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Protect A1® underlay

Protect A1® is a high performance, heavy-duty type HR roofing underlay designed for all cold and warm pitched roofs, developed to overcome the disadvantages of traditional Type 1F, 5U felts and plastic sheet materials and is used in conjunction with high and low level ventilation. Providing a secondary line of defence against wind driven rain and snow, Protect A1® offers unrestricted use for wind uplift.

Features & benefits

  • Proven time saving over Type 1F and 5U felts.
  • Can be used as a temporary roof covering.
  • Completely water and air tight.
  • Excellent nail tear and tensile strength.
  • Has unrestricted wind uplift resistance across the UK and Ireland – Zones 1-5 at 345mm batten gauge, without the need for additional sealing tapes.
  • Easy to cut, clean and light to handle.
  • Can be used in all pitched roof constructions.
  • Resistance to wind pressure – 1732Pa, tested to BS 5534.
  • Absorbent undersurface prevents condensate drop off.
  • Fully independently certified by BM TRADA.
  • UKCA and CE marked.



Range Brochure


Product Brochure


Specification clause






Fixing instruction


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Have a question?

For any questions or queries about our product ranges and the technical support services we can offer, please contact us using the form below.

Glidevale Protect is a division of Building Product Design Ltd.

Other subsidiaries include ventilation systems specialist Passivent and Kingfisher Louvres, manufacturer of aluminium louvres systems.

Important Notice

Please be vigilant of fraud/cyber crime. If you receive an email from our parent company Building Product Design Ltd, please check that the email address from the sender ends in '' and any phone number given is 0161 905 5700.

If you receive any emails ending in '' or '', these are NOT legitimate, and you should contact us as soon as possible at

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