Best option for roof insulation (and other insulation tips?)

[fieldfare]

Hi folks, we have a 2 up 2 down , 150+year stone cottage with rubble filled walls on a windy, south facing hill. Any thoughts on the 'best' roof insulation to use (most insulating, cheapest, greenest). How much depth would I need? Apart from draught excluders on windows and doors are there any tricks for increasing the insulation properties of such a pad?

cheers,

 

[Nemesis]

Not the cheapest but certainly has many benefits... Thermafleece.

 

[Gervase]

Glass wool/rockwool and the like are unpleasant to handle, but at least their manufacture is greener than the petrochemical-based materials like Celotex, Kingspan and the dubious foils. All they are, essentially, is sand that's been heated and spun like candy-floss.
That said. Thermofleece is far nicer to work with (if something like 10 times the price!).
It's also worth looking at Warmcel, made from cellulose, and Isonat, from hemp. All of which are green and can comply with the new Part L building regs.

 

[geoff]

I have a 200 yr old rubble stone wall house as well, whose roof (sloping ceilings in bedrooms to ridge height) I insulated some 5-6yrs ago and I looked at as many options as possible.

Thermafleece does seem to be extremely expensive - payback time will be very long.

I looked at Warmcel - there weren't many firms who could spray it and the one I found was condescending and bloody rude and basically had the attitude "I don't need the work now, so f*** off". The quote was also very high in comparison to anything else (many thousand for a smallish 2 bed house ). I didn't think the 'U' values of Warmcel installations (as quoted to me) were that high either - it seems to trade on it's 'green' recycling manufacture rather than its efficiency.

I ended up using the double foil blown foam Kingspan. I know the manufacturing arguments against it, but they seem a trifle exagerrated given the ultimate efficiency and cost effective, relatively easy fitting (cut to shape with a knife or saw). Low payback period. I fully filled the rafter depth (with tyvek breather membrane and double battened exterior for ventilation) and I have found the result is very good - even in very cold conditions the upper rooms can remain warm. The only problem is condensation on the skylights because they are substantially the coldest areas.

You will have to weigh up what suits your conscience, your pocket and your roof structure. I would go for the Kingspan/Celotex type again in the future - between the rafters as deep as possible (with a 50mm gap if conventional non breathing felt/slate structure), and a layer on the underside as well as deep as possible to avoid cold bridges.

 

[biffvernon]

Sheepswool or hemp (suitable for vegans) are certainly the greenest. Whether they are the cheapest depends on the price you put on the planet.

 

[Nemesis]

This is Thermafleece - the raw material - pic by me, Lake District, Sept 2006.

Thermafleece has given sheep like this a future. Beatrix Potter would be pleased.

No contest as far as I'm concerned.

 

[worms]

Nice picture. I notice that sheep has already had its fleece taken...do you travel around collecting your own insulation from the roadside?

 

[Lime]

Thermafleece has given sheep like this a future

It is also true that sheep have changed the landscape by grazing more than anything else.
Just look at the hillside.
Whether it is for the better is an arguable point, in a great many situations I think not.
After all, they did to Scotland what the English failed to do for centuries.

 

[Nemesis]

I think if the Lake District reverted to scrub it would be a very different place, not the landscape which is so familiar. I also think the cold for long periods has a great deal to do with a lack of vegetation, allied to not a lot of soil cover.

Other areas not grazed are covered in bracken. In fact hill farming isn't very intensive in the Lakes - it doesn't pay. The traditional way of management by hefting (or heafing) sheep though is fascinating stuff.

However - no I didn't manage to catch that one for insulation, although it's a thought... it's so unusual to catch sight of one newly shorn, couldn't resist a happy snap.

http://www.secondnatureuk.com/info.htm

 

[Penners]

This is Thermafleece - the raw material - pic by me, Lake District, Sept 2006.

Aaaaah - wook adda widdle fwuffy wamb.

Insulation on the outside, Sunday lunch on the inside. Nature's miracle.

 

[MDE]

Regardless of the pros and cons of sheep farming, Thermafleece is MUCH nicer to work with than Rockwool. Interestingly, when I contacted the suppliers recently about insulating a sloping roof, they suggested a combination of Thermafleece between the spars and Lafarge Thermalcheck board for the ceiling.
BTW, I don't think sheep eat bracken: only cattle keep the bracken down (by tramping over it). How about some leather draught excluders?

 

[Lime]

Sheep prefer plants that are young and tender and will graze close to the ground so mature wooden plants are left alone.
However even bracken starts off young and tender.
Look at the picture. The only tree is in a position where sheep cannot graze it.

 

[Nemesis]

It was a lovely day. I thought it a good picture. It was at the top of one of the passes, I don't think many trees really would grow too lush and straight there anyhow.

I don't give a bugger what Lime or anyone else thinks about sheep and the Lakes - I like them there, without the Herdwicks it wouldn't be the same.

It's good to see them hanging on in there, after the horrors of foot and mouth.

Bracken harbours sheep ticks though.

http://images.google.co.uk/imgres?imgurl=http://www.wordsworthcountry.com/sitepics/herdwick3-200.jpg&imgrefurl=http://www.wordsworthcountry.com/herdwick-sheep.htm&h=150&w=200&sz=6&hl=en&start=40&tbnid=-2u5aVGuqtW6eM:&tbnh=78&tbnw=104&prev=/images%3Fq%3DHerdwick%26start%3D20%26ndsp%3D20%26svnum%3D10%26hl%3Den%26lr%3D%26sa%3DN

Bit of a long link - but good info.

 

[Lime]

I don't give a bugger what Lime or anyone else thinks about sheep and the Lakes

I don't give a bugger for what you think either.

XXX

 

[Nemesis]

OK.

But Herdwicks have been a feature of lakeland life for a considerable time, and my life would be less rich without their presence.

Mrs Heelis was a great fan, and her work to preserve so much of what we know as 'the lakes' included the preservation of such a rare breed.


Forget the recent kitsch movie - this country owes Beatrix Potter a huge debt of gratitude for preserving buildings, traditional landscape and a rare breed. I hope the WHS bid succeeds.

http://www.lake-district.gov.uk/index/looking_after/projects/whs.htm

http://www.visitcumbria.com/bpotter.htm

 

[Pford75]

Very interested in this thread as now that our rewiring is complete and our cluster fly infestation dealt with we will be moving to insulation in the New Year.

We had investigated Thermafleece, but TBH it is way beyond our budget. The quote for Rockwool insulation (to be fitted by the supplier) was £3485 + VAT...whereas the Rockwool alone (without fitting) was coming in at something close to £25000!!!!!

If I add in the fact that the Rockwool insulators reckon on 2 guys for 2 days to clear the loft and insulate....the Thermafleece does look a little pricey!

So, am I missing something here? Are there any unspeakable implications of rockwool (bearing in mind I won't be laying it)? Is the insulation value of thermafleece a lot better? We're pretty eco friendly (gray water recycling, composting etc.) but this is a little hard to justify.

Are these prices way out? Is there a possibility i'm just being 'fleeced' (sorry) by the supplier?

 

[joatex]

Geoff did you fit the double foil blown foam Kingspan insulation from above by removing tiles or whatever? Or fit from below removing the existing ceiling?

 

[Penners]

sheep and the Lakes - I like them

Me too. I remember having to go on a business trip to the Lake District during the height of the foot-and-mouth. The hillsides were completely devoid of sheep - it was awful.

 

[Nemesis]

The whole of the Eden Valley was simply eerie... empty fields, apart from every now and again there was a funeral pyre or the army removing dead animals neatly laid out in rows, The new born lambs were the most heart breaking sight. There was very real concern for the Herdwicks as it was considered they may all have to be slughtered, although there is a small flock kept in Scotland just in case.

The thing that the words 'foot and mouth' alwys brings back is the smell of burning, which seemed to be permanent.

The last but one herd of dairy cows to go was the one along the road from us. They hadn't any disease, the farmer had possibly had sonme contact with someone who had had contact etc... I knew those cows well, sat many a time behind them as they shambled along the road for milking.

Every morning I loked out of the window hoping the sheep on the fell opposite were still there - thankfully they survived. I think few people realise how cut off farming families became, unable or unwilling to leave the land. Local children couldn't go to school, those preparing for A levels were especially badly hit.


Rockwool... no I don't know much about it, it possibly is better than some forms of insulation, and I agree wool insulation is very expenisve, especially for a large area, although I think it has other benefits such as breathability.

It gives some use for the fleeces of sheep which otherwise were simply becoming unviable.

 

[Gervase]

To be honest, the nastiest thing about rockwool and other silica fibres is handling the stuff. If you've got contractors to do that for you, then I wouldn't worry. In a perfect world we'd all have Thermafleece and cellulose insulation, but it is still rather a luxury for those of us on tight budgets.