For roofs needing the highest standard of roof space ventilation, Klober’s Permo® air – classified as an air-open, low resistance underlay – offers an exceptional level of breathability.
In the past, variable performance of vapour permeable underlays led to the NHBC and BSI deciding that only air-open membranes could be used without supporting high level ventilation. Designed to meet this requirement and prevent condensation forming in the roofspace, Klober Permo® air has a water vapour resistance confirmed to be as low as 0.045 MNs/g.
BBA and IAB approved, Permo® air can be used for both cold and warm roof installations, and not only avoids the additional cost of supporting ventilation, but also interruptions in the roofline caused by traditional tile or slate vents. Being manufactured from polypropylene, it is also fully recyclable.