Something in the air…

A new development in air barrier technology makes life easier for roofers.

Air barriers (or vapour control layers as many call them) have become increasingly common, as standards affecting new build have risen and roofing upgrade work has brought greater demand for energy efficiency in older buildings. To achieve high performance in either situation, a well-sealed ceiling is essential.

For this reason and with the increasing popularity of airtightness, the arrival of Wallint® solar – with its new combined reflective air barrier and vapour control layer, couldn’t have come at a more opportune moment for contractors. You can apply it in most roofing situations, so whether you’re working over the ceilings of a loft conversion, or in cold roof specifications it’s ideal. It also gives you the opportunity to win additional work by making walls airtight, even in timber frame buildings.
In conjunction with specialist Klober airtightness tapes and sealants Wallint solar® is ideal for energy-efficient construction.

• Vapour resistance of over 500 MNsg – which far exceeds the British Standards Code of Practice for the design of ceiling airtightness in pitched roofs BS 9250:2007, requiring a minimum performance of 250MNsg)
• Greatly reduces heat loss
• Helps improve U-values
• Prevents large volumes of water vapour entering the roof space during a building’s critical drying out period

If you want to use a non-reflective air barrier you can opt for Wallint 50 instead and use it in exactly the same way. Both products couldn’t be easier to use and if you’re a regular installer of underlays, they won’t give you any problems. At either edge of the roof area you simply need to leave a 150mm overlap to allow the air barrier to be sealed to adjoining walls. To fix to rafters and ceiling joists just use corrosion-resistant roofing staples. Laps are sealed using a tape such as Permo® TR and where pipes pass through the barrier you can make a perfectly airtight seal using a Klober Pipe Sealing Collar with the same tape. For refurbs, lay the barrier vertically, either from ridge to eaves or vice versa, allowing small sections of the roof to be worked on without restricting other trades.

Knowing how to install air barriers and the accessories used with them will make even complex roofing designs simple. With the right VCL (vapour control layer) combined with Klober’s range of airtightness tapes and sealants you have the appropriate products to make airtight roofing solutions.