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Protect A1 T3 Plus underlay

Protect A1 T3 Plus is a high performance, heavy-duty type HR roofing underlay designed for all cold and warm pitched roofs, developed to overcome the disadvantages of traditional Type 1F, 5U felts and plastic sheet materials and is used in conjunction with high and low level ventilation.

A new and improved fourth generation of the original A1T3 product, Protect A1 T3 Plus provides a class leading product weight of 190gsm, offering a robust secondary line of defence to the roof, whilst offering customers added value for money.

Glidevale Protect has created two handy visual technical guides to help you choose the correct ventilation strategy for your projects:

Roof Covering ‘Impermeable’ – Download

Roof Covering ‘Permeable’ – Download

Features & Benefits

  • Completely air and water tight, achieving >2.0m hydrostatic head of water resistance.
  • Regularly used for new build and re-roofing schemes.
  • Good nail tear strength and tensile strength.
  • Has unrestricted wind uplift resistance across the UK and Ireland – Zones 1-5 at 345mm batten gauge, without the need for additional sealing tapes.
  • UV and heat resistant.
  • Absorbent undersurface prevents condensate drip-off.
  • Easy to cut and handle, saving time on installation over traditional felts.
  • Does not generate nuisance noise under wind loading.
  • Resistance to wind pressure – 2094Pa, tested to BS 5534.
  • UKCA and CE marked.

Downloads

NBS Specifications

Our products are listed on NBS Source with verified specification details, making it easy for architects and specifiers to add them to their projects. Browse key technical info and application guidance directly from our NBS listings.

BIMstore

Our BIM objects are available on BIMstore, ready to view and download for free. Designed with specifiers in mind, they include key data to support efficient project planning. Browse and download directly from our BIMstore listings.

Frequently Asked Questions

What type of rafter ventilators are available to vent an open eaves?

This depends on what amount of ventilation you require. Our RV625F supplies 25,000mm²/m whereas our RV601F gives 10,000mm²/m.  Our friendly technical advisors can advise the ideal product for your needs.

Are they easy to cut down if they are too wide for the rafters?

Yes, they are made from PVC and can easily be cut with a pair of scissors or Stanley knife.

Where can I purchase Glidevale rafter ventilators?

Either order from your local builders’ merchant or online on the BPD Store.

 Why do I need a fly screen type?

With the ventilator being fitted to an open eaves the fly screen will prevent nesting insects entering the airspace within the loft.

How easy are the ventilators to fit?

The fitting of rafter ventilators is very simple. However, when retrofitting them, there is an element of roofing and brick pointing in order to refit the bottom rows of tiles or slates. For more information, see our handy guide below. Always refer to the supplied fixing instructions when fitting.

Will they fit my roof?

They are available in 400mm, 450mm and 600mm widths and can easily be cut where needed to suit differing rafter centres.

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Have a question?

For any questions or queries about our product ranges and the technical support services we can offer, please contact us using the form below.