Air Permeable Breather Membranes
New builds are highly susceptible to roof condensation, especially during the first year of occupation. This is normally caused by high humidity as the ‘wet’ trades (plaster, cement, etc.) properly dry out.
An air permeable membrane allows for a much higher exchange of air within the roof than standard vapour permeable membranes. Unlike normal breather membranes, they are much less likely to be overloaded by high moisture content.
An additional benefit of using or specifying waterproof air permeable membranes is that no further ventilation (tile or ridge vents) is required. This both saves you money in the cost of construction, and improves the aesthetics of the building.
Air Permeable Membranes are accepted for use by the NHBC without the use of additional ventilation.