The reason for today's title is I've just come back from visiting a straw house that is currently under construction in Orkney. I've seen such structures on TV but never one "for real". It was quite amazing.
Straw bales are used for external walls, packed very closely together, with all gaps filled in (that bit is most important). These are then covered on the outside with 3 layers of lime mortar. Inside the walls are also plastered with lime mortar although clay and other materials can be used internally. This particular house has quite a substantial roof so also has wooden beams to support the interior and the upper floor space. Various technical aspects of the build mean that the house is waterproof - protected from rising damp, seepage as well as rain etc. This particular house had fairly conventional interior damp proofing, but it is also possible to use car tyres as the foundation packed full of gravel - excellent drainage. Again because of this design and it's need to withstand high winds, more internal wood framing has been used than perhaps more protected properties. It should withstand Force 11 gales - and also has "bunding", plus natural landscaping of willow and other trees, and is partly dug into the landscape. All of which will deflect the fiercest of wind.
I know quite a number of local folk have been working as volunteers on the project to learn the necessary skills. Currently in the UK, Building Regulations for houses have incorporated requirements for lower carbon footprint, requiring higher insulation, renewable energies etc.
This current project will use a ground source heat pump for background heating, plus wood burning stoves, as well as having excellent insulation from the straw walls. A local contractor has been involved in various parts of the construction. So it's great that new technologies are being used locally, and with enthusiasm.
Small domestic wind turbines are also able to be used with schemes where any excess electricity produced goes into the local "grid system" and the power company will pay YOU for that, which offsets the amount of electricity you may use yourself at other times.
My main concern would be rodent problems! I live in a solid stone house yet mice seem to find the smallest crack to get in, and while the house was being renovated it was open to all comers! It seems that if the straw bales are stacked correctly and the lime mortar put on correctly there are no holes for the little beasties to get through. I think I remain to be convinced of that having had a ten year battle with rodents in this house! Catching the little beasties IN the house wouldn't be a problem - it's the thought of them chomping through the walls and wires that is a bit fearsome - and as I say I have these problems in a conventional stone house. Though the theory in a straw bale house is there ARE no cavities so they can't move around........
All really interesting stuff. I'm hoping to go back and visit when the house is nearer completion!
I didn't get any pictures of the one I visited today, but here is a link from Amazonails which shows you some designs for straw bale houses: http://www.strawbalefutures.org.uk/projects.html