Celotex CW4000
Celotex CW4000 is a high performance, easy to install polyisocyanurate (PIR) insulation board featuring a low emissivity foil facing. Available in thicknesses from 40mm to 100mm, it is suitable 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
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 EN 13501-1
Product Benefits
- Excellent thermal performance - decreasing the thickness of insulation required to hit the required U-value, optimising space in the construction design and helping to reduce the heating and cooling costs within the building
- Low emissivity foil facing provides improved thermal performance in sealed cavity air spaces, improving the achievable U-value.
- Easy to install – lightweight boards are straightforward to handle, fit and transport. Boards are 1200x450mm to fit between standard wall tie spacing
- BBA certification - third-party verification that the product has been assessed for its defined applications and is compliant with the relevant Building Regulations.