90mm Celotex Thermaclass Cavity Wall 21 Full Fill Insulation Board T&G 1190mm x 450mm (3.21m2/Pack)
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Key Features
- {{home}} Low Global Warming Potential (GWP)
- {{public}} Zero Ozone Depletion Potential (ODP)
Technical Specification
| URN: | 3002375 |
|---|---|
| Brand: | Celotex |
| Application: | Full Fill Cavity Wall |
| Material Type: | PIR (Polyisocyanurate) |
| Thickness: | 90mm |
| Width: | 450mm |
| Length: | 1190mm |
| Weight: | 1.5kg |
| Sales Unit: | Pack |
| Sales Unit Coverage: | 3.21m2 |
| Pieces Per Pack: | 6 |
| Fire Rating: | Euroclass F |
| Thermal Conductivity: | 0.021W/mK |
| Compressive Strength: | 120kPa |
| Certification: | BBA Approved (24/7312) |
| Facing: | Low Emissivity Foil (Both Sides) |
| Edge: | Tongue and Groove |
Technical Downloads
Product Overview
Celotex Thermaclass Cavity Wall 21 Full Fill Insulation Board with a 90mm thickness and 1190mm × 450mm dimensions.
High-performance rigid polyisocyanurate (PIR) insulation board designed for use in full fill masonry cavity wall applications. Manufactured with a low emissivity foil facing, it delivers exceptional thermal conductivity of 0.021 W/mK, helping achieve low U-values while reducing overall wall thickness requirements.
The tongue and groove edge profile provides a tight, secure fit, minimising air gaps and thermal bridging. The board can be installed as a full fill solution or with a residual cavity of up to 10mm to accommodate mortar squeeze and simplify installation.
Lightweight, rigid, and easy to handle, the board fits standard wall tie spacing, supporting fast, efficient on-site fitting. The 90mm thickness provides high insulation performance for standard-depth wall cavities in residential and commercial construction.
Features & Benefits
- Outstanding thermal performance: Declared thermal conductivity of 0.021 W/mK reduces wall thickness while achieving low U-values.
- High performance facer: Low emissivity foil facing improves performance in cavities with up to 10mm air space.
- Precision fit: Tongue and groove edge detail ensures close jointing and minimal thermal bridging.
- Ease of installation: Sized for standard wall tie spacing; light, rigid boards are simple to transport and fit.
- Certified performance: BBA certified for full fill cavity wall use under Certificate 16/5343.
- Thickness: 90mm board suitable for standard cavity wall depths in full fill applications.
Applications
- Full fill cavity walls: Suitable for use between masonry leaves in domestic and commercial buildings.
- New build housing: Provides excellent U-value compliance in energy-efficient walls.
- Residual cavity installation: Can be fitted with a 10mm residual cavity to accommodate mortar squeeze.
- Thermal upgrade projects: Ideal for meeting advanced energy performance requirements.
Installation Guidance
- Preparation: Ensure cavity surfaces are clean and free from debris before installation.
- Board placement: Install boards with tongue and groove joints interlocked and staggered in brick bond pattern.
- Fixing method: Secure with appropriate retaining clips to wall ties as construction progresses.
- Joint sealing: Ensure tight-fitting joints with no gaps; seal edges as required by specification.
- Residual cavity: Maintain up to 10mm air space where design requires.
- Protection: Keep boards dry and covered until fully installed.
Compliance & Performance
- Material specification: Rigid PIR insulation with low emissivity foil facing.
- Thermal conductivity: 0.021 W/m·K (to BS EN 13165).
- Fire performance: Euroclass E reaction to fire to BS EN 13501-1.
- Compressive strength: ≥120 kPa at 10% compression.
- Water vapour resistance: High resistance due to foil facing.
- Certification: BBA certified (No. 16/5343) for full fill cavity wall systems.
- Environmental compliance: Manufactured under ISO 14001:2015 Environmental Management System.
- Standards compliance: UKCA marked to BS EN 13165 for factory-made rigid polyurethane (PU) insulation.
- Important note: Install and maintain in accordance with Celotex guidance and BBA certification details.
Delivery & Returns Information
Delivery charges vary by product category and order value. Items may ship from different suppliers and arrive separately, so delivery charges can be shown per part of your order at checkout.
Standard (Nationwide) Delivery
| Insulation, Plasterboard and Drylining Products | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £400 | £45 ex. VAT |
| Over £400 ex. VAT | FREE |
Express Delivery
| Express Delivery - Insulation and Plasterboard & Drylining | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £400 | £90 ex. VAT |
| Over £400 ex. VAT | £55 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 |
How delivery works
We work with a nationwide network of trusted suppliers. Items in your basket may be supplied by different suppliers and delivered separately. Where this applies, you will see delivery charges shown at checkout for each part of your order. We always aim to group products from the same supplier to keep delivery costs as low as possible.
Delivery areas
Delivery charges apply to mainland UK, excluding: AB, CA, CF, DD, DG, EH, EX, FK, KA, KW, KY, IV, LA, LD, LL, ML, NP, PA, PH, PL, SA, SY, TR, TQ and TD.
If your address is in one of these areas, we will contact you before processing your order to confirm any additional costs. We do not currently offer delivery outside the UK mainland.
What to expect on delivery day
- Deliveries are typically kerbside.
- Please ensure someone is on-site to accept delivery. For heavier items, help with offloading may be required.
- Many building materials arrive on large vehicles. If access is restricted, a specialist vehicle such as a HIAB may be required and could incur an additional charge.
Why delivery can cost more than typical parcel delivery
Building materials often travel on larger vehicles and usually carry fewer drops per run than parcel networks. That is why delivery charges can be higher than standard e-commerce shipping.
Returns
Returns depend on what you have bought and whether there is anything wrong with it. For full details on eligibility, timeframes, and exclusions, please see our full policy.
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