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Protect Zytec vapour permeable underlay

Protect Zytec is a high performance vapour permeable roof underlay. Its low vapour resistance helps to avoid the risk of harmful condensation whilst at the same time 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 and wide coverage across the UK and Ireland.

Features & benefits

  • Completely water and air tight with >2.0m head of water resistance.
  • Helps to avoid condensation risk in the roofspace.
  • Tough and durable.
  • UV stable and heat resistant.
  • Suitable for use in Zones 1-4 at 345mm batten gauge, without the need for additional sealing tapes.
  • Can be used as temporary roof covering.
  • Resistance to wind pressure – 1519Pa, tested to BS 5534.
  • Fully independently certified by BM TRADA.
  • Highly vapour permeable with a performance better than required in BS 5250.
  • UKCA and CE marked.

Glidevale Protect has created two handy visual guides to help you choose the correct ventilation strategy for your projects. Click below to view…

Roof Covering ‘Impermeable’ – Ventilation guidance according to BS5250

Roof Covering ‘Permeable’ – Ventilation guidance according to BS5250



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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.

Important Notice

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