Powerlon® VCL 250 & Powerlon® VCL 170 - Vapour Control Layer (AVCL) - Vapour Control Layer

Powerlon® VCL 250 & VCL 170 AVCLs are suitable for all roof and wall applications.

Storage and handling:

• Store the membrane rolls horizontally in a cool, dry, sheltered store.
• Handle the membrane with care and ensure that the membrane is not creased or folded.

Installation:

• Powerlon VCL membranes should be continuous over the whole plan area of the structure. All laps should be sealed with Powerbond® Double Sided Butyl Tape and the number of joints should be kept to a minimum.
• Cold roofs with the VCL membrane draped between purlins, with the insulation above are harder to seal at the laps. In high-risk areas a rigid lining sheet is recommended throughout to support the VCL.
• Warm roofs where the membrane is supported by the structural deck directly beneath is easier to seal. Sealing tape allows for any slight expansion or contraction movement in the decking.
• Service penetrations should be kept to a minimum. Airtight seals are required around each point of entry including soil pipes, vent pipes, roof lights as well as the roof perimeter.
• The VCL should be laid loose, flat and without wrinkles, ensure that the membrane is not creased or folded.
• Cold makes the VCL less supple. Installations should be avoided when temperatures fall below 5℃. Installation in windy conditions is not recommended as the VCL will become difficult to handle and liable to flap in the wind.
• Timber frame fixings should not puncture the barrier.
• Secure to the wall or timber structure with stainless steel staples. Staples and nails should be covered by a second layer of membrane. Pull the membrane tight and always fasten loose ends with staples.
• Joins should only be made where the membrane is supported.
• A continuous double row of Powerbond® Butyl Tape spaced 75 mm apart is recommended for overlap sealing. The overlap should be sealed using Powerbond® Acrylic Tape.
• For optimal water resistance and airtightness, using both methods is recommended.
• All joins should be firmly pressed together using a hand-held pressure roller. Only apply tapes in temperatures over 5℃.
• Prior to covering, the VCL should be thoroughly inspected to verify the integrity of the joining and sealing to ensure that no damage has occurred. Any damage should be repaired to ensure an airtight seal.
• Damaged areas should be repaired using Powerlon VCL. The patch must not extend beyond 150 mm of the damaged area. Fix the patch using a continuous double row of Powerbond® Butyl Tape, spaced 75 mm apart.
• Protect Powerlon® VCLs from UV exposure. Cover and finish the construction of the VCL installation within a maximum of 3 months.

Overlaps:

• Horizontal overlaps should be 150 mm minimum.
• Vertical overlaps should be 150 mm minimum.

See installation instructions for full details.