Important Information: For all updates and Celotex announcements since June 2017, please see the links below...  See more

Declared lambda values - Read more >

5000 Class 0 testing - Read more >

Rainscreen cladding & RS5000 - Read more >

Celotex CW4000

High performance PIR insulation for partial fill cavity wall applications.

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IMPORTANT: We have recently identified a compliance issue relating to our calculation and testing of the lambda value of products in our 4000 and 5000 range and the Crown-Bond and Crown-Fix products within Crown Flat Roofing range. Please note that CW4000 manufactured after 15 December 2017 will be marketed from January as Celotex CW3000 with a declared lambda value of 0.023 W/mK. 

Please use the link below to read our full statements regarding declared lambda:

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As a high performance partial fill cavity wall insulation board featuring low emissivity foil facings, Celotex CW4000 offers enhanced thermal performance as cavity wall insulation when compared to typical PIR products.

Celotex CW4000’s enhanced features deliver thinner solutions that meet target U-values as required by Building Regulations including Part L and BREEAM.

  • Board size: 1200 x 450mm
  • Thickness : 40-100mm
  • Lambda: 0.022 W/mK
  • Facer: Low emissivity foil facings

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Featuring low emissivity foil facings, Celotex CW4000 is a simple solution for partial fill cavity walls that:

  • Offers high performance PIR insulation with low emissivity foil facings offering enhanced thermal performance within cavity air spaces
  • Is certified under BBA certificate number 16/5343
  • Is available as a BIM object
  • Has zero ozone depletion potential (zero ODP) and low global warming potential (GWP)
  • Future proofs the energy performance of new and existing buildings

Did you know?

Not only can you calculate detailed partial fill U-value calculations here on the website, but we also have an experienced team of energy assessors who specialise in SAP or SBEM calculations, water calculations, airtightness testing plus much more. Energy & sustainability requirements are getting more and more difficult so let our experienced team take away the hassle & ensure you are completely compliant. Contact today.