager is measured by its vapor permeance, which indicates how easily water vapor can pass through it. A low permeance value signifies a good vapor retarder. Proper installation is crucial to ensure the continuity of the ångtätningslager and prevent gaps or holes where moisture can penetrate. Incorrect placement or installation can lead to condensation issues, mold growth, and degradation of building materials.