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16 Reviews
View Product Reviews25mm Celotex TB4025 PIR Insulation Board 2400mm x 1200mm
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Tue 9 Sep
Standard Delivery
Wed 10 Sep
- 2days
- 19hrs
- 29mins
- 51secs
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- Choose Clearpay at checkout to pay later with Pay in 4.
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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, 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
|
Core Products Core
|
|
|---|---|
| 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 |
| 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
- {{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
About 25mm Celotex
- TB4025 is a high-performance PIR insulation board designed to combat thermal bridging (TB) in walls, roofs, and floors.
- BBA-certified for reliability and compliance with UK Building Regulations.
- Ideal for both new-build and retrofit projects where minimising heat loss is essential.
- Delivers excellent thermal efficiency with a low thermal conductivity of 0.022 W/m·K.
- Low-emissivity foil-facing enhances performance by reflecting radiant heat within cavity air spaces.
- Lightweight yet rigid design simplifies handling, cutting, and installation.
- Manufactured with sustainability in mind, offering Zero Global Warming Potential (GWP) and Zero Ozone Depleting Potential (ODP).
Applications
Roofs
- Pitched Roof Insulation: Below Timber Rafters, Above Timber Rafters
Walls
- External Wall Insulation: Timber Frame Internal Linings, Masonry Cavity Internal Linings, Solid Masonry Internal Linings
- Partition Walls
Floors
- Ground Floor Insulation: Beam & Block (Perimeter Upstand), Concrete Slab (Perimeter Upstand), Suspended Timber Joists (Perimeter Upstand), Upgrading Existing Concrete Slab (Perimeter Upstand)
Benefits
- Excellent Thermal Performance - 0.022 W/m·K thermal conductivity reduces insulation thickness required to meet U-values.
- Moisture Resistant - Prevents water absorption, maintaining thermal efficiency.
- Environmentally Responsible - Zero GWP and ODP, supporting sustainable construction.
- Cost-Effective - Provides high performance at a competitive price.
- Non-Toxic - Safe to handle and install, with no harmful emissions.
- Low-Emissivity Foil Facings - Improves thermal insulation within cavity air spaces.
Certifications
- Spread of Flame: Euroclass E Reaction to Fire classification (BS EN 13501-1).
- Thermal Conductivity: 0.022 W/m·K (BS EN 12667).
- Compressive Strength: ≥140kPa (BS EN 826).
- BRE Green Guide Rating of A - Supports BREEAM sustainability assessments.
- BBA Certified - Independently assessed for performance and compliance.
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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