.jpg)
.jpg)
.jpg)
1 Review
View Product Reviews20mm Celotex TB4020 PIR Insulation Board 2400mm x 1200mm
Coverage required
Nationwide Delivery
Tue 6 May
- 0days
- 8hrs
- 31mins
- 21secs
Learn more
Pay in 3 interest-free payments
Split your purchase of £13.71 into 3 with no sign-up fees or late fees.
£4.57
today
£4.57
1 month
£4.57
2 months
How it works
- Choose PayPal at checkout to pay later with Pay in 3.
- Complete your purchase with the first payment today.
- Remaining payments are taken automatically.
Pay in 3 is a form of credit, so carefully consider whether the purchase is affordable and how you will make the repayments. Be aware of the possible impact of using Pay in 3 and of missing payments, including making other borrowing more difficult or more expensive. Pay in 3 eligibility is subject to status and approval. 18+ UK residents only. Available for purchases of £30 to £2,000. Terms and conditions apply. PayPal Pay in 3 is a trading name of PayPal (Europe) S.à r.l. et Cie, S.C.A. 22-24 Boulevard Royal L-2449, Luxembourg.
Learn more
Buy now. Pay with Klarna at your own pace.
Get what you need for your next project, choose how you pay.
Pay in 30 days
£13.71
Pay in full
Klarna's Pay in 30 days is an unregulated credit agreement. Borrowing more than you can afford or paying late may negatively impact your financial status and ability to obtain credit. 18+, UK residents only. Subject to status. T&Cs and late fees apply.
Pay over time
£4.57
Every 30 days
Pay in 3
£4.57
today
£4.57
in 30 days
£4.57
in 60 days
Klarna's Pay in 3 is an unregulated credit agreement. Borrowing more than you can afford or paying late may negatively impact your financial status and ability to obtain credit. 18+, UK residents only. Subject to status. T&Cs and late fees apply.
How it works
- At checkout select Klarna.
- Choose your payment plan.
- Different payment plans may be shown depending on the purchase amount and credit score.
- Complete your checkout.
- The amount will be charged based on the payment plan you chose.
Learn more
Pay in 4 interest-free payments
Split your purchase of £13.71 into 4 with no sign-up fees or late fees. Your purchase will be split into 4 payments, payable every 2 weeks
£3.43
today
£3.43
second payment
£3.43
third payment
£3.43
fourth payment
How it works
- 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 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
Frequently Bought With
+-+Photo.jpg)
.jpg)
Klarna's Pay in 3 / Pay in 30 days are unregulated credit agreements. Borrowing more than you can afford or paying late may negatively impact your financial status and ability to obtain credit. 18+, UK residents only. Subject to status. Late fees may apply. Ts&Cs apply
Clearpay is unregulated credit. Use responsibly. 18+, T&Cs and late fees apply at clearpay.co.uk/apply
Delivery & Returns Information
All delivery charges are shown in your basket and are dependent on the total value of items in your basket based on product category.
This charge is based on delivery to mainland UK excluding the following postcodes: AB, CF, DD, DG, KW, IV, LD, LL, NP, PH, SA and SY. If your delivery address is in any of these postcode areas a member of our customer service team will contact you prior to processing your order should an additional delivery charge apply. We do not offer deliveries outside the UK mainland.
Standard (Nationwide) Delivery
| Insulation, Plasterboard and Drylining Products | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £150 | £50 ex. VAT |
| Between £150 - £400 ex. VAT | £35 ex. VAT |
| Over £400 ex. VAT | FREE |
| Timber & Sheet, Building Materials, Joinery and Gardens & Landscaping Products | |
| ORDER VALUE | DELIVERY CHARGE |
| Under £100 | £25 ex. VAT |
| Between £100 - £250 ex. VAT | £20 ex. VAT |
| Over £250 ex. VAT | FREE |
| SuperFOIL and YBS products | |
| ORDER VALUE | DELIVERY CHARGE |
| Each item | £10 ex. VAT |
| Over £350 ex. VAT of 1 brand | FREE |
| Screws & Fixings and Adhesives & Sealants | |
| ORDER VALUE | DELIVERY CHARGE |
| Under £100 | £7.50 ex. VAT |
| Over £100 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: | 20mm |
| Width: | 1200mm |
| Length: | 2400mm |
| Sales Unit: | Board |
| Sales Unit Coverage: | 2.88m2 |
| Brand: | Celotex |
| Manufacturer's Reference: | TB4020 |
| Weight: | 2.28kg |
| Thermal Conductivity: | 0.022W/mK |
Technical Downloads
About 20mm Celotex
- TB4020 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 in a partition wall and worked well. One of the best thinner solutions for insulation!
Leave a Review
Related Articles
How to Insulate Under Floorboards Without Removing
How To Install Celotex Insulation Boards
Celotex Floor Insulation Guide
