Proctor Air® is an air- and vapour-permeable, highly water-resistant roofing underlay. Its characteristics allow even very complex pitched roofs to breathe, without the need for air gaps or secondary venting.

The high performance meltblown core at the heart of Proctor Air allows natural air movement to ‘supercharge’ the passage of moisture vapour from the roof space, making the formation of condensation in the roof space virtually impossible.

Key features

Vapour-permeable

Proctor Air has an Sd-value of 0.015m and a vapour resistance of 0.075 MNs/g, making Proctor Air one of the highest performing vapour-permeable membranes on the market. (Vapour permeable underlays are sometimes referred as “breather membranes”)

Fully air-permeable

Air permeable membranes allow air movement through the roof, as well as allowing moisture to escape by diffusion. This means that condensation is far less likely to form on the membrane itself, and also allows the membrane to deal with much higher moisture levels within the building, for example during the drying out period.

Highly water-resistant

Proctor Air is rated W1 under EN13859-1, and has a hydrophobic additive in all 3 layers. The membrane can be left exposed to provide temporary weather protection to the building envelope for up to three months.

More uniform airflow than vents

The air permeability of Proctor Air means a non-ventilated roof fitted with Proctor Air allows a more consistent air flow through the roof than a roof ventilated as per BS 5250, without expensive and time consuming ventilation hardware fitted to the roof.

No VCL required

Installing Proctor Air will mean that a vapour control layer is not required for non-ventilated cold pitched roof constructions.

Warranty

Proctor Air’s 15-year warranty provides peace of mind on any project.