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View Product Reviews20mm Celotex TB4020 PIR Insulation Board 2400mm x 1200mm
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Key Features
- {{home}} Low Global Warming Potential (GWP)
- {{public}} Zero Ozone Depletion Potential (ODP)
Technical Specification
| URN: | 3001023 |
|---|---|
| Brand: | Celotex |
| Application: | Floors, Walls, and Roofs |
| Indoor/Outdoor Usage: | Indoor |
| Material Type: | PIR (Polyisocyanurate) |
| Thickness: | 20mm |
| Width: | 1200mm |
| Length: | 2400mm |
| Weight: | 2.28kg |
| Sales Unit: | Board |
| Sales Unit Coverage: | 2.88m2 |
| Fire Rating: | Euroclass F |
| Thermal Conductivity: | 0.022W/mK |
| Compressive Strength: | 140kPa |
| Density: | 31kg/m3 |
| Certification: | BBA Approved (25/7318) |
| Product Standard: | BS EN 13165 |
| Facing: | Low Emissivity Foil (Both Sides) |
| Edge: | Square |
| Manufacturer's Reference: | TB4020 |
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 20mm thick, this is the slimmest option in the range, suited to over-boarding, detail work, and space-constrained applications.
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 20mm: Slimmest PIR option, enabling insulation where space is most limited.
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.
Delivery & Returns Information
Delivery charges vary by product category and order value. Items may ship from different suppliers and arrive separately, so delivery charges can be shown per part of your order at checkout.
Standard (Nationwide) Delivery
| Insulation, Plasterboard and Drylining Products | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £400 | £45 ex. VAT |
| Over £400 ex. VAT | FREE |
Express Delivery
| Express Delivery - Insulation and Plasterboard & Drylining | |
|---|---|
| ORDER VALUE | DELIVERY CHARGE |
| Under £400 | £90 ex. VAT |
| Over £400 ex. VAT | £55 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 |
How delivery works
We work with a nationwide network of trusted suppliers. Items in your basket may be supplied by different suppliers and delivered separately. Where this applies, you will see delivery charges shown at checkout for each part of your order. We always aim to group products from the same supplier to keep delivery costs as low as possible.
Delivery areas
Delivery charges apply to mainland UK, excluding: AB, CA, CF, DD, DG, EH, EX, FK, KA, KW, KY, IV, LA, LD, LL, ML, NP, PA, PH, PL, SA, SY, TR, TQ and TD.
If your address is in one of these areas, we will contact you before processing your order to confirm any additional costs. We do not currently offer delivery outside the UK mainland.
What to expect on delivery day
- Deliveries are typically kerbside.
- Please ensure someone is on-site to accept delivery. For heavier items, help with offloading may be required.
- Many building materials arrive on large vehicles. If access is restricted, a specialist vehicle such as a HIAB may be required and could incur an additional charge.
Why delivery can cost more than typical parcel delivery
Building materials often travel on larger vehicles and usually carry fewer drops per run than parcel networks. That is why delivery charges can be higher than standard e-commerce shipping.
Returns
Returns depend on what you have bought and whether there is anything wrong with it. For full details on eligibility, timeframes, and exclusions, please see our full policy.
Customer Reviews
Used in a partition wall and worked well. One of the best thinner solutions for insulation!
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