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Celotex XR4000 Insulation Boards

(7 Products)

Celotex Insulation XR4000 is the code Celotex gives their multi-purpose 'Extra Resistance' insulation boards; in sizes thicker than 100mm. The 2.4m x 1.2m boards have zero ozone depletion potential (zero ODP) and low global warming potential (GWP) and boast a PIR foam core sandwiched between two low emissivity foil facings. With a thermal conductivity of just 0.022 W/m.K, the boards are suitable for use in a number of applications including roof, wall and floor systems.

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What Is Celotex XR4000? 

The Celotex XR4000 distinguishes itself by being the thickest insulation offering within the Celotex product range. 

Its substantial thickness not only underscores its robustness but also its enhanced capacity to retain heat, making it an optimal choice for those seeking maximum thermal insulation efficiency in their projects.

Celotex XR4000 is a multi-purpose insulation board employed in scenarios where a more substantial thickness is necessary to achieve the desired thermal insulation levels, or "U-values."

Celotex XR4000 is targeted at ‘cut-to-fit’ applications between rafters or joists and enables users to achieve lower U-values with a single layer of insulation. 

Where Is Celotex XR4000 Used? 

  • Pitched roofs
  • Solid masonry walls
  • Timber framed & steel framed systems
  • Floors


XR4000 Benefits 

  • Superior Insulation Efficiency: These panels are engineered to deliver high insulation performance with a low thermal conductivity rate of 0.022 W/m.K. This efficiency means you can use less material to meet or exceed specific insulation standards, leading to potential cost savings and enhanced energy efficiency.
  • Flexible Use: Designed for adaptability, the XR4000 can be applied in numerous building scenarios, including different types of roofs, walls, and flooring systems. Its utility across multiple structural frameworks makes it a go-to solution for comprehensive insulation coverage.
  • Eco-Friendly: The production process for these insulation boards includes the use of materials that have minimal impact on ozone depletion and global warming, showcasing the manufacturer's commitment to environmental sustainability.
  • Installation Convenience: The physical properties of these boards, such as their light weight and rigidity, facilitate easier handling, transport, and installation, streamlining the construction process.
  • Quality Assurance: The XR4000's performance and reliability are validated by its BBA certification, indicating its suitability for specified insulation tasks as per established standards.
  • Variety in Thickness Options: With thicknesses available from 110mm to 165mm, the product range offers flexibility to achieve desired insulation levels without necessitating the layering of materials, enhancing both efficiency and effectiveness.
  • High-Performance Facers: The inclusion of low emissivity foil facings on these boards significantly boosts their thermal performance in air cavities, optimising the insulation's overall effectiveness.


XR4000 Fire Classification

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.


XR4000 Thicknesses


Frequently Asked Celotex XR4000 Questions

Can Celotex XR4000 Be Used in All Types of Buildings?

While Celotex XR4000 is versatile and suitable for a wide range of applications, it's important to note that it should not be used in the external walls of buildings over 11 meters in height. 

This is due to fire safety regulations that require non-combustible or limited combustibility materials in such applications.

How Does Celotex XR4000 Improve Thermal Performance?

The low emissivity foil facings on both sides of the XR4000 board enhance thermal performance within cavity air spaces, effectively reducing the U-value and improving the insulation's overall efficiency.


Is Celotex XR4000 Easy to Install?

Yes, the boards are lightweight and rigid, which facilitates easy handling, transportation, and installation. Their design assists in quick fitting and securing in place, making them a convenient option for contractors.

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