The world's friendliest insulation.
At Sisalwool, we want to make insulation better. We are based in Roslin, Scotland, and are part of the Verified B Corp Sisaltech Ltd. We make natural fibre insulation from wool and recycled sisal. Our products help your space breathe, feel comfortable, and lower your carbon footprint.
Made for the person living in it, specified by the person building it.
Whichever side of the wall you're on, Sisalwool has to earn its place. Here's what each side gets.
A cosier, quieter home
Every slab and roll is made from the same natural fibre blend. Wool adds loft and softness, while sisal gives structure and strength.
- Gloves and protective gear are optional — it's pleasant to work with
- Free from harmful irritants and chemicals, safe near living spaces
- £5 sample box lets you feel it before it's in your walls
Order the sample box
Try before you buy! Feel the fibre, see the texture, decide with confidence. £5, delivered by courier.
Get the Sample BoxQuick to fit, hard to fault
Sisalwool is easy to install, safe to handle, and delivers reliable performance. It helps you meet deadlines, avoid callbacks, and cut materials with confidence. You can also reuse off-cuts on site, which is not possible with PIR.
- Friction-fits between rafters, ceiling joists, floor joists and studwork
- Class A / Class B fire and sound ratings, backed by datasheets
- Trade rates and pallet pricing. Call to discuss your project
Discuss trade rates
Call the team directly for pallet pricing, datasheets and delivery timelines for your site.
Call 0131 510 9296The four everyone starts with.
Every slab and roll is made from the same natural fibre blend. Wool adds loft and softness, while sisal provides structure and strength.
Sisalwool 50
50mm slabs for walls, floors and roofs. Friction-fitted between timbers — no adhesive, no suits, easy to cut with a saw.
Sisalwool 100
The thicker slab, built for acoustic and thermal performance side by side. The one architects specify most often.
Sisalwool Loftroll
Vegan, fully recycled loft roll made with sisal, cotton and reclaimed denim offcuts — the source of its distinctive blue.
Sample Box
Try before you buy. A hands-on swatch of the fibre and texture, delivered by courier — the easiest way to start.
How it actually gets installed.
This sequence comes from real retrofit and new-build projects. Installers use these steps whether they are working on a stone cottage or a garden room.
Strip back & assess
Existing plasterboard, old insulation or wall finishes come off. The structure is checked for damp, leaks or damage before anything goes back in.
Frame it out
A stud frame goes up against walls, or the existing rafters, ceiling joists and floor joists are used as the cavity.
Friction-fit the slabs
Sisalwool is pressed snugly into place by hand there is no adhesive, no specialist tools, cut to size with a standard insulation saw.
Seal & finish
An airtight vapour control layer goes over the top, finished with plasterboard. Wood-fibre board is often added as an over-sheet to cut thermal bridging.
Why natural fibre works harder.
Inspired by how nature can be both strong and gentle at the same time. Here is what that looks like in practice.
Ultimate breathability
Vapour-permeable by nature, so moisture moves through the building fabric instead of getting trapped behind stone or plasterboard.
Class A sound absorber
100mm slabs carry a Class A acoustic rating, absorbing 90–100% of sound energy. 50mm slabs are Class B.
Self-extinguishing
Passed the Euro class E reaction to fire test. When a direct flame is removed, Sisalwool self-extinguishes rather than melting.
Moth & pest resistant
A biodegradable, long-lasting insect deterrent makes the wool unpalatable to moth larvae there is no synthetic treatments required.
What it looks like on real jobs.
A few of the retrofits and new builds Sisalwool has gone into, drawn from our published case studies.
A traditional stone cottage, made breathable
Asset Integrity Scotland retrofit older stone buildings without forcing modern, closed-cell materials into them. Walls were stripped to bare stone, restudded, and friction-fitted with Sisalwool; roof and floor followed to full depth.
"This is the future of insulation."
A listed granite home, paired with a heat pump
A family-owned granite period home swapped its gas boiler for an air-source heat pump. MW Clubb specified Sisalwool for its breathability around solid granite walls — studs, floor joists and loft, stonework preserved throughout.
Their largest garden room yet — and their last with PIR
Green Space Dunbar build eco-conscious garden rooms. On their biggest build to date, Sisalwool 100 fully filled 4x2 timber studs across walls and roof, finished internally with marine ply.
"Easier, cleaner and faster to work with."
Rated 5.0 out of 5 from 9 verified customer reviews.
Order a sample, or call about trade rates.
Homeowners can try the £5 sample box first. Contractors get pallet pricing and technical guides with a call. Either way, the team picks up the phone.