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Celotex GA4000 PIR Insulation Board 2400x1200x100mm
High-performance PIR insulation board with 0.022 W/mK thermal conductivity for walls, floors, and roofs.
- Thermal conductivity of 0.022 W/mK
- Foil-faced both sides
- 100mm thickness
- BBA certified
Overview
The Celotex GA4000 is a rigid PIR insulation board used across UK construction.
In-Depth Look
The Celotex GA4000 is one of the most widely specified PIR insulation boards in UK construction. It is used in floors, walls, and roofs across both new build and retrofit applications, and is a familiar product for builders working to current Building Regulations energy performance requirements.
PIR Thermal Performance
PIR (polyisocyanurate) foam achieves a thermal conductivity of 0.022 W/mK — significantly better than mineral wool at 0.032–0.044 W/mK and EPS at 0.033–0.038 W/mK. This means a given U-value target can be achieved with a thinner board, which is important in floors and wall cavities where thickness is constrained by structure or headroom. The 100mm GA4000 board achieves an R-value of approximately 4.55 m²K/W, making it suitable for achieving the U-values required under current Building Regulations Part L for walls, floors, and flat roofs.
Application Scope
The GA4000 is a general-purpose board designed for ground floor slab insulation, warm flat roofs, inverted roofs, cavity walls, and internal wall insulation. The foil facing on both sides reduces radiant heat transfer and contributes a partial vapour resistance. For specialist applications such as external wall insulation systems, Celotex produce application-specific products with appropriate facing and declared performance values.
BBA Certification
The GA4000 carries British Board of Agrément (BBA) certification, confirming independent assessment of performance and durability in use. BBA certification is accepted by building control bodies including LABC and NHBC for Building Regulations compliance sign-off, and is required by many architects and specifiers when approving insulation products for new build and refurbishment projects.
Cutting and Handling
PIR boards should be cut using a fine-tooth handsaw or by scoring and snapping. The foil facing should be scored first to prevent delamination. Wear appropriate dust PPE when cutting — the foam produces fine particles.
Verdict
The go-to PIR insulation board for UK construction. Excellent thermal performance, BBA certification, and wide availability from builders’ merchants make it the default specification across most application types.
| Dimensions | 2400 x 1200 x 100mm |
|---|---|
| Thermal Conductivity | 0.022 W/mK |
| Core Material | Polyisocyanurate (PIR) |
Who It's For
- Builders and contractors
- Self-builders working to Building Regulations
Pros & Cons
Pros
- Excellent thermal performance
- Thinner than mineral wool for equivalent R-value
- BBA certified
Cons
- More expensive per m2 than mineral wool
- Requires careful cutting
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