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50mm Celotex CW4050 Cavity Wall Insulation Board 1200mm x 450mm (5.94m2/Pack)
| 10+ packs | 15+ packs | 20+ packs |
| £49.13ex. VAT | £48.59ex. VAT | £47.11ex. VAT |
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PIR cavity wall insulation board for partial fill construction. Suitable for masonry cavity walls. Fits 75mm cavities, maintaining a 25mm residual gap for ventilation and moisture control.
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Fri 21 Nov
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- 3hrs
- 56mins
- 47secs
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Product Overview
PIR cavity wall insulation board for partial fill construction. Suitable for masonry cavity walls. Fits 75mm cavities, maintaining a 25mm residual gap for ventilation and moisture control.
Delivery & Returns Information
How Our Delivery Works
We work with a nationwide network of trusted suppliers. As a result, items in your basket may be supplied by different suppliers and delivered separately. Where this applies, you'll see multiple delivery charges at checkout. We always aim to group products from the same supplier to keep delivery costs as low as possible.
Delivery Areas & Charges
Delivery charges listed on our website apply to mainland UK, excluding the following postcode areas: AB, CF, DD, DG, EH, FK, KA, KW, KY, IV, LA, LD, LL, ML, NP, PA, PH, SA, SY & TD
If your delivery address falls within one of these postcode areas, we’ll be in touch before processing your order to confirm any additional delivery costs.
Please note: We do not currently offer delivery outside the UK mainland.
Standard (Nationwide) Delivery
| Insulation, Plasterboard and Drylining Products | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £350 | £35 ex. VAT |
| Over £350 ex. VAT | FREE |
| Timber & Sheet, Building Materials, Joinery and Gardens & Landscaping Products | |
| ORDER VALUE | DELIVERY CHARGE |
| Under £100 | £20 ex. VAT |
| Over £100 ex. VAT | FREE |
| Screws & Fixings and Adhesives & Sealants | |
| ORDER VALUE | DELIVERY CHARGE |
| Under £50 | £5 ex. VAT |
| Over £50 ex. VAT | 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
- {{fitness_center}} Rigid partial fill cavity wall insulation
- {{layers}} Aluminium composite facing on both sides
- {{device_thermostat}} 0.022 W/mK thermal conductivity
- {{shield}} BBA certified
Technical Specification
| Material Type: | PIR |
|---|---|
| Thickness: | 50mm |
| Width: | 450mm |
| Length: | 1200mm |
| Pieces Per Pack: | 11 |
| Sales Unit: | Pack |
| Sales Unit Coverage: | 5.94m2 |
| Brand: | Celotex |
| Manufacturer's Reference: | CW4050 |
| Weight: | 11.4kg |
| Thermal Conductivity: | 0.022W/mK |
Technical Downloads
Product Overview
Celotex CW4050 Cavity Wall Insulation Board measuring 50mm thick and 1200mm × 450mm in size.
High-performance rigid polyisocyanurate (PIR) insulation board designed for use in masonry cavity wall constructions. The board provides excellent thermal performance while maintaining a lightweight, easy-to-handle format for quick installation.
Manufactured with a low-emissivity foil facing on both sides, it enhances the thermal resistance of air spaces within the cavity, contributing to improved overall wall U-values. The PIR core delivers reliable long-term stability and moisture resistance, ensuring consistent insulation performance over the building’s lifespan.
The 50mm thickness fits 75mm cavities, maintaining a 25mm residual gap for ventilation and moisture control.
Features & Benefits
- High thermal efficiency: PIR core achieves low thermal conductivity for superior insulation performance.
- Foil facings: Low-emissivity aluminium facings improve cavity reflectivity and reduce heat loss.
- Lightweight design: Easy to cut and fit between wall ties, reducing installation time and waste.
- Moisture resistance: Closed-cell structure minimises water absorption for reliable in-cavity performance.
- Durability: Rigid board maintains dimensional stability and compressive strength during installation.
- Thickness: 50mm board fits 75mm cavities, maintaining a 25mm residual gap for ventilation and moisture control.
Applications
- Masonry cavity walls: Designed for use between inner and outer leaves of traditional brick and block construction.
- Partial-fill systems: Suitable for retaining an air gap while improving overall wall insulation.
- New build and refurbishment: Applicable for both domestic and commercial building envelopes.
- Energy efficiency upgrades: Reduces heat loss and improves compliance with current building regulations.
Installation Guidance
- Preparation: Ensure wall cavities are clean, free from mortar droppings, and dry prior to installation.
- Board placement: Fit boards between wall ties in a staggered pattern with tight-fitting joints.
- Fixing method: Use retaining clips to secure boards against the inner leaf as construction progresses.
- Joint sealing: Tightly butt all edges; tape or seal where specified to prevent thermal bridging.
- Protection: Keep boards dry on-site and avoid exposure to prolonged sunlight.
Compliance & Performance
- Material specification: Rigid polyisocyanurate (PIR) insulation with aluminium foil facings both sides.
- Thermal conductivity: 0.022 W/m·K.
- Fire performance: Class E reaction to fire (BS EN 13501-1).
- Water vapour resistance: Foil facing provides high resistance to moisture ingress.
- Compressive strength: Typically exceeds 120 kPa at 10% compression.
- Environmental compliance: Manufactured under ISO 14001 with zero ODP and low GWP blowing agents.
- Important note: Installation must follow Celotex guidance to maintain declared thermal performance.
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