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View Product Reviews90mm Celotex Thermaclass Cavity Wall 21 Full Fill Insulation Board T&G 1190mm x 450mm (3.21m2/Pack)
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90mm Thermaclass Cavity Wall 21 is designed for use in full fill cavity wall applications, boasting an impressively low thermal conductivity of just 0.021 W/m.K.
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Fri 28 Feb
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Product Overview
90mm Thermaclass Cavity Wall 21 is designed for use in full fill cavity wall applications, boasting an impressively low thermal conductivity of just 0.021 W/m.K.
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Delivery & Returns Information
All delivery charges are shown in your basket and are dependent on the total value of items in your basket based on product category.
This charge is based on delivery to mainland UK excluding the following postcodes: AB, DD, DG, KW, IV, LD, LL, PH, SA and SY. If your delivery address is in any of these postcode areas a member of our customer service team will contact you prior to processing your order should an additional delivery charge apply. We do not offer deliveries outside the UK mainland.
Standard (Nationwide) Delivery
| Insulation, Plasterboard and Drylining Products | ||
|---|---|---|
| ORDER VALUE | DELIVERY CHARGE | |
| Under £150 | £50 ex. VAT | |
| Between £150 - £400 ex. VAT | £35 ex. VAT | |
| Over £400 ex. VAT | FREE | |
| Timber & Sheet, Building Materials, Joinery and Gardens & Landscaping Products | ||
| ORDER VALUE | DELIVERY CHARGE | |
| Under £100 | £25 ex. VAT | |
| Between £100 - £250 ex. VAT | £20 ex. VAT | |
| Over £250 ex. VAT | FREE | |
| SuperFOIL and YBS products | ||
| ORDER VALUE | DELIVERY CHARGE | |
| Each item | £10 ex. VAT | |
| Over £350 ex. VAT of 1 brand | FREE | |
| Paving Stone Products | ||
| DELIVERY CHARGE | ||
| FREE | ||
| Screws & Fixings and Adhesives & Sealants | ||
| ORDER VALUE | DELIVERY CHARGE | |
| Under £100 | £7.50 ex. VAT | |
| Over £100 ex. VAT | FREE | |
| Thermafleece CosyWool Roll & SupaSoft Insulation | ||
| QUANTITY | DELIVERY CHARGE | |
| 1 | £30 ex. VAT | |
| 2 | £60 ex. VAT | |
| 3 to 12 | £70 ex. VAT | |
| 13 to 24 | £140 ex. VAT | |
| 25 to 36 | £210 ex. VAT | |
| 37 to 48 | £280 ex. VAT | |
| 49 to 60 | £350 ex. VAT | |
| 61+ | £420 ex. VAT | |
| Thermafleece CosyWool Slab, Thermafleece UltraWool & Thermafleece NatraHemp | ||
| QUANTITY | DELIVERY CHARGE | |
| 1 | £30 ex. VAT | |
| 2 | £60 ex. VAT | |
| 3 to 4 | £70 ex. VAT | |
| 5 to 8 | £140 ex. VAT | |
| 9 to 12 | £210 ex. VAT | |
| 13 to 16 | £280 ex. VAT | |
| 17 to 20 | £350 ex. VAT | |
| 21+ | £420 ex. VAT | |
| Block Pavers | ||
| ORDER VALUE | DELIVERY CHARGE | |
| Under £100 | £17.50 ex. VAT | |
| Between £100 - £200 ex. VAT | £30.50 ex. VAT | |
| Between £200 - £900 ex. VAT | £105 ex. VAT | |
| Over £900 ex. VAT | FREE | |
| Artificial Grass | ||
| ORDER VALUE | DELIVERY CHARGE | |
| Under £100 | £12 ex. VAT | |
| Between £100 - £200 ex. VAT | £16.50 ex. VAT | |
| Over £200 ex. VAT | £22 ex. VAT | |
| Doors and Feature Panelling | ||
| QUANTITY | DELIVERY CHARGE | |
| 1 to 2 | £35 ex. VAT | |
| 3 to 4 | £45 ex. VAT | |
| 5+ | £60 ex. VAT | |
|
* Deliveries of Doors and Panels to Scotland may incur additional costs and may have an extended delivery time of an additional 3 working days. Delivery to the postcodes below will be charged an additional delivery fee. Our customer service team will reach out to you if you order requires an additional delivery charge. This will be calculated based on the difference between the standard cost charged and the total cost outlined below:
Postcodes: KA1-29, IV1-39, AB, PH1-41, DD, PA1-19, KY, FK, FK15-21 - £90 ex VAT (total delivery cost) |
||
| Ironmongery | ||
| DELIVERY CHARGE | ||
| 1+ | £16.50 ex. VAT | |
| Specialist Products | ||
| DELIVERY CHARGE | ||
| FREE | ||
Express Delivery
| Express Delivery - Insulation and Plasterboard & Drylining | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £400 | £50 ex. VAT |
| Over £400 ex. VAT | £35 ex. VAT |
| Express Delivery - Timber & Sheet, Building Materials, Joinery and Gardens & Landscaping Products | |
| ORDER VALUE | DELIVERY CHARGE |
| Under £300 | £50 ex. VAT |
| Over £300 ex. VAT | £35 ex. VAT |
Returns
We offer a 30 day returns policy on any faulty products.
Key Features
- {{holiday_village}} Designed for full fill cavity wall applications
- {{thermostat}} Low emissivity foil facing for improved thermal performance
- {{menu_open}} Can be installed with up to a 10mm residual cavity
- {{check_circle}} Accommodates mortar squeeze
Technical Specification
| Material Type: | PIR |
|---|---|
| Thickness: | 90mm |
| Width: | 450mm |
| Length: | 1190mm |
| Pieces Per Pack: | 6 |
| Sales Unit: | Pack |
| Sales Unit Coverage: | 3.21m2 |
| Brand: | Celotex |
| Thermal Conductivity: | 0.021W/mK |
Technical Downloads
About 90mm Thermaclass Cavity Wall 21
- A high-performance insulation board specifically engineered for full-fill cavity wall applications.
- Exceptional thermal conductivity of just 0.021 W/mK.
- Constructed with a Polyisocyanurate (PIR) foam core and finished with low-emissivity foil facings.
- Tongue and groove (T&G) edge promotes a continuous insulation layer while offering protection against wind-driven rain.
- Perfectly suited for both residential and commercial projects, providing long-lasting performance.
- Effectively regulates indoor temperatures, ensuring occupant comfort while complying with UK Building Regulations.
Applications
- Full fill cavity wall insulation
Benefits
- Excellent Thermal Performance: Thermal conductivity of 0.021 W/m.K reduces the amount of insulation needed to meet target U-values.
- High-Performance Facer: Enhances thermal performance in sealed cavity air spaces, improving achievable U-values (based on a residual cavity of 10mm).
- Moisture Resistant: Designed to resist the transfer of moisture through the cavity, preventing damp and mould formation and improving the overall durability and comfort of the building.
- Easy Installation: Sized to fit standard cavity wall tie spacing, the boards are light and rigid, simplifying transportation, handling, and fitting.
- Tongue and Groove Design: Streamlines installation, ensuring a tight fit between boards and minimising gaps that could compromise insulation effectiveness.
- BBA Certified: Assessed and certified by the BBA (British Board of Agrément) for use in defined full-fill cavity wall applications, ensuring its suitability when installed, used, and maintained according to the certification guidelines.
Certifications
- BBA approved - certificate 16/5343 (Full Fill Cavity Walls)
- CE Marked (20.DOPTCCW-01) to BS EN 13165
- Euroclass E Reaction to Fire classification, according to BS EN 13501-1
- Environmental Management System - ISO 14001:2015
- Quality Management Standard - ISO 9001:2015
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