Kelden Construction Ltd. - Produits
PolarFoam
Envoyer une demande de renseignements par e-mail à Kelden Construction Ltd.
Application Details: Spray-Applied Polyurethane Foam insulation (SPF) is widely used in exterior walls, the underside of roof decks and in the overhang areas of buildings due to its excellent insulating characteristics as well as its function to serving as a good air and vapour barrier. The test results provided by a recognized independent testing laboratory exceed the physical properties of CAN/ULC S705.1-01 and indicate that the Demilec closed cell medium density SPF meets the NBC minimum performance levels to serve as thermal insulation, air barrier and vapour retarder when applied at a specific density and thickness, according to the conditions described in the CAN/ULC 5705.2 Standard and the intent of National Building Code. Section 9.19.1.1 of the National Building Code restricts the use of insulation at the underside of the roof sheathing without ventilation as the interior vapours may reach the cold areas past the insulation and cause condensation. However it has not been known as a problem in the case of medium density closed cell polyurethane foam insulation. The SPF foam insulation when applied at certain thickness (50mm and more) provides good air and vapour barrier characteristics_ The Vapour Penneance of Demilec's SPF at 50 mm (core) is 38 ng/Pa*s*m2. Properly detailed and applied foam insulation creates a homogeneous layer, which resists the warm air and vapour movement into the cold areas and thus significantly reduces the possibility of excessive moisture accumulation at the cold areas and condensation. The risk of moisture accumulation is further reduced if the asphalt shingles serve as roofing membrane as the roof shingles allow drying of the roof sheathing. It is therefore our opinion that the use of Demilec's Sprayed in Place Polyurethane foam is an acceptable alternative to the Nation Building Code Section 9.19.1.1. when given the insulation is used only in the areas where asphalt shingles are installed as roofing membrane and no vapour barrier is installed between the insulation and roofing membrane. The application of polyurethane foam insulation to the exterior walls, at the rim joint area, floor projections, attics, underside of roof sheathing and at the inside of concrete foundation wall without polyethylene vapour barrier is acceptable as the foam insulation, when applied at 50mm thickness meets the vapour barrier performance criteria of maximum 60 ng /Pa.s.m2. as setout by National Building Code. The increase in thickness beyond 50nun further increases its resistance to vapour diffusion therefore when applied at a thickness necessary to achieve the required diffusion resistance at these locations, the need of a separate vapour barrier, is eliminated. The application of SPUF is considered even better than 6 mil polyethylene in the rim joist area as it is possible to achieve a layer of the foam vapour barrier well sealed at the perimeters which is hardly possible in the case of polyethylene membrane. which is usually left unsealed at the perimeters between the joists. The polyurethane foam insulation is however combustible therefore it must be covered with a thermal barrier as required by Section 9.10.17.10 or 3.1.5.12 of NBC. A 1/2" gypsum board or a spray-applied fire proofing overlay applied at a thickness and density necessary to achieve the required fire rating can satisfy that requirement.