The Boy on Top
Just out of interest, how far down do you need to go to benefit from geothermal heating?
Not that I could use it, I think the flat below would object to me digging down through them, but I do find the concept interesting.
There's two ways of doing it. Either you lay pipework threeish feet under the ground over a large amount of space, or you have to drill down to bedrock. Needs to be bedrock as its a good heat conductor, yet stays a consistent temperature. We can't do the first, but the later works as the bedrock is very near the surface. TB
I for one can't wait for you to start this project, because you're incorporating so many things that I'd like in my dream house (geothermal, gray water, etc.). So you'll be my guinea pig. 
Yup, there's some fun stuff to figure out. I am expecting much stress and bother, but the technology is all there and maturing now. I shall keep you posted. TB
I'll be interested to know how the geothermal goes. We nearly did it recently, but decided against (a) because the people we were talking to couldn't really cope contractually with retail, as opposed to commercial builders, in terms of risk distribution, and (b) because the outwash from the drilling would have made a horrendous mess and we couldn't drill somewhere that didn't matter.
We do have a outwash issue, but because we're building over where the borehole will be dug, on a slope, we should be able to contain this without notice once the build is complete. That's the plan anyway... TB
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