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Protect Viking Air vapour permeable & air open underlay

Protect Viking Air is a new, premium type LR roof underlay offering class-leading performance in air and vapour permeability, for use in warm and cold pitch roofing applications. Fully third party certified, Viking Air helps avoid the risk of harmful condensation in accordance with BS 5250 and NHBC requirements, without the need for additional ventilation as accepted by the NHBC for a cold roof construction.

Designed with superior air permeability at 50 Pascals to BS EN 12114, the underlay also leads its class on wind uplift resistance, meeting Zones 1-4* at 345mm batten gauge to BS 5534, ensuring wide coverage across the UK and Ireland.

Features & benefits

  • Can be used in cold roof construction without additional roofspace ventilation as permitted by NHBC.
  • Superior airflow permeability >78 m³/m²/hr @ 50 Pascals to BS EN 12114.
  • Hydrophobically treated underlay which provides additional water shedding properties.
  • Highly vapour permeable, exceeding BS 5250 requirements.
  • Easily wrapped over ridge rather than cut short, ensuring ventilation and water tightness at construction stage.
  • Tough and durable, yet easy handle with unique grid design for ease of cutting on-site.
  • Fully independently certified by BM TRADA.
  • UKCA and CE marked.

* Meets Zones 1-4 (resistance to wind pressure of 1569 Pa) without need for additional counter batten or integral tape. Achieves unrestricted use for wind uplift (2121 Pa) at Zones 1-5 using 310mm batten gauge or when installed on sarking board.




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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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