Celotex Isover

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.