Sisalwool 50 - Natural Fibre Insulation

Designed with performance longevity in mind, Sisalwool 50 offers a smart balance of high quality and low carbon impact Made from 100% natural fibres and completely free from harmful chemicals or irritants, it’s gentle to handle, so gloves and protective gear are entirely optional. Installation is quick, clean, and simple. Our slabs are made to friction fit easily between rafters, ceiling joists, floor joists, and studwork, no messy adhesives, no awkward protective suits, and no fuss.

Thanks to its breathable natural composition, Sisalwool 50 supports healthy indoor air quality and is ideal for both new builds and retrofit projects. Each slab is crafted using upcycled materials like coffee sacks and industry off cuts that would otherwise go to waste, so you’re insulating your space and helping the planet.

Why chose Sisalwool?

• Breathable
  
• Easy friction fitted
  
• Class B sound absorption 
  
• Eco-friendly
  
• Thermal efficient
  
• Sustainable, low carbon product
  
• Anti-irritation
  
• Suitable for retrofit and new builds
  
• No harmful chemicals
  
• User friendly

FAQ

Is Sisalwool fire resistant?

Sisalwool successfully passed the Euro-class E (Reaction to Fire) surface spread of flame test, a classification. making it fully approved for use on non-boundary walls in buildings up to 18 meters high. In this test, a direct flame, like a lighter, is applied to the material. Once the flame was removed, Sisalwool self-extinguished, demonstrating its fire-resistant properties.

But in true Sisalwool fashion, we didn’t stop there. We went one step further. To prove just how robust Sisalwool is, we thought why not do the test again, but this time with a blow torch? The results speak for themselves. 

Watch the video here

How well does Sisalwool handle moisture?

Sisal fibres have a naturally breathable structure that allows vapour to pass through, helping regulate indoor humidity and reduce the risk of condensation or mould. Combined with wool’s ability to absorb and release up to 30% of its weight in moisture without feeling damp, Sisalwool insulation helps maintain healthy indoor environments - ideal for traditional buildings that need vapour openness and long-term stability.