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115mm Celotex Thermaclass 21 Cavity Insulation - 2.67m2 pack

£75.00 (ex. VAT)
115mm PIR Insulation Board ideal for full fill cavity wall applications leaving a 10mm residual cavity
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115mm Thermaclass Cavity Wall 21 is a rigid polyisocyanurate (PIR) insulation solution from Celotex for masonry full fill cavity wall applications. Featuring a tongue and groove edge profile, Thermaclass Cavity Wall 21 has an excellent thermal performance of 0.021 W/m.K (“lambda 21”) which can help to achieve lower U-values without increasing the overall wall thickness. For wall constructions featuring a 10mm residual cavity, the low-emissivity foil facing increases the thermal performance in sealed cavity air spaces, improving the achievable U-value. Thermaclass Cavity Wall 21 has been assessed by the British Board of Agrément (BBA) as fit for use in defined full fill cavity wall applications if installed, used and maintained as set out in the certificate.

  • Board size: 1190 x 450mm
  • Thickness : 115mm
  • Lambda: 0.021 W/mK
  • Facer: Low emissivity foil facings
  • 5 Boards per pack
  • 16 packs per pallet = 42.8m2
Please note : Due to recent national shortages of PIR insulation, We now offer Celotex, Ecotherm, Recticel and Iko to help to offer a speedy delivery. You may be offered an alternative brand due to local stock availability.

Please contact us if you require any further information or a product data sheet.
Product Type:
PIR Insulation
Edit Product Type:
PIR Insulation
115x450x1190MM (0.535 M²)
3 - 5 working
Celotex Insulation
Product Code: