Air Open & Vapour Permeable Underlays

Permavent offers the most competitive air open & vapour permeable underlay in the UK. Permavent APEX is a 3 layer underlay for use as a pitched roof underlay. Permanent APEX is a air and vapour permeable underlay providing unique condensation control which eliminates the need for low or high level ventilation. Permavent APEX also provides a secondary barrier to water ingress. All of our underlays are manufactured using the latest technology. All roofing underlays are fully UKCA certified and are rigorously tested to comply with European Harmonised standards. Our roofing underlays are fully tested by BRE.