Celotex Isover

Celotex CW4000

Celotex CW4000 is an easy to install polyisocyanurate (PIR) insulation board with excellent thermal performance, featuring a low emissivity foil facing. Available in thicknesses from 40mm to 100mm, it can be considered for use in partial fill cavity wall applications.

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  • External Walls – partial fill cavity wall

Product Features

  • Lightweight 1200x450mm boards
  • Squared edges
  • Low emissivity foil facing
  • Achieves a BRE Green Guide A rating
  • BBA approved – certificate 16/5343 (Partial Fill Cavity Walls)

Product Properties

  • Board / Roll size: Width 450mm, Length 1200mm
  • Thickness : 40-100mm
  • Material: PIR

Product Performance

  • Lambda: 0.022 W/m.K
  • Reaction to Fire: Euroclass E Reaction to Fire classification, according to BS EN 13501-1. Products with this level of classification are not provided with a rating for smoke emission

Product Benefits

  • Excellent thermal performance with a thermal conductivity of 0.022 W/m.K, reducing the thickness of insulation required to hit the target U-value.
  • Low emissivity foil facing provides improved thermal performance in sealed cavity air spaces, improving the achievable U-value.
  • Easy to install – The boards are light and rigid assisting with ease of transportation, handling and fitting. They are sized to fit standard wall tie spacing for ease of installation.
  • BBA certified - Celotex CW4000 has been assessed by the BBA as fit for use in defined partial fill cavity wall applications if installed, used and maintained as set out in the certificate. Please read the certification for full details and restrictions.
  • Celotex CW4000 achieves a BRE Green Guide Rating of A, which can assist in demonstrating environmental performance in your BREEAM assessments. Please visit the Celotex page at greenbooklive.com for further details.

Key Considerations

When using Celotex CW4000, you need to satisfy yourself that use of the product meets all relevant national Building Regulations and guidance as well as local, national and other applicable standards relevant for your construction or application, including requirements in relation to fire and applicable height restrictions.

Please refer to the following product documents:

Celotex CW4000 should not be used in the external walls of buildings over 18 metres in height (England and Wales) or 11 metres in height (Scotland). Recent changes to Building Regulations mean that only non-combustible insulation or insulation of limited combustibility can be used in buildings of that height.