Tempo:
This is common in double-wall construction that maintains a sufficiently warm temperature at the vapour barrier to prevent condensation from vapour diffusion in most Canadian climate zones. Polyethylene film is the most common vapour barrier used in Canadian houses. Other materials serve as vapour barriers such as metal foil, polystyrene insulation, sprayed polyurethane foam, polyisocyanurate insulation, metal and glass. A vapour barrier must be continuous but does not need to be sealed. (An air barrier needs to be continuous and must be sealed). As a result, sheet polyethylene can only serve as both vapour barrier and air barrier if it is sealed to form a continuous airtight assembly around the perimeter of the house.
Basement Floors Dampproofing and air barrier protection against radon leakage into conditioned spaces is usually provided by a sealed polyethylene barrier under the basement slab. This arrangement also constitutes a vapour barrier.
Walls Below Grade Dampproofing on the exterior wall is required to keep moisture out (see “Water Penetration Control: Walls Below Grade” on p. 35). If insulation is located on the exterior (see Figure 15 on p. 49), a vapour barrier is not required. If there is insulation on the interior wall (see Figure 16 on p. 50), an interior dampproofing membrane may be required, if moisture-sensitive materials (for example, framing and batt insulation) are situated close
14 Combined air barrier/vapour barrier staple polyethylene to studs and plate and lap all seams by at least 100 mm (4 in.) 0.15 mm (6 mil) polyethylene plate stud place a bead of acoustical sealant around perimeter and over top of polyethylene at seam ensuring that the sealant is continuous and in line with the stud and plate.
A
B
Basement Floors Dampproofing and air barrier protection against radon leakage into conditioned spaces is usually provided by a sealed polyethylene barrier under the basement slab. This arrangement also constitutes a vapour barrier.
Walls Below Grade Dampproofing on the exterior wall is required to keep moisture out (see “Water Penetration Control: Walls Below Grade” on p. 35). If insulation is located on the exterior (see Figure 15 on p. 49), a vapour barrier is not required. If there is insulation on the interior wall (see Figure 16 on p. 50), an interior dampproofing membrane may be required, if moisture-sensitive materials (for example, framing and batt insulation) are situated close
14 Combined air barrier/vapour barrier staple polyethylene to studs and plate and lap all seams by at least 100 mm (4 in.) 0.15 mm (6 mil) polyethylene plate stud place a bead of acoustical sealant around perimeter and over top of polyethylene at seam ensuring that the sealant is continuous and in line with the stud and plate.
A
B
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