Earthwool 'carbon zero' loft insulation

[David WE Roberts]

How good is this stuff?

Nice that it is made from fluffy baa lambs not nasty itchy glass but is it an equivalent insulator?

Homebase have it on offer for 49p/square metre on 10% day. Next cheapest is 100mm Space Combi made from recycled glass bottles at

61p/square metre.

The 100mm space blanket is £1.49/square metre and the 200mm £3.49/square metre (do a quick sum and but 2 * 100mm rolls instead of 200mm rolls!).

I am looking at various insulation strategies for TMOALS (The Mother Of All Sheds) and just got the HomeBase flyer in the mail.

What also puzzles me is how it is cheaper to process wool from sheep than to blast out thin glass fibres on a production line.

What also puzzles me is why the price per 100mm thickness goes up with thicker rolls of insulation when you would think it should come down. For instance the 100mm Space Combi is 61p/square metre. Multiply by 1.7 gives £1.037. However toe 170mm roll is £1.07 per square metre.

About the same logic as pricing for different size packages in supermarkets, I suppose.

But I digress.

Should I consider the wool insulation?

Cheers

Dave R

[Dave Liquorice]

er a google kicked up

which says it's recycled glass bottles. U value 0.040W/mK.

There are real wool insulation materials available Thermafleece

which has U value 0.039W/mK

There is virtually no value if fleeces from sheep living on the fells. The wool is to coarse and rough for clothing. Some is used in carpets. The sheep have to shawn but it costs the farmer more for the sheep shearer than they get for the fleeces.

Look at the figures for U value and how much you get per =A3. The real sheeps wool stuff is far nicer to handle than the glass based stuff. Space blanket is wrapped in plastic but if your joists are not at the right spacing I can see that being a pain.

[sm_jamieson]

Its not sheeps wool, its glass fibre. I'm using some "earthwool" from Wickes at the moment to insulate a roof. It is made from something recycled and is quite dirty and dusty, not bright yellow like some of the stuff. However, it is cheap and just as good.

Its also cheap as its the end of a job lot at 170mm depth, earthwool is now only manufactured in 100mm and 200mm. I guess the recommended depth has gone up by 30mm !

Simon.

[terry]

Didn't we also hear of some insualtion made from 'recycled jeans' or summat?????? Also from recycled fire retarded newspaper etc.

[sm_jamieson]

You wouldn't have to do much extra shredding, judging by the sort of jeans worn by students etc. around my locality.

[Andy Dingley]

Not these days it isn't. The wool carpet trade for sheep (mostly Herdwick) has collapsed and their fleeces are worthless.

I've made thick felt for yurt covers out of them. Great fun! You need a big blue tarp, a giant swiss roll and a cricket bat.

Welsh sheep (fluffier) still have a market for fleece, AIUI.

[David WE Roberts]

er a google kicked up

which says it's recycled glass bottles. U value 0.040W/mK.

There are real wool insulation materials available Thermafleece

which has U value 0.039W/mK

Oh, bugger!

Felt a roll in the local store and it didn't feel like the usual stuff, and the flyer lists virtually everything else as made from recycled glass or plastic bottles so I assumed it was real wool :-(

So, not really much different from the other ones made from recycled glass.

[Alan J. Wylie]

Walking in Patterdale last summer there was a dreaful stench and pall of smoke from a local hill farmer burning his unsaleable fleeces.

[Tim Watts]

Alan J. Wylie wibbled on Wednesday 10 February 2010 19:03

That's pathetic. How much would it cost to wash and form the wool into insulation compared to the energy required to melt and spin old bottles?

Given a roll of sheeps wool insulation retails for a sensible amount, there must be a market. The ad angle is trivial - no more itchy-itchy, use our eco friendly sheeps wool to insulate your loft - look, here's a kid playing on a roll... Certainly have the DIY market sewn up if it can be retailed for a similar price to rockwool.

If there's a surplus of glass, use it as cullet - only needs breaking and grinding.

[Dave Liquorice]

Why, synthetics taking over? Not in this house, though I admit new carpets are a wool mix, they do wear better.

Agreed, a wonderful resource being wasted. Perhaps you ought to talk to the Wool Marketing Board, the only government post war marketing board that is still in existance. Farmers have virtually no choice but to sell to the board, who take their cut, before passing the price they get back for job lot auctions to the farmer.

[Dave Liquorice]

Earthwool no, except that from comments here it dusty and dirty before you fit it let alone after being in loft for a year or five...

Thermafleece is very nice to handle, I suspect it might still be a bit dusty but at least it won't get into your skin like glass fibre does.

[zaax]

sherly, wool is going to be attacked by the clothes moth?

[<me9]

Can't be anywhere near as bad as the roast pork stench in the early 2000's in the F&M outbreak. It's put me off pork possibly for life!

[Rick Hughes]

if you want a REALLY good insulation take a look at Warmcell .... I have

450mm deep in my loft and 150mm deep in all walls.

Sprays in damp, and sets to consistency of a Madeira cake ...( incredibly sound absorbing as well)

It's re-cycled newsprint and totally fireproof ...

[Dave Liquorice]

Quite, we were a good ten miles down wind of the pyres in the Eden valley and the smell from the pyres was very noticeable. Have a photo somewhere taken from Hartside Cafe, the number of smoke plumes really shows what happened.

[The Natural Philosopher]

Mice love it as well

[Tim Watts]

The Natural Philosopher wibbled on Thursday 11 February 2010 10:13

The little buggers love glass wool too. The only difference is glass does have some negative feedback (kills them). It is a good point though - but give me sheeps wool or celotex anyday; I'm still getting itchy fixing the joists upstairs and I already removed the manky glass wool and crap and hoovered some months ago...

[Clive George]

Yebbut mice love anything.

[Dave Liquorice]

It is treated with a non volatile insecticide. Thermafleece is BBA approved so that shouldn't be an issue.

They make nests in fibre glass as well. I guess they might actually eat a wool based insulation.