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Redland Spirtech 400 2S Vapour Permeable Roof Underlay 50m x 1.5m Roll

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Est. Delivery: 100-110 Working Days
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£272.56 Incl. VAT
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Spirtech 400 2S is a high quality, four-layer, vapour permeable underlay for use in pitched roofs. Manufactured from spun bonded polypropylene it is strong, durable and easy to install. Spirtech 400 2S is a new concept for Redland. A heavy-duty underlay with a unique glueing system that allows the horizontal laps to be together to help create a wind-tight membrane with significant resistance to wind uplift.

This is ideal for both warm and hybrid roof systems where wind penetration can affect the performance of the roof insulation at rafter level, as well as traditional cold roofs where the underlay needs to effectively withstand the wind uplift forces acting upon it to ensure it reduces wind loading of the roof tiles.

Length : 50m.
Width : 1.5m.
Roll size : 75m2.
roof pitch :
12.5 to 14.5 degrees : 225mm to 150mm headlap.
15 to 34.5 degrees : 150mm to 100mm headlap.
35 degrees and above : 100mm to 75mm headlap.

When used to create a wind-tight membrane the vertical sidelaps on Spirtech 400 2S need to also be sealed using Redland’s DivoTape or other Redland underlay accessories (see below). DivoTape is a single-sided tape that gives an airtight sealing of laps and junctions. It is a UV resistant PE-foil with mesh reinforcement and is stretchable & easy to tear by hand. It comes in a 60mm wide roll of 25m. When used to achieve sufficient wind uplift resistance for use everywhere in the UK to comply with BS 5534: 2014 underlay requirements it is not necessary to seal or bond together the vertical sidelaps (only the horizontal laps) so long as the vertical laps coincide with a rafter or counterbatten, otherwise they should be sealed or bonded together as for a wind-tight membrane.

Heavy-duty underlay with a unique two strip glueing system for the horizontal laps.
Provides wind tight, sealed roof system for warm and hybrid roofs, improving energy efficiency.
Glue strips suitable for high and low outside temperatures.
Heavyweight underlay with grid reinforcement.
Easy to bond joints.
Outstanding protection against falling objects.
Best in class water-tightness after abrasion.
Achieves sufficient wind uplift resistance for use everywhere in the UK with all tile formats at 450 and 600 mm rafter centres to comply with BS 5534: 2014.

Spirtech 400 2S will be covered by the Redland 15 year SpecMaster guarantee when used as part of a SpecMaster project.
BBA certification is pending for Spirtech 400 2S. 

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