A vapour control layer provides a method of meeting the mandatory requirements for the control of condensation, set out in BS 5250 Code of Practice of condensation in buildings.

FAQ

What is a vapour control layer in a single ply roof system?

A vapour control layer is a membrane installed within the roof build up to prevent warm, moist air from inside a building from reaching colder areas, where it could condense and cause damage such as rot, mould or insulation failure.

Why are vapour control layers important in single ply roofing?

Vapour control layers play a vital role in protecting the roof structure and insulation. By controlling moisture movement, they help preserve the performance and lifespan of the roofing system, especially in buildings with high internal humidity levels.

Do I need a vapour control layer on every flat roof?

Not necessarily. Whether a vapour control layer is needed depends on factors such as building use, internal humidity, insulation type and roof design. For guidance, contact one of our technical advisors to evaluate your project’s specific requirements.

Are Sika vapour control layers compatible with Sika single ply membranes?

Yes, Sika vapour control layers are designed to be fully compatible with both PVC and FPO single ply membranes, ensuring long term performance of the full roofing system.