Protect Viking Air LR Air & Vapour Permeable 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.

  • 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 for increased water penetration resistance.
  • Highly vapour permeable, exceeding BS 5250 requirements.
  • Completely watertight with >1.0m head of water resistance.
  • 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.


* 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.

Protect Viking Air is fully independently certified by BM TRADA