Celotex XR4000 is an easy to install polyisocyanurate (PIR) insulation board with excellent thermal performance, featuring a low emissivity foil facing. Available in thicknesses from 110mm to 200mm, it can be considered for roof, wall and floor applications.
U-value CalculatorStart your U-value calculation >
- Lightweight 2400 x 1200mm boards
- Low emissivity foil facing
- Achieves a BRE Green Guide A rating
- BBA certified – certificates 16/5352 (Timber Frame Dwellings), 17/5405 (Pitched Roof, Dry Lining, Floor Insulation)
Euroclass F Reaction to Fire classification, according to BS EN 13501-1. Products with this level of classification are not provided with a rating for smoke emission.
|Thickness (mm)||Length (mm)||Width (mm)||Lambda Value (W/m.K)||R-Value (m².K/W)|
- Thermal Performance - Excellent thermal performance with a thermal conductivity of 0.022 W/m.K, reducing the thickness of insulation required to hit the target U-value.
- High Performance Facer - Low emissivity foil facing provides improved thermal performance in sealed cavity air spaces, improving the achievable U-value.
- Easy to Install - Celotex boards are light and rigid assisting with ease of transportation, handling and fitting.
- BBA Certified - Celotex XR4000 has been assessed by the BBA as fit for use in defined roof, wall and floor applications if installed, used and maintained as set out in the certificate. Please read the certification at insulation-UK.com/BBA for full details and restrictions.
- Sustainability - Celotex XR4000 achieves a BRE Green Guide Rating of A, which can assist in demonstrating environmental performance in your BREEAM assessments. Please visit the Celotex page at GreenBookLive.com for further details.
When using Celotex XR4000, you need to satisfy yourself that use of the product meets all relevant national Building Regulations and guidance as well as local, national and other applicable standards relevant for your construction or application, including requirements in relation to fire and applicable height restrictions.
Please refer to the following product documents:
Celotex XR4000 should not be used in the external walls of buildings over 18 metres in height (England and Wales) or 11 metres in height (Scotland). Recent changes to Building Regulations mean that only non-combustible insulation or insulation of limited combustibility can be used in buildings of that height.
Applications: Click here to discover applications
- Roofs - Pitched Roof Insulation - Loft Insulation
- Roofs - Pitched Roof Insulation - Between Rafters
- Roofs - Pitched Roof Insulation - Between and Under Rafters
- Roofs - Pitched Roof Insulation - Between and Over Rafters
- Roofs - Pitched Roof Insulation - Pitched Roof Sarking
- Roofs - Flat Roof Insulation - Balconies and Terraces
- Roofs - Flat Roof Insulation - Between and Under Joists
- Walls - External Wall Insulation - Timber Frame Walls
- Floors - Ground Floor - Beam and Block Floors
- Floors - Ground Floor Insulation - Concrete Slab Ground Floors
- Floors - Ground Floor Insulation - Upgrading Concrete Slab Floors
- Floors - Ground Floor Insulation - Suspended Timber Floors