Ground source Installation...

A guest entry from Rob - as me telling you what he has told me about putting the ground source in would be a bit pointless...

3 days before Christmas:

We dug the first trench at the end of the plot wide enough to take a single, in line, slinky format collector pipe. We dug to a depth of one metre in the knowledge that there would be further soil from the rest of the site moved over the ground source to level the plot, leaving the collectors about 1.7 metres below the surface.

Because the plot is quite small we then had to dig a trench that was wide enough for two slinkys next to one another. We also had to take photographs to record where, in relation to the fence, the pipes were laid and their depth.

We laid a third group higher up the plot, deeper this time because there was no earth to be moved to cover them. All the collector pipes should be 1.6-1.8m below the level of the ground. We laid 375m in total, actually slightly more than we need for the type of house we're building, a low energy house. Whilst it's not passive (below 15 kwh metre sq per annum) it should be between 15-20 kwh which means we'll be drawing quite a small amount of heat per square metre from the ground.

The hardest part of the job was getting all four pipe collector ends to 'behave' so we could direct them to the point at which they will pass under the foundations. This meant unravelling them prior to their burial and keeping hold of them in difficult circumstances. The small size of the plot made all of this much more difficult than it might have been.

Whilst digging the final trench and laying the slinky the trench collapsed on me and covered my left side, especially my lower leg. I was quite shaken, as were the other blokes, and we proceeded more cautiously thereafter. There were no after affects.