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12 Reviews
View Product Reviews120mm Celotex XR4120 PIR Insulation Board 2400mm x 1200mm
| 6+ boards | 10+ boards | 16+ boards |
| £33.42ex. VAT | £33.08ex. VAT | £32.40ex. VAT |
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Express Delivery
Fri 19 Sep
Standard Delivery
Mon 22 Sep
- 0days
- 16hrs
- 59mins
- 0secs
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Buy now. Pay with Klarna at your own pace.
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- Choose Clearpay at checkout to pay later with Pay in 4.
- Complete your purchase with the first payment today.
- Remaining payments are taken automatically.
Clearpay is unregulated credit. Use responsibly. 18+, T&Cs and late fees apply at clearpay.co.uk/en-GB
Clearpay lends you a fixed amount of credit so you can pay for your purchase over 4 instalments, due every 2 weeks. Ensure you can make repayments on time. You must be 18+ and a permanent UK resident (excl Channel Islands). Clearpay charges a £6 late fee for each late instalment and a further £6 if it’s still unpaid 7 days later. Late fees are capped at £6 for orders under £24 and the lower of £24 or 25% of the order value for orders over £24. Missed payments may affect your ability to use Clearpay in the future and your details may be passed onto a debt collection agency working on Clearpay’s behalf. Clearpay is credit that is not regulated by the Financial Conduct Authority. T&Cs and other eligibility criteria apply at clearpay.co.uk/terms
Product Overview
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, FK, KW, IV, LA, LD, LL, NP, PA, PH, SA, SY
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
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Core Products Core
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|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £300 ex. VAT | £20 ex. VAT |
| Over £300 ex. VAT | FREE |
Core Delivery charges apply only when all products in an order that have equivalents are accepted as such. If even one product cannot be substituted with an equivalent, the entire order will not qualify for Core Delivery charges.
| 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 | £15 ex. VAT |
| Between £100 - £300 ex. VAT | £10 ex. VAT |
| Over £300 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
- {{home}} Use in floors, framed walls and pitched roofs
- {{grade}} Aluminium composite facing on both sides
- {{thermostat}} 0.022 W/mK thermal conductivity
- {{build}} Easy to handle and install
- {{public}} Zero Ozone Depletion Potential (ODP)
- {{verified_user}} BBA certified
Technical Specification
| Material Type: | PIR |
|---|---|
| Thickness: | 120mm |
| Width: | 1200mm |
| Length: | 2400mm |
| Sales Unit: | Board |
| Sales Unit Coverage: | 2.88m2 |
| Brand: | Celotex |
| Manufacturer's Reference: | XR4120 |
| Weight: | 14.2kg |
| Thermal Conductivity: | 0.022W/mK |
Technical Downloads
Product Overview
Foil-faced PIR insulation board for use in floors, walls, and roofs.
Part of the XR4000 range, it provides extra resistance through increased thickness, helping achieve low U-values with a single board layer.
At 120mm thick, this board is a common choice for achieving strong thermal performance in deeper cavities or roof constructions.
Features & Benefits
- Thermal conductivity (0.022 W/m·K): Reduces the thickness required to meet U-value targets.
- Low-emissivity foil facings: Reflect radiant heat across cavity air spaces, improving overall efficiency.
- XR4000 range (extra resistance): Suited to achieving low U-values with a single layer in roofs, walls, and floors.
- Rigid PIR core: Lightweight yet robust, easy to cut and install with standard tools.
- Moisture resistance: Closed-cell core prevents water uptake and preserves thermal performance.
- Environmental credentials: Zero ODP, low GWP blowing agent, and BRE Green Guide Rating A.
- BBA certified (17/5405, 16/5352): Independent assurance of performance across roofs, walls, and floors.
- Board size 2400 x 1200mm: Large-format sheets reduce installation time.
- Thickness 120mm: Practical thickness for achieving low U-values in roof and wall applications.
Applications
- Extra resistance: Thick board designed to achieve low U-values in single-layer applications for energy-efficient and low-energy projects.
- Roofs (pitched/flat): Between rafters, under rafters, over-rafter sarking, or between flat roof joists.
- Walls (timber frame/masonry): Timber frame linings, partial-fill cavity upgrades, or solid masonry internal linings.
- Floors (beam & block, slab, timber): Beam & block floors, concrete slabs, suspended timber floors, or slab overlays.
Installation Guidance
- Cut and fit tightly: Use a knife or fine-tooth saw; maintain close joints to avoid thermal bypass.
- Seal or tape as specified: Ensures continuity with air and vapour control layers.
- Fix securely: Mechanical fixings, adhesives, or retention by framing depending on application.
- Protect on site: Store boards flat, dry, and covered until required.
Compliance & Performance
- Thermal conductivity: 0.022 W/m·K (BS EN 12667).
- Compressive strength: ≥140 kPa (BS EN 826).
- Reaction to fire: Euroclass E (BS EN 13501-1).
- Environmental performance: Zero ODP, low GWP, BRE Green Guide Rating A.
Customer Reviews
easy to work with and cut
Great customer experience from start to finish
Really lightweight considering how big each board looks
Exactly what I needed for my loft conversion
I always buy Celotex, the service of Materials Market was great
Came on time and cheapest I found online
Really easy to install
Great insulation at a good price
Excellent thermal performance. Foil facings on both sides meant I did need to buy some additional tape which was also inexpensive.
Great service from start to finish
excellent boards
durable
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