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Protect A1 Solar

Protect A1 Solar is a high performance, heavy-duty type HR impermeable roofing underlay designed for use on all cold and warm pitched roofs, where in-roof Solar PV Panels are installed.

As the use of in-roof solar photovoltaic (PV) panels on new build dwellings grows, the need for a compatible membrane with appropriate high and low level ventilation is paramount. With solar PV now included in the Standard Assessment Procedure (SAP) for the notional assessment, including PV is widely acknowledged to be the most efficient way to achieve compliance to Part L 2021, helping to lower carbon emissions to hit the 31% reduction target. This also helps housebuilders future proof against the planned requirements of the Future Homes Standard in 2025.

In conjunction with high and low level ventilation, Protect A1 Solar offers a tried and trusted solution to reduce the risk of condensation forming on the underside of solar PV panels. Due to its high resistance to vapour transfer, there is no need for a ventilated counter batten space above the membrane, saving time and material cost.

Features and benefits

  • Helps to avoid condensation forming on the underside of the PV panel reducing the possibility of rotting roof timbers.
  • No need to install additional counter battens above the membrane, reducing time and material costs.
  • Used in conjunction with high and low level ventilation, Protect A1 Solar can help you meet BS 5250 ventilation requirements.
  • Unrestricted use across wind zones 1-5 at 345mm batten gauge covering all of the UK & Ireland in accordance with BS 5534.
  • Completely water and airtight.
  • Excellent nail tear and tensile strength.
  • UV & heat resistant.
  • Absorbent under-surface prevents condensate drip-off.
  • Produced in the UK.
  • BM TRADA independently certified.
  • 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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NBS Specifications

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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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