Once the Vysa-Film™ has been installed, and before laying the final floor covering, a layer of Polyester Vapour Barrier (PVB) must be used to cover the whole Vysa-Film™ underfloor heating system. The PVB provides:

1) Additional mechanical protection against damage to the Vysa-Film™ by chaffing as slight movements of the final floor can damage the Vysa-Film™ .

2) Additional supplementary electrical insulation as a requirement of the BS EN 60335-2-96 Approval Certificate.

3) Additional protection against mass spillage of liquid on the finished floor. The joints where adjacent edges of the PVB film meet must be overlapped by a minimum of 100 mm. They should then be covered with waterproof, strong adhesive tape (50mm wide Vysa-Bond™ SAT - order code 2465) along the entire joint length.

You must cover the entire floor with the PVB, even unheated areas.
PVB is available in 1m x 25m rolls which will cover approximately 20m² of floor area when installed.

To install PVB, simply roll out the PVB film, cut to length and overlap adjacent pieces by a minimum of 100mm.

Tape along the entire length of the overlap using Vysa-Bond™ SAT fixing tape (1 roll of PVB will require approximately 25m of Vysa-Bond™ SAT fixing tape).

The Polyester Vapour Barrier (PVB) is required to provide additional supplementary insulation and is a mandatory requirement of the BS EN 60335-2-96 Approval Certificate.

PVB is available as required 1m x number of metres required or a a complete 1m x 25m roll.

Don't forget to order 50mm wide x 25m rolls of Vysa-Bond™ SAT fixing tape.