Xtratherm Insulation Board

(24 Products)

Xtratherm Insulation Board is a high-quality insulation product designed to enhance the thermal efficiency of buildings with a certified thermal conductivity as low as 0.022 W/mK. It is made from a rigid polyisocyanurate (PIR) foam core, which is sandwiched between two layers of low-emissivity aluminium foil facings. This unique composition enables Xtratherm Insulation Board to deliver exceptional thermal insulation performance while also providing effective moisture resistance.

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What Is Xtratherm Insulation Board? 

In the quest for energy efficiency and sustainable construction practices, Xtratherm Insulation Board stands out as a reliable solution for achieving superior thermal performance in buildings. 

Manufactured by Xtratherm (now rebranded "Unilin Insulation"), a renowned industry leader, this insulation board offers exceptional benefits to homeowners, architects, and builders alike.

Xtratherm PIR Insulation Board - Key Features

  • High performance foil faced Polyisocyanurate (PIR) insulation
  • Thermal Conductivity 0.022W/mK 
  • Achieves an A+ rating under the BRE Green Guide
  • Surface Spread Of Flame: Class 1
  • Certification: BBA certified
  • Can be used in floors, walls and roofs
  • Similar performance capabilities to the likes of Kingspan
  • Compressive Strength >150 (kPa)
  • Can be used in conjunction with other insulating materials 
  • Zero Ozone Depletion Potential


Xtratherm Applications 

  • Roof Insulation
  • Wall Insulation
  • Floor Insulation
  • Cavity Wall Insulation
  • Flat Roof Insulation
  • Pitched Roof Insulation
  • Timber Frame Construction
  • Attic Insulation
  • External Wall Insulation (EWI)
  • Retrofitting Insulation


Xtratherm CavityTherm 

Xtratherm CavityTherm is a specific product offered by the insulation manufacturer Xtratherm, now known as Unilin Insulation. 

CavityTherm is a type of high-performance insulation board designed specifically for cavity wall applications in buildings.

Xtratherm CavityTherm boards are made from rigid polyisocyanurate (PIR) foam, a type of high-density insulation material known for its excellent thermal efficiency. 

These boards are specially engineered to fit within the cavity space of the wall, providing an effective thermal barrier.

Xtratherm Thin R Boards

As the name suggests, Xtratherm Thin-R boards are characterised by their slim profile and therefore low thickness. 

These strict dimensional tolerances allow them to be easily installed in areas with limited space with minimal intrusion.  This ensures you can make the most of valuable living space. It also makes them ideal for applications such as refurbishments, renovations, and insulation upgrades where maintaining existing building dimensions is crucial.

The closed-cell structure and gas-tight facings of the board provide excellent thermal performance and moisture resistance.


These boards are typically used above and between roof timbers to maintain a temperature close to that of the building's interior. 

Insulating above and between the roof timbers ensures consistent internal environmental conditions, thereby reducing thermal stress and the risk of condensation. 

Xtratherm Boards Storage 

Correct storage of Xtratherm insulation boards is crucial to maintain their quality and effectiveness. Here are some guidelines on how to store Xtratherm insulation boards:

  • Protect from Moisture: Insulation boards should be stored in a dry, well-ventilated area to prevent moisture absorption. Moisture can compromise the integrity of the boards and reduce their insulating properties. Store the boards in a location that is protected from rain, leaks, and excessive humidity.
  • Avoid Direct Sunlight: Prolonged exposure to direct sunlight can cause damage to the insulation boards. Store them in a shaded area or cover them with a light-coloured tarp or protective sheet to shield them from UV radiation.
  • Keep Elevated: Store the insulation boards off the ground to protect them from potential water or moisture on the floor. Use pallets, raised platforms or a similar flat surface to elevate the boards, ensuring proper air circulation underneath.
  • Stack Properly: When stacking the insulation boards, ensure they are placed vertically and evenly to prevent warping or deformation. Avoid excessive pressure or uneven weight distribution on top of the boards.
  • Handle with Care: During storage, handle the boards with care to avoid any impact or damage that could affect their performance. Avoid dragging or dropping them, as this can cause fractures or breakage.
  • Maintain Room Temperature: It is recommended to store Xtratherm insulation boards in an area with a stable room temperature. Extreme temperature fluctuations can affect the boards' structural integrity and may lead to dimensional changes.
  • Follow Manufacturer's Recommendations: Always refer to the manufacturer's guidelines and instructions for specific storage recommendations. They may provide additional instructions based on the particular type of insulation board you have.

Frequently Asked Xtratherm Insulation Board Questions

Why Did Xtratherm Undergo a Rebranding?

Xtratherm underwent a rebranding to align its identity with the Unilin Group. 

The rebranding was part of a strategic decision to integrate Xtratherm into the Unilin brand family and take advantage of the global recognition and reputation that Unilin holds in the construction and building materials industry.

Will The Product Names and Specifications Change with the Rebranding?

The product names may undergo some changes to align with the Unilin branding, but the specifications and performance characteristics of Xtratherm insulation products remain consistent. 

Any modifications will be communicated clearly to customers, ensuring a smooth transition.


How Should Xtratherm Insulation Board Be Installed? 

Proper installation is crucial for the optimal performance of Xtratherm Insulation Board. It should be installed according to the manufacturer's guidelines, which may include considerations such as appropriate fixings, sealing joints, and ensuring a continuous insulation layer. 


It is recommended to consult the installation instructions or seek professional advice for specific applications.

Are Xtratherm Insulation Boards Environmentally Friendly? 

Xtratherm insulation boards are manufactured using a blowing agent with zero ozone depletion potential and low global warming potential, making them environmentally friendly.

What Can I Use To Cut Xtratherm Insulation Boards? 

We recommend using either a sharp knife or fine toothed saw.

What Areas Of The Home Should Be Insulated?

The key areas you should target when tackling home insulation are the roof, loft and exterior walls. 


Since heat rises, your roof and loft are the biggest heat-loss culprits. And as a third of all heat lost from an uninsulated house leaks out through the walls, wall insulation is also crucial when it comes to preventing heat loss and adding comfort to a living space. 


The aim of thermal insulation is to create a thermal envelope around a building so it uses less energy. It's essentially like wrapping a big scarf around the walls and popping a woolly hat on the roof to keep the warmth in. 

What Are My Options When Choosing Insulation?

The insulation market is brimming with choices; with fibreglass, rock mineral wool, foam, and so many more products to choose from. 

There are a few things to factor in before making an insulation purchase: 

  • Thermal performance
  • Fire safety
  • Resistance to moisture
  • Cost
  • Durability


Choosing the right insulation product to suit your project is vitally important, we have insulation material for commercial and domestic projects. Please note you should always get professional insulation industry advice before installing insulation.

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