SWIP Vapour Control Layer should be installed in accordance with the recommendations of BS 5250: 2011 ‘Code of practice for control of condensation in buildings’ and should be installed on the warm side of the insulation.
All laps in SWIP Vapour Control Layer and junctions at interfaces with other elements and materials in the building e.g. metal and timber studs and joists, cementitious boards and uPVC window frames should be sealed with an aluminised tape. The layer of the SWIP Vapour Control will be reduced unless it is effectively sealed to other elements of the building.
All joints in the SWIP Vapour Control should be lapped by a minimum of 75mm, and sealed with aluminised tape, which should be applied equidistantly over the lap.
Whenever possible, laps in the SWIP Vapour Control Layer should be coincident with an SWIP Stud in order to aid the sealing process. The number of laps can be kept to a minimum by installing full roll widths of SWIP Vapour Control Layer.
Where the heads of ﬁxings penetrate the SWIP Vapour Control Layer they should be sealed with an aluminised tape, as should any tears, holes or cuts. The tape should overlap the damaged area by a minimum of 75mm. Where larger areas of damage occur they should be repaired with a patch of SWIP Vapour Control Layer and aluminised tape applied as detailed above.