Visqueen A2 Vapour Barrier is used in buildings where an air and vapour control layer (AVCL) is required that achieves a reaction to fire classification A2 - s1, d0 to BS EN 13501-1:2018. The barrier is used 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 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 and is suitable for humidity classes 1, 2, 3, 4 and 5 to BS 5250:2021.

For conformity with the reaction to fire classification, usage of Visqueen FR+ Vapour Tape must not exceed 10% of the area of the Visqueen A2 Vapour Barrier. Contact Visqueen Technical Services for guidance prior to the specification or use of any other tapes with this barrier other than that shown in the system components section of the datasheet.

Care should be taken by the Designer to ensure suitability for applications other than those stated above. Visqueen A2 Vapour Barrier should be approved by all stakeholders prior to use.

Quick Links - Click To Jump To Section:

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

Approvals and Standards

• Achieves a reaction to fire classification A2 - s1, d0 to BS EN 13501-1:2018
• 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

Visqueen FR+ Vapour Tape

Preparation

When fixing the barrier to the substrate, e.g. timber or metal stubs, the surface should be smooth, clean, dry and free from dust or sharp protrusions.

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

Installation

Visqueen A2 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 barrier should be continuous in order to ensure optimum airtightness and vapour control performance.

All joints in the barrier should be lapped by 75mm and sealed with Visqueen FR+ 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 Visqueen FR+ Vapour Tape applied centrally over the junction. Failure to suitably connect the barrier to other building elements will severely reduce airtightness and vapour control performance.

For conformity with the reaction to fire classification, usage of Visqueen FR+ Vapour Tape must not exceed 10% of the area of the Visqueen A2 Vapour Barrier.

Ensure 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 A2 Vapour Barrier and all associated system components should not be installed below 0°C.

Additional Information

Contact our Technical Services on 0113 2455450 (option 2) or send a message to [email protected] for guidance prior to the specification or use of any other tapes with this barrier other than that shown in the system components section of this datasheet.

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.