Hi there,
We would like to say the purpose of breathable roofing felts are the following:
- Provide a means of water vapour to exit the roof. (removing condensation issues) but not exiting.
- Provide a means of keeping wind driven "elements" out.
- Provides a temporary barrier when the tiles/slates are damaged or blown off.
- Provides roof space ventilation.
Whilst breathable underlays are designed to withstand 3 months of UV (which intensity etc is not specified by the BBA) Each day that goes by that it is exposed will, reduce the effectiveness of the product, this should go with ALL breathables.
A quote from our BBA for Ventaflex:
"10 Weathertightness
10.1 Tests indicate that the product will
resist the passage of water and wind-blown
snow and dust into the interior of a building,
2
Standard: B2.2 Selection and use of materials, fittings, and components, and workmanship
Comment: The product complies with these Standards. See section 14
of this Certificate.
Regulation: 17 Resistance to moisture
Standard: G3.1 Resistance to precipitation — Resistance to precipitation
Comment: The product will contribute towards a roof satisfying this
Standard. See sections 10.1 and 10.2 of this Certificate.
3 The Building Regulations (Northern Ireland) 2000
In the opinion of the BBA, Ventaflex Breathable Roof Tile Underlay, if
used in accordance with the provisions of this Certificate, will satisfy or
contribute to satisfying the various Building Regulations as listed below.
Regulation: B2 Fitness of materials and workmanship
Comment: The product is an acceptable material. See section 14 of this
Certificate.
Regulation: C4 Resistance to ground moisture and weather
Comment: The product will contribute towards a roof satisfying this
Regulation. See sections 10.1 and 10.2 of this Certificate.
4 Construction (Design and Management) Regulations 1994 (as amended)
Construction (Design and Management) Regulations (Northern Ireland)
1995 (as amended)
Information in this Certificate may assist the client, planning supervisor,
designer and contractors to address their obligations under these Regulations.
See sections: 5 Description (5.2), 15 Procedure (15.7).
Electronic Copy
under all conditions to be found in a roof
constructed in accordance with the relevant clauses
of BS 5534 : 2003.
10.2 The product resists penetration of liquid
water to a head greater than 3 metres and
consequently may be used as temporary
waterproofing prior to the installation of slates or
tiles. The period of such use should, however, be
kept to a minimum. Advice should be sought from
the Certificate holder."
For the full BBA of this product please visit:
http://www.bbacerts.co.uk/certs/41/4199i1_web.pdf
Roofline Building Products Ltd, is a Trading name of Ventilation Solutions Ltd
For more information or advise please feel free to visit one of our websites:
www.rooflineuk.com
www.vsluk.com
Thanks
Adam King
We would like to say the purpose of breathable roofing felts are the following:
- Provide a means of water vapour to exit the roof. (removing condensation issues) but not exiting.
- Provide a means of keeping wind driven "elements" out.
- Provides a temporary barrier when the tiles/slates are damaged or blown off.
- Provides roof space ventilation.
Whilst breathable underlays are designed to withstand 3 months of UV (which intensity etc is not specified by the BBA) Each day that goes by that it is exposed will, reduce the effectiveness of the product, this should go with ALL breathables.
A quote from our BBA for Ventaflex:
"10 Weathertightness
10.1 Tests indicate that the product will
resist the passage of water and wind-blown
snow and dust into the interior of a building,
2
Standard: B2.2 Selection and use of materials, fittings, and components, and workmanship
Comment: The product complies with these Standards. See section 14
of this Certificate.
Regulation: 17 Resistance to moisture
Standard: G3.1 Resistance to precipitation — Resistance to precipitation
Comment: The product will contribute towards a roof satisfying this
Standard. See sections 10.1 and 10.2 of this Certificate.
3 The Building Regulations (Northern Ireland) 2000
In the opinion of the BBA, Ventaflex Breathable Roof Tile Underlay, if
used in accordance with the provisions of this Certificate, will satisfy or
contribute to satisfying the various Building Regulations as listed below.
Regulation: B2 Fitness of materials and workmanship
Comment: The product is an acceptable material. See section 14 of this
Certificate.
Regulation: C4 Resistance to ground moisture and weather
Comment: The product will contribute towards a roof satisfying this
Regulation. See sections 10.1 and 10.2 of this Certificate.
4 Construction (Design and Management) Regulations 1994 (as amended)
Construction (Design and Management) Regulations (Northern Ireland)
1995 (as amended)
Information in this Certificate may assist the client, planning supervisor,
designer and contractors to address their obligations under these Regulations.
See sections: 5 Description (5.2), 15 Procedure (15.7).
Electronic Copy
under all conditions to be found in a roof
constructed in accordance with the relevant clauses
of BS 5534 : 2003.
10.2 The product resists penetration of liquid
water to a head greater than 3 metres and
consequently may be used as temporary
waterproofing prior to the installation of slates or
tiles. The period of such use should, however, be
kept to a minimum. Advice should be sought from
the Certificate holder."
For the full BBA of this product please visit:
http://www.bbacerts.co.uk/certs/41/4199i1_web.pdf
Roofline Building Products Ltd, is a Trading name of Ventilation Solutions Ltd
For more information or advise please feel free to visit one of our websites:
www.rooflineuk.com
www.vsluk.com
Thanks
Adam King
