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37 Reviews
View Product Reviews100mm Celotex GA4100 PIR Insulation Board 2400mm x 1200mm
| 6+ boards | 12+ boards | 20+ boards |
| £26.84ex. VAT | £26.57ex. VAT | £26.02ex. VAT |
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Mon 22 Sep
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- 7hrs
- 27mins
- 48secs
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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, 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: | 100mm |
| Width: | 1200mm |
| Length: | 2400mm |
| Sales Unit: | Board |
| Sales Unit Coverage: | 2.88m2 |
| Brand: | Celotex |
| Manufacturer's Reference: | GA4100 |
| Weight: | 11.95kg |
| Thermal Conductivity: | 0.022W/mK |
Technical Downloads
Product Overview
Foil-faced PIR insulation board, measuring 100mm in thickness for use in floors, walls, and roofs.
Manufactured as part of the GA4000 range, it is intended for general application, meaning it can be confidently specified across a broad spectrum of build-ups without the need for specialist products.
The board consists of a rigid polyisocyanurate (PIR) core faced with low-emissivity foil on both sides. This construction provides excellent thermal resistance, helping to reduce heat loss through the building fabric while also acting as a vapour control layer.
At 100mm thick, the most widely used thickness in the GA range, it is sized to fit most standard cavities and joist depths, making it straightforward to integrate into typical construction details.
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.
- GA4000 range (general application): Suitable for versatile use across 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 × 1200mm: Supplied in the industry-standard sheet size for insulation, ensuring compatibility across typical build-ups.
- Thickness 100mm: Popular and practical size for achieving strong thermal performance in standard build-ups.
Applications
- General insulation: Versatile board suitable for a wide range of domestic and commercial applications.
- 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
Friendly customer service team to help me with my order
Celotex is my first choice PIR board. Price and delivery times from Materials Market was great, thanks.
Part of a summerhouse I built. I found them really easy to cut to fit into walls and then they slotted in nicely with some insulation tape to keep them in places and ensure there we no gaps anywhere.
5-star insulation and a 5-star service
Great product. You decent get coverage with each board and they are so lightweight, making them easy to transport around the building. Materials Market customer service was fantastic as well.
I used this in a suspended floor at home. It took a bit of time for me to fully install, but the boards are simple to cut and slide relatively easily in-between the beams. It's a good product and I'd recommend it.
Great board and great service. I'll buy again
Good product for the job
Managed to get a good rate after I spoke with someone over the phone
Not the first time I've this from these guys, and won't be the last. Spot on every time.
Boards are lightweight to move around the job
Used this under some floorboards, simple to handle and install.
Managed to grab this at a good price compared to other websites
I used this in my roof rafters ahead of the winter
The delivery driver was really nice when he dropped the boards off
5 star product. Service was great as well
Excellent service and board
Came as expected and easier to cut with a hand saw than I first thought
On time and customer service was good to help resolve a small issue
Top service. The boards came on time for my project
light and simple insulation to work with
Used this is in a partition wall and found them easy to cut. Delivered quick, with a cheap price
arrived as described and expected
These easily slid in under the boards of my ground floors
Thanks - came on time for my work
I bought these for a big timber framed floor system job, arrived on time and the customer service team were really helpful.
Great product, easy to work with and meet all national building regulations
Simple to install in the timber rafters for my loft conversion
Competitive price, fast delivery, and good quality product. Great insulation.
Used this product between timber joists and timber rafters and it worked wonderfully. Loft is now incredibly toasty. Shipping costs were free after £500 spend.
So cheap! Much cheaper than getting it at my local Travis Perkins
My rooms were warmer after I installed the insulation
My rooms were warmer after I installed the insulation
Easy to install and manoeuvre
Easy to cut and fit into walls
Excellent insulation!
Used in steel framed systems. Great insulation board!
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