Riddler266

We've just got plans passed for a new build on our property. We are demolishing and building where an existing stable is, and building a new wooden stable in the field. We want to install a ground source heat pump, and I have a couple of questions.. 1. In the house I've seen a Bosch unit which is a Combi and contains a tank. It looks about the size of a tall fridge freezer - is this the only internal plant needed? 2. The pipework. The first job for us is to build a new stable and sand paddock in the field - then clear the site to build the house. I thought this would be an idea opportunity to bury the coils under the new sand paddock and possible under the new concrete pad for the stable also? I've read that they recommend 2-3 times the area of all the floors square footage being under floor heated. This only equates to 1/3 of the sand paddock area, so we should be good. So my thought is to acquire the correct type of pipework and have this buried whilst building the new paddock. Then next year when we start the house it should be a case of connecting up to these and we're good to go. Is there anything wrong with that approach? Thanks for any advice. Rob PS - Architect has also recommended onsite sewerage management (ie not connected to mains) does anyone have any tips for this too? PPS - I'm sure I'll have LOADS of questions as we go through this, it's our first experience of eco homes and self build!!