POWERLON ULTRAPERM® PREMIUM BREATHABLE ROOFING MEMBRANE

Roll size: 1.5m x 50m (75m²)

Powerlon UltraPerm® Premium is a high-performance breathable roofing membrane designed for use as a roof tile underlay in warm non-ventilated and cold ventilated pitched roof constructions. Manufactured as a three-layer composite membrane, it incorporates a micro-porous functional film laminated between two non-woven polypropylene layers, delivering excellent vapour permeability alongside reliable weather protection.

With a water vapour transmission Sd value of 0.02m, UltraPerm Premium allows moisture vapour to escape from the roof build-up while remaining watertight to Class W1, the highest classification for underlays. This makes it particularly well suited to modern, highly insulated roof constructions where moisture management is critical.

The membrane is BBA certified (Certificate No. 13/5037) and fully compliant with BS 5534:2014+A2, giving designers, contractors and building control confidence that it meets current UK regulatory and best-practice requirements for pitched roofing  . It is suitable for use beneath slate and tile coverings and can be installed either fully supported or unsupported, subject to wind zone and batten gauge design in accordance with BS 5534.

UltraPerm Premium offers strong mechanical performance, with high tensile strength, good nail tear resistance and proven durability comparable to traditional roof underlays when installed correctly. It also provides temporary weather protection during construction, resisting wind-driven rain and snow prior to final roof covering installation (exposure should be kept to a minimum)

Supplied in 1.5m x 50m rolls, this format is ideal for efficient coverage on site, reducing lap joints and speeding installation for professional roofing teams.