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Celotex  |  SKU: TC1115

5 Boards x 115mm Celotex Thermaclass Cavity Wall 21 Insulation - 1190mm x 450mm

£78.86 Ex VAT
£94.63 Inc VAT

Celotex Thermaclass is a purpose-made PIR cavity wall insulation designed for full-fill installation typically in 125mm cavities.

Nationwide Delivery in 3-5 WORKING DAYS

  • £35 ex VAT (only £25 with order value over £120 inc vat) Delivery
  • FREE DELIVERY OVER £500

Need a next-day or named day delivery? Call Us.


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 Agreement (BBA) as fit for use in defined full fill cavity wall applications if installed, used and maintained as set out in the certificate.

Thickness: 115 mm
Length: 1190 mm
Width: 450 mm
Coverage: 2.68 m²
Thermal conductivity: 0.021 W/mK
No Boards: 5
Country Origin: UK
  • Size
    1190mm x 450mm
  • Coverage (m²)
    2.6775
  • Thickness
    115mm

Do You Ship to My Address?

We deliver to most mainland UK addresses. If you are in one of the areas listed below and are unable to checkout, please give us a call to put together a custom quote.

Northern Ireland (BT), Isle of Wight (PO30-37), Isle of Man (IM), Scottish Highlands and Orkney Isles (PA, ML, EH, KA, G, KY, PH, DD, AB, IV, KW), Outer Hebrides and the Shetland Isles (HS, ZE) will incur additional charges and may also experience delivery delays.

How Much Will My Delivery Cost?

You can work out the cost of delivery on your order before checkout by heading to our Delivery Info page.

How Long Will Delivery Take?

We aim to deliver your items in 3 - 5 Working Days unless otherwise specified (eg - Sheds and Paving Kits). After you have placed your order, we will process your order and book a delivery day - which will then be sent to you via Email.

If have a specific request, please do give our team a call on 01156976800 and we will do our best to help.

What If I Need to Return Something?

If for any reason you wish to return your purchase, we will offer a refund or an exchange as long as this is requested within 14 days of receiving your order.

A manufacturer’s restocking charge may also apply on certain products such as non-stock items, which may be up to 30% of the purchase price, and you will be notified of this amount when you request a refund or exchange.

For full information visit our Returns Policy.

Celotex

5 Boards x 115mm Celotex Thermaclass Cavity Wall 21 Insulation - 1190mm x 450mm

£78.86 Ex VAT
£94.63 Inc VAT

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 Agreement (BBA) as fit for use in defined full fill cavity wall applications if installed, used and maintained as set out in the certificate.

Thickness: 115 mm
Length: 1190 mm
Width: 450 mm
Coverage: 2.68 m²
Thermal conductivity: 0.021 W/mK
No Boards: 5
Country Origin: UK
View product
Thickness: 115mm