Breathable membrane for unventilated pitched roofs and timber frame walls. Please note this products is completely waterproof and as such can be used as a temporary roof covering. Properties Length: 50m. Width: 1.5m. Roll size: 75m2. Thickness: 0.6mm. Weight: 12kg. Certification: BBA certified. Application Timber frame walls: Kingspan Nilvent can be fixed to a timber frame wall either horizontally or vertically. Slating & tiling: Slating and tiling over Kingspan Nilvent is exactly the same as on any other pitched roof except that, in some instances, the slate / tile battens (if required) are fixed to the previously applied counter“battens. Rooflights: please refer to the instructions provided by the rooflight manufacturer. In the absence of manufacturers information, cut and fit Kingspan nilvent neatly around the rooflight kerb, with an upstand of 50mm. Composition Kingspan nilvent comprises a laminated, 3“layer polyolefin construction. The top layer provides protection from UV and mechanical damage. The middle layer is the functional layer. The bottom layer provides abrasion resistance. Kingspan nilvent has a light grey upper surface, printed with the Kingspan nilvent logo, and a dark grey lower surface. Air permeability Kingspan nilvent is airtight, when tested at normal building pressures, i.e. 50 Pa pressure difference.