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90mm Celotex Thermaclass Cavity Wall 21 - Rigid PIR Full Fill Cavity Insulation Board (pack of 6)

90mm Celotex Thermaclass Cavity Wall 21 - Rigid PIR Full Fill Cavity Insulation Board (pack of 6)
Guide Price
90mm Celotex Thermaclass Cavity Wall 21 - Rigid PIR Full Fill Cavity Insulation Board (pack of 6)
Guide Price: £138.02 (£165.62 inc VAT)
Price per m2: £42.60/m2 (£51.12 inc VAT)
  • Product Code: A1-4775
  • Delivery Time: 2 - 4 days
  • Brand: Celotex (Tech. support: 01473820850)
  • Model: 1190x450mm - 3.24m2
  • Weight: 9.07kg
Our ratings on 14-09-2026:
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4.8 out of 5

90mm Celotex Thermaclass Cavity Wall 21 - Rigid PIR Full Fill Cavity Insulation Board (pack of 6)

Width: 450mm
Length: 1190mm
Pack Quantity: 6
Weight/m2: 2.8kg
Weight: 9.07kg
Thermal Conductivity: 0.021W/mK
R-Value: 4.25m2K/W
Fire Rating (Reaction to Fire): E

90mm Celotex Thermaclass Cavity Wall 21 is a high performance rigid PIR full fill cavity insulation board with low emissivity foil facings offering enhanced thermal performance (0.021 W/m.K) within cavity air spaces. It can be installed with up to a 10mm residual cavity or as a full fill solution with no residual cavity. Celotex Thermaclass Cavity Wall 21 is manufactured from rigid polyisocyanurate (PIR) using a blend of blowing agents that have zero ozone depletion potential (zero ODP) and low global warming potential (GWP).

APPLICATION

  • Full fill cavity insulation,
  • Can be installed with up to a 10mm residual cavity

CHARACTERISTICS
  • Excellent thermal performance, 
  • Lightweight and easy to install,
  • Tongue and groove for easy installation,
  • The boards are sized to fit standard cavity wall tie spacing,
  • Can be used up to 18 metres height (England and Wales),
  • Includes low emissivity foil facings giving improved thermal insulation performance within cavity air spaces,
  • Has excellent dimensional stability,
  • Provides reliable long term energy savings for buildings.
CERTIFICATION
  • BBA certified, 
  • Euroclass E Reaction to Fire classification, according to BS EN 13501-1,
  • Manufactured under Environmental Management System ISO 14001:2015,
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Guide Price
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Delivery Time: 1 - 5 working days
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Delivery Time: 1-3 working days
Celotex TB4030 is targeted at cut-to-fit applications between rafters or joists and enables users to achieve lower U-values with a single layer of insulation than has previously been possible. TB4012 is also appropriate for use in floors and walls. With low emissivity foil facings, TB4012 is manufac..
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Guide Price
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Delivery Time: 1-3 working days
Celotex TB4035 is targeted at cut-to-fit applications between rafters or joists and enables users to achieve lower U-values with a single layer of insulation than has previously been possible. TB4012 is also appropriate for use in floors and walls. With low emissivity foil facings, TB4012 is manufac..
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140mm Celotex Thermaclass Cavity Wall 21 - Rigid PIR Full Fill Cavity Insulation Board (pack of 4)
Guide Price
Brand: Celotex Model: 1190x450mm - 2.16m2
Delivery Time: up to 7 days
140mm Celotex Thermaclass Cavity Wall 21 is a high performance rigid PIR full fill cavity insulation board with low emissivity foil facings offering enhanced thermal performance (0.021 W/m.K) within cavity air spaces. It can be installed with up to a 10mm residual cavity or as a full fill solu..
Guide Price: £136.44
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