Visqueen High Performance Vapour Barrier is an air and vapour control layer (AVCL) and is used in high condensation risk buildings to reduce the risk of interstitial condensation occurring within the structure as well as improving the airtightness of the building.

The barrier restricts the passage of warm, moist air from within the building from permeating into the floor, wall or roof structure.

The barrier is designed to be installed to the warm side of floors, walls and roofs. It is suitable for all BS 5250:2021 humidity classes including those with high internal humidities e.g. laundries and swimming pools.

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• Approvals and Standards
• System Components
• Preparation
• Installation
• Usable Temperature Range
• Additional Information

Approvals and Standards

• Air leakage to BS EN 1026:2016
• CE UKCA UKNI Mark EN 13984:2013
• Quality Management System ISO 9001:2015
• Occupational Health and Safety System ISO 45001:2018
• Environmental Management System ISO 14001:2015

System Components

• VisqueenPro Double Sided Vapour Tape, 20mm x 50m
• VisqueenPro Single Sided Vapour Tape, 75mm x 15m
• VisqueenPro Single Sided Vapour Edge Tape, 150mm x 15m

Preparation

Ensure surfaces are smooth, clean and dust free. When bonding the barrier to the substrate, e.g. timber or metal stubs, the surface should be dry.

The barrier can be cut with a sharp retractable safety knife or robust scissors.

Installation

Visqueen High Performance Vapour Barrier should be installed in accordance with the recommendations of BS 5250:2021 Management of moisture in buildings - code of practice. The barrier should be installed on the warm side of the insulated structure, with care being taken to ensure that all laps, penetrations and abutments are sealed. The membrane should be continuous in order to ensure optimum vapour control performance.

Where the barrier is to be fixed to timber or metal studs, apply sufficient strips of VisqueenPro Double Sided Vapour Tape to the vertical and horizontal studs, head and sole plates, etc to ensure that the barrier remains in position until the plasterboard or construction board is mechanically fixed in position over the barrier. Progressively peel off the tape release film and apply the barrier ensuring adhesion at the tape locations .e.g. by rollering with a seam roller.

The barrier should be installed with the foil (silver) side facing the warm inside of the building.

All joints in the barrier should be lapped by a minimum of 75mm and sealed with VisqueenPro Single Sided Vapour Tape applied centrally over the lap. To aid formation laps should be made over a solid substrate.

Ensure barrier continuity at the junction of horizontal and vertical substrates. Seal abutments with VisqueenPro Vapour Edge Tape applied centrally over the junction. Failure to suitably connect the barrier to other building elements will severely reduce vapour control performance.

vEnsure the barrier is not damaged in service due to residual heat from light fittings. The barrier should not be subjected to gravity forces (unsupported) such as on the underside of roof decks or the underside of floor structures, and should be suitably mechanically secured to ensure that it remains in position during service.

Visqueen air and vapour control layers (AVCLs) do require permanent mechanical fixing, normally achieved by over-boarding the AVCL with a plasterboard or other construction board.

Usable Temperature Range

It is recommended that Visqueen High Performance Vapour Barrier and all associated system components should not be installed below 0°C.

Additional Information

Care should be taken to prevent the AVCL from becoming punctured, stretched or displaced when installing plasterboard or other construction board over the installed AVCL.