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Protect A1 Roofing Underlay 1 x 45m

Product Code: 31795

Impermeable roofing underlay offering major benefits over traditional bitumen and reinforced plastic felts. Twin-ply construction of polypropylene non-woven spunbound layer and PP film. Unaffected by temperature change. Absorbent undersurface prevents condensation drip-off. Lightweight, easy to cut and install. Can be used in all pitched roof constructions, whether insulation is at ceiling joist or rafter level or as a temporary cover for up to 3 months. BRE and Wimlas certified.

  • Weight: 145g/m²
  • Non-Permeable ‘3rd Generation’ Underlay
  • Suitable for all Pitched Roof Constructions
  • Waterproof & Wind-Tight
  • View more information



QtyPrice per item
1 - 2 £39.99
3 + £35.99

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Rated 5 out of 5 by Excellent weather protector Easy to use, gives good weather protection and excellent value for money. 11 Sep 2015
Rated 5 out of 5 by Great Item I used this product to waterproof my summer house walls prior to installing insulation. It has provided a barrier between the wooden walls and the insulation to keep the inside completely dry. It rained shortly after I installed it and the inside was bone dry - maybe another use for this versatile product! 1 Sep 2015
Rated 4 out of 5 by Pleased with product Good product. My roofer was delighted when I bought it as he had used it before. Good price as well! I could only give 3 stars for reliability as it has just been installed. Ask me again in 20 years. 4 Aug 2015
Rated 5 out of 5 by Protect A1 Roofing Underlay 1 Bought this to do a small repair on my porch it was that easy to use I ended up doing the whole porch roof, A1 is the right name for this product, if it holds up as good as it was to use you will never hear any complaints from me.billm 9 Jul 2015
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A1 roofing underlay

My builder has discovered that rain water penetrates underlay when underlay is in direct contact with another surface be it overlapped underlay or rafter or any wooden surface.
Writing is right way up etc so its not upside down !
Can anyone expain please ?
8 Dec 2015
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South Wales
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, Electrician
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Pack Size 1
Product Length 45 m
Product Type Protect A1 Roofing Underlay
Product Width 1 m
Total Product Weight 6.901 kg