| Archive for Downsizer For an ethical approach to consumption |
| MarkS |
cheapest, easiest, greenest self build?It's spring again, so once again I am looking at French land prices and thinking......As a general question though - if I wanted to do a green/cheap self build what do people think? I'm thinking that strawbale and/or cob for the walls. But, in both those cases I'd need to have a dry set up. So I thought get a timber frame up first, roof it and then build the walls. But the prices I see for timber frame buildings are £££££. What would be the problem with getting one of those steel frame agricultural barns. put that up first and get a roof on. Then building the walls up on an ad-hoc way when time is available on the basis of it being protected. I guess I'd need to be sure that the roof load was within the parameters for the steel roof - but you could just reduce the bay size? I know you can do load bearing strawbale, but that means that the walls are unprotected during the build. Who's done it and what did you do? |
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| MarkS |
Actually - could some kind faery move this to the construction forum where I ought to have put it in the first place?
ta |
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| Treacodactyl |
Moved, but don't call me a faery or kind. 
How do French land prices compare to the UK now the £ is falling against the Euro? |
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| boisdevie1 |
I suspect that load bearing single storey strawbale would be the cheapest. Although this means that you'd have twice the roof area compared with a two storey house so factor that into the equation. Land prices vary enormously depending on the area. In the Pas de Calais you often pay 50k euros for 1000 m sq. You might be better off thinking of somewhere like the Creuse where you can buy an exisiting ruin with 3 or 4000 m sq for less than 30k euros. Complicated. | ||||||
| Blue Peter |
Re: cheapest, easiest, greenest self build?
Is what yopu're suggesting like the picture at the following link labelled: 'Clow Beck Children's Farm' (which was building something within a barn)? http://www.strawbale-building.co.uk/index.php?page=projects Unfortunately, the link doesn't seem to work, but perhaps the owner of the site (Chug?) would be willing to say something about it? Peter. |
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| vegplot |
Consider build a temporary roof and supporting structure under which you build your strawbale structure. Use a Nebraska style of house, that is the bales take the weight of the permanent roof.
Or you can risk the weather and not build the temporary roof, just protect the top of the bales. Any rain htting the side of the bales won't hurt in the long term unless they get drenched or left soaking. You can allow rain to penetrate an inch or two as this will evaporate relatively easily. If you want to build timber frame you don't need a great deal of timber just enough to support the roof. Once the walls are built as they will take load. In some designs once the walls are built the roof is lowered the few inches onto the walls to compress the bales and adding strength to the walls. The roof can be made light during construction with a temporary cover and then clad with finsihed materials once the walls are in place and the roof lowered onto the bales. |
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| MarkS |
Yes Peter, thats exactly what I was thinking.
The problem with load bearing is that you have no weather protection while you are building - fine if the weather is good - but if you've planned and booked time them you want to do it then not wait for better weather. I was thinking you get the bales delivered into the middle of your covered area and then move out from there. There are several plots with a couple of acres available with buildings in various states of repair on them under £50K in Normandy / Brittany / Mayenne. And towards the auvergne /Limousin things are very cheap. eg http://www.jbfrenchhouses.co.uk/2land/brittany/2to5acres.htm And planning /CU seems much much easier. I was thinking that somewhere with an existing small property to give a dry start, then build on to get what you want. Having looked at properties to renovate I can see that the costs are going to be very significant - Im thinking that newbuild on suitable land would be a better bet. Round us agricultural land in small parcels seems to be £10K/acre upwards - with clawbacks if planning is gained. Land in france still seems to be very cheap by comparison. |
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| dougal |
Understand the advantages, but intrigued as to how that would be actually done. Any more info? |
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| vegplot |
Amazon Nails developed a system which involved a threaded stud at each corner of the structure (or suitable loading point). The stud is attached to the frame work and supports the roof. When ready the studs were rotated using a spanner to lower the roof slowly and gently onto the wall plate. It added complexity to the design but solved a particular problem. I've only ever seen pictures of this during my MSc at CAT but I hope to get more detail in May when we attended a course run by Amazon Nails. |
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| Treacodactyl |
I've often wondered if you could build something in a modular way, i.e. build one or two rooms at a time and then extend as and when you have the time, money and the conditions are right.
What's the sort of time scale on a small strawbuild, from when the first bale is laid to when it's watertight? |
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| vegplot |
The walls and roof can go up very quickly, with enough help in a matter of days, less than a week certainly, depending on the size of the building. However, the labour element is rendering the strawbale walls is high and is thus probably the most expensive operation to undertake. The process, is quite long winded as several layers are applied and each layer needs to set somewhat before the next layer can be applied. It is not advisbale to use the more quickly applied cement based renders with straw, they do not have the flexibility, will crack and let in water which gets trapped and rots the straw. You could of course consider other cladding such as timber which would decreased the time taken to finish the walls but timber has a low thermal mass so you take away some of the benefits of a breathable, environment maintaining lime render. |
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| Treacodactyl |
Perhaps not very environmentally friendly but could you use something like a breathable roof underlay as a long term temp cover while you render? Or if it would only take a week perhaps plastic sheeting? | ||||||
| VSS |
i think the difficulty with using a steel frame is the liklihood of condensation on the frame making the straw damp. we had thought to do the same but advice recieved was generally that a timber frame would be better. | ||||||
| MarkS |
Yes, I did think about condensation - but there is nothing to say that the steel frame has to be embedded in the walls - which is where a problem would arise.
Say the supports were 6" to a foot outside the wall (or more? terrace? shade for windows?) ? Or a few inches inside? or coated in some suitable insulating material? You don't have to use the same frame to carry both the roof and the floor of the upper story. I like timber frames, but I can see that the cost of getting one and the difficulty of erecting is likely to be significantly higher than a steel frame. I do think putting the frame & roof up first, with decent overhang should provide decent protection while build + render goes on. I'd also wondered about using clay/straw render rather than lime/sand - but I know very little about clay rendering. I see no reason why you couldnt build in stages - either erect full size frame in one go or just add when needed. Could you get away with pad foundations for the roof supports? You might need to think about the putting foundations in initally for the whole thing. I'm thinking about a wide V shape or a shallow curve (depending on how difficult it would get to curve the roof), south facing, 1.5 stories with central attrium. |
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| Erikht |
What about an A-frame house? They are quite easy to build, and usually comes out far cheaper than other houses. | ||||||
| vegplot |
I'd question that but it depends on how big you want to build. I don't know of any steel framed straw bales houses.
Clay/straw on the internally, lime/sand externally.
I hope so. It's a recognised method for frame buildings. |
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| vegplot |
Metal should be avoided at all costs in a strawbale build where it's in contact with the straw. If it is going to be used then it should be wrapped in hesian or some such. USAan's use metal mesh to consolidate the wall before rendered, this can promote condensation but the have to do as it's in their building codes. Straw bales houses do not use mesh, it's not necessary and it's not done over here. |
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| Treacodactyl |
Have you looked at French prices? IIRC in one of the house building programmes on the TV they imported the frame or oak from France as it was much cheaper than UK prices.
Could you use clay/straw outside and then coat with limewash to waterproof it? |
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| MarkS |
I'll try and track down some french suppliers and check pricing. The UK suppliers are ££££
I know clay on the outside of a building is unusual in the UK - but it certainly does happen in other countries, sometimes with limewash, sometimes with other coverings. |
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| Erikht |
You can polish it with egg white if the climate is dry enough, but what would be the point? I now that here, straw bales would be out of the question. We don't even use straw roofing, I think it's probably against the building codes or something. | ||||||
| Rob R |
Probably down to the big bad wolf. | ||||||
| Erikht |
Real Weather for Real People. | ||||||
| Rob R |
Those temperate days can be hard, can't they. | ||||||
| Mr BlueSky |
Not arf 
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| Erikht |
Blowing a bit. Raining a lot. Might be cold sometimes. |
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| dpack |
the greenest alternative is local natural materials ,all places have a local tradition ,look at the old buildings
they have a local mats b they have lasted c they fit into the landscape or go for hightech but clevertech low impact slab floor ,timber frame ,good insulation and heat/venting ,self supply of water and heat is good check local building regs before getting site or quotes as what seems sensible to us may not seem so to the local planners |
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| vegplot |
It's possible, look at cob, that's nothing but soil and straw and dung albeit compacted. However, lime will give you better weathering resistance. I wouldn't use clay render on the outside myself unles it was fairly well protected from the elements. |
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| James |
have you considered earthbags? . This is building using sandbags that are filled with soil and cement (20:1), mixed dry. The moisture in soil sets the bags after emplacement, so they're soft when you place them, then rock hard within days. If the soil is mixed with porous material, it becomes very insulating also.
The Environment Agency use this technique to build river bank structures. Very cheap, very simple. Then finish the walls with adobe or papercrete |
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| MarkS |
I've seen mud in bags used, but tbh I don't use concrete/cement and I don't intend to start if I can help it. Lime all the way.
I was thinking rammed earth tyres for general foundations, limecrete/leca for slab stuff. |
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| vegplot |
We're going lime all the way as well. You could substitute lime for cement in your bagsif you choose to go down that route.
French oak is certainly cheaper - there's lots more of it and less demand for what there is. English/Welsh made oak frames is of the best quality but expensive, I have no idea what the French market is like but I suspect it's lively. At least you can use hemp/lime over there without too much restriction. |
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| James |
Limecrete sounds good. Papercrete can be made with lime instead of cement, then formed into blocks: http://www.livinginpaper.com/mixes.htm |
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| Erikht |
What about these ideas? I find them very interesting, especially since the houses are complete entities with water, electricity etc:
http://www.earthship.net/ They use old tyres packed with earth, but you can also use straw bales or concrete. |
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| MarkS |
Indeed interesting, but can be a bit radical for the planners,
I've seen one in progress - cant remember the village name - not far from mortain |
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| vegplot |
Planner don't tend to look to kindly on houses made from waste. Something about not being in the vernacular. Which of course breeze block, pebble dashed, uPVC lego houses are. | ||||||
| Brandon |
I would strongly advise that you talk to someone with first hand experience of ramming tyres for footings before you commit to it, it is a killer. | ||||||
| vegplot |
You'll end like with a torso like Brad Pitt in Troy, not get past the first 10 tyres, or dead. If you do decide to go down the rammed tyres route get reasonably fit first and take your time. As Brandon says it's damned hard work. |
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| Erikht |
Can't you use concrete as well? | ||||||
| vegplot |
It's meant to be green. |