Sheepswool - its green, clean, and breathable

We've been fighting for a long time to get sheepwool insulation accepted as the norm in this country. There are almost limitless reasons for using it, and no reasons we've found for NOT using it. All other forms of insulation are unhealthy at best, and toxic at worst. Recently we've seen the Grenfell enquiry start to unravel the toxic culture surrounding the certification of chemical insulation products like Celotex and Kingspan, and others.

First - The problems that have held it back: 

There have been problems - one product that has been marketed in this country called Thermafleece has seen repeated instances of bug infestation widely publicised, and as a reuslt there is now a severe stigma attached to sheepwool insulation - most people are afraid to use it, and fear they will end up with an expensive insect problem. This was a comment we saw on one forum:

"I missed the radio programme. I hope someone told in full how Second Nature have gone into liquidation but popped up again as Eden Renewables, how they delayed and denied the problem and went bust just after they received compensation from Defra, details of which they are apparently bound to keep secret. I am presently homeless as we are having to remove all the sheepswool from our walls and roof. It's a 16 week job and involves stripping our entire house back to first fix and is an environmental and financial catastrophe.

I am very sorry for other companies producing sheepswool insulation. I hope they don't get tarred with the same brush as the fallout continues."
This was the experience of folk on another forum:
Black Mountain Insulation used to operate in north wales, but went bust - they've now popped up again - their website has only a phone number and no address, no information about the people involved - but interestingly, there seem to be several chemical companies associated with them, under ownership of the same Director. I'm always suspect of anyone who won't talk about the people involved in the company, or the address they operate from. 
A secondary issue is that most, if not all producers have incorporated varying amounts of plastic / chemical fibre into the wool. I don't know of any products other than the Isolena product from Austria, that are pure wool. Even a small amount of polyester fibre, for example, is a fire hazard. There is even one insulation made entirely from shredded PET plastic bottles. You can imagine that little lot going up in smoke.  Sheepwool with such fibre is not just toxic, its a fire hazard.
So - you have to conclude from reading this lot that there is a problem - and clearly it needs to be addressed. In this country, there is little enthusiasm for the product as a result.

Second - The good news!

A lot of research has been done to find ways of getting around the problem of bug infestation. There are two basic ways:
Treat it with Borax (which is a toxic chemical known to induce hormonal problems, fertility issues, and mored. Its been banned at least in part by the EU. I'm not keen to suggest you buy wool treated in this way. Borax is applied by spraying a solution onto the wool - whereupon it dries and crystallises. When the wool is moved, the borax can then fall off, as it's a rigid crystallised material. Whether at some point someone comes up with a way of keeping it there, I have no idea - but it has failed in the past, is a known toxin, and aren't we trying to promote a nice healthy, chemical free alternative anyway?
The second possibility is a patented process developed in Europe which essentially flash heats the wool, slightly changing the protein structure so make it unappetising to bugs. Its marketed as 'Ionic Protect' and is Certified by the NaturePlus organisation in Europe. This wool is now marketed in the UK by Sheewoolinsulation - and all the wool sold is from British or Irish wool. I've been to their manufacturing premises in Austria, and it's an extraordinary place - recycling all of the heat generated in the manufacturing proces, generating their own electric power, and constantly researching ways to ensure that the wool is chemical free. It also refuses to burn. Hitting this stuff with a blowtorch just chars it. Its very hard, if not impossible to get it to burn.  I love the stuff. We have it here in the Heritage House Head Office, and it's never been bug affected. Everyone who has used it in our client database says it is lovely. We make nothing from this - I've bought all of the wool in HHQ - but I'm convinced it is a solution that works, and allows you to use pure wool insulation, without the spectre of any form of bug infestation.

And now the Parliamentary Problem

As you all know, insulation is being pushed heavily by the government as the solution to all evils. Clearly, we know that isn't the case. What we don't like is chemical insulation - and at the moment, all of the government schemes will ONLY allow chemical insulation products - due 100% to the immense lobbying power of those companies. What we are now trying to do is to have sheepwool insulation accepted as a product that can be installed as part of the energy upgrades currently being funded by government. To put pressure on Government to do this, we need to keep lobbying - there is now a petition asking the Govt to include sheepwool - you can find it here - PLEASE sign and help save Britains sheep farmers too - their wool is currently being ploughed back into the ground as it is unsellable.  Let's get rid of toxic, often highly flammable plastic products and promote sheepwool produced here, and green our homes - here's the link:

The 38 Degrees Petition to Government to use British Wool for British Insulation

So what are the advantages?


  • Wool insulation does not off-gas harmful chemicals.
  • Wool fibers serve as an air filter.
  • The amino acids in wool insulation bond with harmful chemicals such as formaldehyde, nitrogen oxide and sulphur dioxide on a molecular level.
  • Wool is hypo-allergenic – making it well-suited for those who are chemically sensitive.
  • The US EPA suggests that indoor air quality is 2-5x worse than outdoor.


  • Wool fibers manage moisture by absorbing and releasing moisture against 65% relative humidity.
  • Wool prevents condensation by generating heat from energy, making it warm when wet.
  • Moisture is inevitable; wool’s inherent management capabilities allow for longer lasting products.
  • Wool is a keratin and will not support the growth of mold.


  • Wool exceeds other forms of insulation as an acoustic buffer.
  • Sheep’s wool absorbs 90 & 95% of airborne sound.
  • Unique visco-elasctic properties of wool assist in the conversion of sound energy to heat
  • The fibrous nature of a wool fiber means that, unlike many other materials, wool products can reduce airborne sound, surface noise and sound transmission all at the same time.

This is why you need to support wool!  The BBC flame test - it is truly scarey;


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