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16 Reviews
View Product Reviews25mm Celotex TB4025 PIR Insulation Board 2400mm x 1200mm
| 16+ boards | 30+ boards | 48+ boards |
| £10.47ex. VAT | £10.36ex. VAT | £10.15ex. VAT |
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Tomorrow
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Mon 22 Sep
- 0days
- 5hrs
- 37mins
- 1secs
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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 £300 | £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: | 25mm |
| Width: | 1200mm |
| Length: | 2400mm |
| Sales Unit: | Board |
| Sales Unit Coverage: | 2.88m2 |
| Brand: | Celotex |
| Manufacturer's Reference: | TB4025 |
| Weight: | 2.74kg |
| Thermal Conductivity: | 0.022W/mK |
Technical Downloads
Product Overview
Foil-faced PIR insulation board for use in floors, walls, and roofs.
Part of the TB4000 range, it is used to limit thermal bridging at reveals, junctions, and edges where insulation layers are interrupted.
At 25mm thick, this board fits shallow cavities and tight voids while bolstering thermal performance.
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 unventilated air gaps, cutting thermal transfer at junctions.
- TB4000 range (thermal bridging control): Improves continuity of insulation where up to 30% of fabric heat loss can otherwise occur.
- 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 25mm: Suited to shallow voids and cavities while upgrading insulation.
Applications
- Thermal bridging details (reveals, lintels, junctions): Limits cold spots, condensation risk, and heat loss where insulation layers are interrupted.
- Roofs (pitched/flat): Useful for upgrades at rafter lines, perimeter upstands, or overlaying to reduce bridging.
- Walls (timber frame/masonry): Applied at reveals, edges, or internally to improve continuity.
- Floors (beam & block, slab, timber): Commonly used as perimeter upstand insulation or for targeted slab upgrades.
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.
- 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
Used this to better insulate my outer house walls ahead of next winter
came on time and the driver was really kind
Good service and insulation
Good quality insulation
The delivery was prompt and the product is good value for money.
Thank you for a good service and product
Arrive on time, thanks
Easy to cut and easy to install under my floor between the joists. The price and service were excellent too.
Great insulation, bought 50mm and 100mm also at a competitive price.
Used this to reduce thermal bridging around columns and worked a charm! Very good price too!
Really cheap and I had the boards delivered in 2 working days, thank you
I was recommended this thermal insulation from a friend because it was simple to cut and install
grand
good insulation
reduces thermal bridging
great
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