Visqueen Vapour Barrier 2m x 50m

Visqueen Vapour Barrier is a green tinted, semi-transparent polyethylene air and vapour control layer (AVCL) designed to reduce the risk of interstitial condensation within floor, wall and roof constructions in medium condensation risk buildings. By restricting the passage of warm, moist air from within the heated building envelope into the surrounding structure, it protects insulation, framing and finishes from the damaging effects of moisture accumulation over time, while also contributing to the overall airtightness of the building. It is installed on the warm side of the insulated structure — between the insulation and the interior finish — and must be kept continuous across the entire building element, with all laps, penetrations and abutments properly sealed using compatible Visqueen taping products. The semi-transparent green tint allows stud locations to remain visible through the membrane during installation, making it easier to align and fix without lifting the barrier to find the framing beneath. Supplied in a single wound, unfolded 2.0m x 50m roll, the membrane has a thickness of 0.3mm and a water vapour resistance factor (µ) of 550,000, making it highly effective at resisting vapour transmission. It is UKCA, UKNI and CE marked to EN 13984:2013, air leakage tested to BS EN 1026:2016, and should be installed in accordance with BS 5250:2021 Management of Moisture in Buildings. The barrier is mechanically secured by overboarding with plasterboard or construction board, with joints lapped by a minimum of 75mm and sealed with Visqueen FR Single Sided Vapour Tape. Compatible system components include Visqueen FR Double Sided Vapour Tape for bonding to structural components and VisqueenPro Vapour Edge Tape for junctions. Benefits Reduces the risk of interstitial condensation in floor, wall and roof constructions Improves the airtightness of the building — contributes to Part L compliance Semi-transparent green tint — stud locations remain visible through the membrane during installation Single wound roll — no folds or creases that could compromise performance or installation Water vapour resistance factor µ 550,000 — highly effective vapour control Equivalent air layer thickness Sd: 165m Air leakage tested to BS EN 1026:2016 — result: 0 m³/h/m² at ±100 Pa UKCA, UKNI and CE marked to EN 13984:2013 Suitable for use in floors, walls and roofs Manufactured under ISO 9001, ISO 14001 and ISO 45001 certified management systems Good to know Roll size: 2.0m wide x 50m long; thickness: 0.3mm; mass: 270 g/m² Water vapour permeability: 0.22 g/m²/day; water vapour resistance: 825 MNs/g Tensile strength: 20 N/mm² (MD), 19 N/mm² (CD); flexibility at low temperature: -15°C Install on the warm side of the insulated structure in accordance with BS 5250:2021 Lap joints minimum 75mm, sealed with Visqueen FR Single Sided Vapour Tape applied centrally over the lap Bond to structural components using Visqueen FR Double Sided Vapour Tape Seal junctions with VisqueenPro Vapour Edge Tape Do not install below 0°C; protect from puncturing or stretching during overboarding Always refer to the latest Visqueen Vapour Barrier technical datasheet before specification or installation