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Warmshell Woodfibre Boards

Warmshell Woodfibre boards are the intelligent insulation option which can buffer and store heat and moisture, keeping you warm and dry in winter and stopping overheating in summer.  Warmshell wood fibre won’t trap moisture because they are highly breathable and exploit woods incredible ability to wick and harmlessly move water. Made with waste sawdust from sustainable FSC accredited forests, they are the sustainable, low carbon option for internal and external wall insulation. And unlike some insulations, our boards are totally free from formaldehyde and other biocides.

Compared to lightweight synthetic insulations, the density of Warmshell woodfibre allows phase-shift  to reduce summer overheating  as well as giving excellent sound deadening acoustic properties.  Warmshell doesn’t just save heat, it creates a comfortable, healthy indoor climate.

The boards can be used as part of our wall insulation system with Internal Plasters, or External Renders, which is available with detailed guidance, system warranties and installation information. Warmshell Woodfibre boards can be used with our systems to achieve Class B for Reaction to Fire on walls.


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Data Sheet

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datasheet (XL)

Our wood fibre insulation boards are made in Europe to the highest standards, and independently certified for FSC and quality. These sustainable boards exploit wood's natural properties to give insulation that is strong, warm, tough and safe to work and live with. The Warmshell woodfibre board is a universal all-purpose board, suitable for insulating both the internal or external side of walls, on roofs and is commonly used on both timber frame and masonry. Wood fibre is over 95% sustainable wood shavings and dust, with each board actually locking up more carbon than is released as it is made.

Woodfibre is Warm

Wood fibre boards are as warm as many synthetic insulations such as Expanded Polystyrene (EPS) or rock or glass wool, with a thermal conductivity of k=0.040 or 0.44. But unlike most insulations, they have much higher thermal mass, helping store heat and even out spikes in temperature, leaving your walls warm and cosy. The tongue and groove profile and direct application also means Warmshell wood fibre can achieve good levels of air-tightness

Woodfibre for Moisture Control

Wood has evolved to store and transport moisture - almost nothing else does it as well. Unlike synthetic insulation, which can trap moisture or wet-out easily, woodfibre can buffer large amounts of moisture without suffering from rot or mould, allowing it to wick away and evaporate harmlessly. This ability to store or move moisture makes wood fibre a dynamic, intelligent insulation, out performing synthetic plastic insulations such as insulated plasterboard. Used as part of our highly breathable Warmshell Internal IWI system, Warmshell Woodfibre can help avoid problems like mouldy window reveals and rotten timber joists.

Woodfibre is Healthy

Wood fibre is safer to live with, as it doesn't require biocides or create high levels of indoor pollutants through off-gassing. By managing the moisture in the walls, it also creates a more healthy indoor climate. Disposal of off cuts and waste is also much easier, as our Warmshell woodfibre is over 95% wood. Woodfibre also helps with phase-shift; in a roof or other lightweight structure it will keep the inside considerably cooler during heat waves compared to lightweight insulation, for much greater comfort when you're too hot to sleep at night.

 Woodfibre is Durable

Timber structures in the UK survive that are hundreds of years old. By working with nature and physics exceptionally durable structures can be built using wood fibre - rather than relying on plastic membranes and biocides to try and defeat moisture and rot, you can avoid creating the conditions for it in the first place. Warmshell External , our EWI system with wood fibre and render, has been tested for 25 years of accelerated freeze thaw without peeling, cracking or de-bonding.