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Protect VP400 Plus LR vapour permeable underlay

Protect VP400 Plus LR is a highly vapour permeable roof underlay. It offers the lowest vapour resistance of any type LR roofing underlay in its class, helping to avoid the risk of harmful condensation, whilst remaining completely airtight. With suitability for use across all pitched cold and warm roofs, the membrane provides a secondary line of defence against wind driven rain and snow, offering a high resistance to wind uplift to BS 5534, ensuring unrestricted use in Zones 1-5 throughout the UK and Ireland.

Features & benefits

  • Completely water and air tight with >7.0m head of water resistance.
  • Strongest underlay in its class & weight range.
  • UV and heat resistant.
  • Tough and durable.
  • Can be used as temporary roof covering.
  • Has unrestricted wind uplift resistance across the UK and Ireland – Zones 1-5 at 345mm batten gauge, without the need for additional sealing tapes.
  • Helps to avoid condensation risk in the roof space in accordance with BS 5250 and NHBC requirements.
  • Resistance to wind pressure – 1676Pa, tested to BS 5534.
  • Fully independently certified by BM TRADA.
  • UKCA and CE marked.



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Fixing instruction


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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.

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