Permavent APEX is a 3 layer air open and vapour permeable underlay, providing unique condensation control which eliminates the need for low and/or high level roof space ventilation when used in conjunction with air permeable roof coverings. APEX also provides a secondary barrier to water ingress.
Permavent APEX meets the requirements of BS 5534:2014+A2:2018 code of practice for slating and tiling for pitched roofs and BS 5250:2021 Management of moisture in buildings – code of practice.
An integrated double tape system allows APEX to be installed in all UK wind zones.

• Air open and vapour permeable underlay.
• Suitable for use with all types of solar panels.
• BBA certified 23/6867.
• Apex meets underlay recommendations in BS 5534:2014+A2:2018. Slating and tiling for pitched roofs and vertical cladding. Code of practice.
• Integrated double tape system for sealing horizontal laps.
• Apex can be used without low and/or high level roofspace ventilation when used in conjunction with air permeable roof coverings.
• For use in roofing/walling applications where high vapour permeability is required.
• Also available in an untaped version.
• Available in 1m x 50 rolls taped; 0.5m x 50m, 1m x 50m and 1.5m x 50m rolls untaped version