Earth-sheltered building, Sheffield

[Jane Smith]

We're lucky enough to have an old (160-170 years old, I think) stable block which is built into the side of the hill. It needs a new roof, and is currently damp and unusable, but it's structurally sound apart from that.

We're considering extending the stables by building an earth-sheltered extension to the back of it, which will be separated from the existing building by an atrium. This should allow us to leave the existing building predominantly unchanged, while using it fully. It's too narrow to provide useful accommodation as it is and would have to be knocked about a lot to turn it into useable accommodation without this extension: and if we're to renovate it, rather than leaving it to decay, we have to be able to earn money to pay off the cost of that renovation.

As if this wasn't ambitious and expensive enough, we're entirely off-grid so the whole thing has to use power we can generate ourselves, and water we collect ourselves. We currently have a Proven 6kW wind turbine, which powers our house and heats it when it's really windy.

I'd welcome any comments, warnings and suggestions. And advice. Especially if anyone has any ideas about how we could fund this, apart from selling our children. Our aim is to eventually use the stables and extension as holiday accommodation, and as an educational facilty (that sounds pretentious, sorry) so that people can come and learn about the technology on which we depend.

So, to get started: has anyone built underground, or know of anyone who has? What were the drawbacks? And what's the most environmentally-safe way of doing this? (All the systems I've seen rely on huge amounts of concrete and I'd love an alternative).

 

[Jane Smith]

No one loves me, no one cares....

 

[piper]

They're having a row about Elvaston Castle. Wait till the dust settles, and try again.

 

[Nemesis]

Oh, I'm not having a row about it. It's beyond tedious now, although I don't mind playing with trolls for a while as they always show themselved up for what they are in the end.

This one

http://www.channel4.com/4homes/ontv/grand-designs/houses/C/cumbria.html

isn't far from us, but I agree - concrete seems to be used in vast amounts for these buildings.

 

[piper]

Actually, to be fair, the Elvaston Castle row is involving a very limited number of participants, not including the ones who would be most helpful to you. The rest are probably not looking at the Forum much, because we are so bored with the row.

 

[Nemesis]

Well it isn't really a row is it? That demands some heat, I'm not producing any. It has however made me delve further into the situation, when I was marginally aware of, of for reasons I won't go into here that's a useful thing.

I won't be joining in the outcry. Too many buildings in real danger, not enough time.

The good thing about a forum is, if you aren't interested in a thread there is some element of choice involved. Don't click on it, don't read it. There is no element of compulsion.

I suspect it's quiet as it's the weekend.

Re the house above:

'When you take into account the glass, the foam insulation and the massive amount of concrete, the materials for this house have been responsible for releasing 70 tons of carbon dioxide into the air – an eco-nightmare.
But now it's built, the house will be virtually self-sufficient. Photovoltaic tiles will generate much of the electricity that Helen and Phil will need. Waste will be dealt with organically by the reed-bed system. The house will cause no more carbon dioxide to be emitted.

Kevin McCloud has calculated that, as the average three-bedroom house produces 5–10 tons of 'greenhouse gas' a year, the eco-house will have paid back its carbon dioxide debt within 15 years. After that, it will be costing the earth nothing, and if the performance of photovoltaic tiles continues to improve, the house may eventually sell solar energy back to the grid.'

It may be worth ttalking to the architect - he may have other ideas now, although clearly there will always be some materials and methods of building which are unsuitable for this situation.

How are you intending to deal with the damp stable wall? We have a similar underground wall on our gig house. In the past it has been badly treated with modern methods of trying to prevent damp seeping throgh the rubble. It didn't work of course.

We are intending to do something about trying to remove the slurry that's on it as far as possible, and do the lath and dry lining solution, with vents at the bottom. It isn't so damp it would require a pumped system.

 

[Jane Smith]

The whole block is damp, for a few reasons:

It's built into the side of a hill, and while the hill has been dug out behind it, it's not been dug out deep enough and water pools in the dug out bit when ever it rains. The hill remains in place to the south end of the building, and that wall runs with water when there's rain around (and for days after, as the rainwater percolates through).

There is an old system of drains in place, which emerge from beneath the floors at the front of the building, but the old clay pipes have collapsed and to replace them we'd have to dig up a floor made from 8" thick stone slabs--no easy job, and we've been concentrating on the house.

Pieces of the stone floor have all ready been lifted, leaving the floor somewhat patchwork. The spaces show that the blocks have been laid directly onto soil, which is sodden, probably due to the collapsed drains.

As yet we have no specific plans for any of this work; but it's obvious that we need to make a lot of improvements to the drainage and ventillation in the stables if we want them to be dry and comfortable. Which will probably involve digging out a lot more of the hillside against which they have been built.

 

[Nemesis]

Ours has no drainage at all - it's simply partly undergound, and had an earth floor. Before the days of limecrete we laid a cement one, but the earth was actually very dry.

I suppose when built it was probably a little more resistant to damp, but as the years went on the mortar degraded which won't have helped. We did consider digging out behind and at the side, but I think possibly we may hit rock and too much else to do, too little time... and not enough cash!

 

[worms]

Since I think you've previously mentioned land as part of your property, your proposed renovation to form holiday accommmodation might have been eligible for support under the DEFRA Rural Enterprise Scheme. Unfortunately it closed to new applicants in the middle of 2006 and a replacement scheme is yet to be announced. I think any new scheme may be organised through your local Regional Development Agency and I am not sure if you need an agricultural holding number and evidence of an agricultural business. Worth checking out though, since some similar schemes have in the past got support of up to 40% of eligible costs! Others on here will hopefully know more about this.

 

[NT]

Huge amounts of concrete is the logical option, as it will need a lot of strength to stop a huge pile of earth from caving in. And concrete likes damp conditions. There are other concrete type mixes than sand cement & stone, but I'm not sure they'd save anything much.

Sometimes the walls etc have been dug as spaces in the soil, then all the walls poured in one go.


Anyway, you'll need to streamline your energy consumption, and it sounds like that wouldnt be too hard in your case. Solarthermal power for the TD would be a start.


NT

 

[Nemesis]

It's the sort of project the Ecology Building Society would lend money on also, whereas others may not be so keen.


More here about the house above:

http://www.buildingforafuture.co.uk/winter02/greenpro_insert.pdf

Here's another, and there's a link to the British Earth Sheltering Association too:


http://www.bbc.co.uk/wiltshire/villages/nettleton_underground_house.shtml

 

[Moo]

In my innocence I found the Elvaston Castle thread very interesting. One can learn a lot from eavesdropping on two knowledgeable people engaged in a heated discussion.

And at least it was couched in language I could understand - unlike those esoteric threads about electrical things.

 

[Nemesis]

One knowledegeable person Moo - me. The other really hadn't a clue, and I do know a great deal about the situation. It's easy to pull a few 'facts' from a website and make it sound as though you have some idea when you haven't.

I am not at all heated, but I don't care for having my probity questioned. I think those who feel it neccessary to descend to personal attack and snide accusation instead of answering questions and dealing with issues are not to be taken seriously.

Unfortunately, 'Nimrod' and the sock puppet Rocket has done the cause of Elvaston Castle no good at all.

 

[Jane Smith]

NT wrote: "Solarthermal power for the TD would be a start."

NT, what do you mean by TD?

I doubt that we'll be able to use anything solar on this as the building runs north to south, with no south-facing roof-space. The atrium will have one small end facing south, which will help some: but I don't think it's going to be good for solar gain.

We've seen some information on rammed earth techniques but concrete, along with lots of drains and membranes to keep the water away, seems to be the way forward.

Here are a couple of photos which show the stables, and the dug out bit behind them. You should be able to click on them to see bigger versions.

 

[Nemesis]

Yes, a little like ours - part underground but without the added benefits that proper underground building should bring.

Here's more about the Cumbria house, sometimes inspiration and other leads come from seeing what others have done:

http://www.theundergroundhouse.org.uk/

and another useful site:

http://www.earthhomes.co.uk/

I have no idea if strong hydraulic lime could be used instead of concrete...

 

[NT]

NT wrote: "Solarthermal power for the TD would be a start."

NT, what do you mean by TD?

Tumble dryer, a load best run by low cost warm air collectors. I dont recall if yours is lectric or gas, but if its electric you'd free up a noticeable amount of energy for very little cost.

There are other more interesting ways to dry clothes if you wanted to be adventurous. I'll stick to the sane ideas in this post though

I doubt that we'll be able to use anything solar on this as the building runs north to south, with no south-facing roof-space. The atrium will have one small end facing south, which will help some: but I don't think it's going to be good for solar gain.

How big will this south facing wall be? Even if it were just 12 feet wide and 1 or 2 storeys high, thats stll a useful amount of heat, as long as you use warm air rather than hot water.

12 feet x 16 feet = 17 m^2 = vaguely in the region of 5kW+ in winter. Put lime chippings on the ground in front of it and the figure gets higher.

Dont forget underground building requires less space heat, since underground temps are much higher than outdoors in winter.

Then theres the q of whether that wall could be made bigger, either with a bigger structure or by adding say 4' mini wings to it. If it can, you get 20 feet, almost double the output, and you could cover most or all of your space heating needs, plus with a little extra trickery get hot water and an all day oven from it.


A roof is really the last place to put solar panels. Roof access is difficult, costly and dangerous, high price materials are a must all round to minimise any need for roof access, thus install cost is high on 2 counts, and in reality the need for access at times is an unnecessary cost burden which seriouly affects payback.


NT

 

[Nemesis]

We use wind power to dry washing (when it isn't raining) - the pegs and line were very cheap.

A hanging wood and metal dryer is also cheap to run and surpisingly effective, as long as there is space for it. We used to have one in a barely heated utility space, and washing dried very rapidly, what little heat there was collecting near the ceiling I suppose.

 

[Jane Smith]

NT, some good ideas but you're ignoring the fact that we're in the Peak Park and we won't get planning permission for your ideas. It's going to be hard enough to get planning permission for the below-ground stuff. If we add a four-foot wing to the sides we'll block access to both the courtyard and the planned atrium. Also, that south-facing end wall is only above ground on the top story, as there's a hill in the way of the bottom story.

Our tumble dryer is a standard electric one. Can you post a link to a supplier of solar-heated tumble driers? Can't say I've ever heard of them, but I'm willing to look. How much do they cost? How do they work? How long's the payback? I'm looking forward to finding these things out.

 

[Penners]

Jane

I make the following suggestion based on no knowledge or experience whatsoever (nothing changes, eh?).

However, given your situation and your reliance on "green" sources of energy and water, plus the fact that you have some interesting ideas for the building, I wonder whether you might be able to interest the British Trust for Conservation Volunteers.

Given that the restoration of the building will involve traditional skills such as stonemasonry, carpentry & joinery, use of lime mortars, damp management, roofing (how about a green roof?), etc. it seems to me that the project could be an ideal candidate for the kind "learning holidays" that the BTCV runs.

And thus a possible source of free labour for you.

Others who know more about the organisation may shoot this idea down in flames, but if not, why not talk to the BTCV? The worst that can happen is a refusal.

 

[Jane Smith]

Penners, are you involved with the BTCV in any way? Is this just a way to get an invite?

Apart from that possibility it's a good idea. I'll have a look and see if they'd be interested. God knows, we've got enough work here to keep a whole squad of volunteers busy for the next decade or so. And it's snowing tonight. We have full white-out.