Celotex Isover

Celotex XR4000 insulation board

Celotex XR4000 is a high performance, easy to install polyisocyanurate (PIR) insulation board featuring a low emissivity foil facing. Available in thicknesses from 110mm to 200mm, it can be considered for roof, wall and floor applications.

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Suitable Applications

  • Concrete Slab Ground Floors
  • Suspended Timber Ground Floors
  • Beam and Block Ground Floors
  • Upgrading existing Concrete Slab Floors
  • Timber Frame External Wall Between Studs
  • Pitched Roof - Between Rafters
  • Pitched Roof - Loft insulation
  • Flat Roof - Balconies and Terraces
  • Flat Roof - Between and Under Joists

Product Features

  • Lightweight 2400 x 1200mm boards
  • Low emissivity foil facing
  • Achieves a BRE Green Guide A rating
  • BBA approved – certificates 16/5352, 17/5405

Product Properties

  • Board / Roll size: Width 1200mm, Length 2400mm
  • Thickness : 110-200mm
  • Material: PIR

Product Performance

  • Lambda: 0.022 W/m.K
  • Reaction to Fire: Reaction to Fire: Euroclass E Reaction to Fire classification, according to EN 13501-1

Product Benefits

  • Excellent thermal conductivity - 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 cavity air spaces, improving the achieved U-value
  • Easy to install – lightweight boards are straightforward to handle, fit and transport
  • BBA certification - third-party verification that the product has been assessed for its defined applications and is compliant with the relevant Building Regulations.