Week 5 - 30th August - Timber Frame Goes up.

Over the next two weeks the timber frame is emerging out of the ground at a mighty pace. It's so quick to go up the panels (External walls) are just nailed to the sole plates. They are all pre-insulated and have the windows in already, it's almost like a giant lego jigsaw (Sounds easy but I would not want to try it myself) The guys doing it have constructed plenty before so make it look easy and seem to know exactly which bits go where.

The scaffolders have arrived and have put the first level of scaffolding in but the weather has moved in and the site is churning up, the forklift is skidding all over the place and we are sinking up to the top of our wellies in certain areas!! All credit to Lee and Ben they don't seem to stop unless the heavens really open.
The site at the front is getting quite cramped with deliveries from Potton being unloaded and Sand being delivered and moved by dumper round the back for Trell who have now moved onto digging in the 750m of pipe work into the ground for our ground source heating system.
Ground Source Heat Pump (GSHP)
We have decided to invest in some green technology for the heating system. Long term (circa 10years) it will payback, unfortunately we did not manage to arrange it in time to qualify for the £1200 grant but this is (hopfully) being replaced the RHI (Renewable Heat Incentive) which will pay an annual amount for "green" systems. This along with the fact that oil is only going to get more expensive made us decide to go for this heating system. We investigated quite a few options but Nu-heat proved the best system for us as they provide both the GSHP and underfloor heating and were the cheapest supplier we found. Hopefully this will make it easier as one contractor will be responsible for both elements and we will not be caught in the middle.

We have to bury 3 lengths of 250m of pipe in the ground 1m apart at a depth of 1.5m where the ground temperature is fairly constant all year round at  about 10 degrees.  The pipes all feed back to a manifold and then two pipes go back to the house one for heated liquid from the land back to the heat pump and one back out. The principle is that the land is a constant temperature at 1 - 1.5m below the surface so as the liquid flows round the loops it heats up then is returned to the heat pump and a heat exchanger heats up the domestic hot water and underfloor heating.
Sand is used to protect the piping from stones and flint in the soil, you need 6 inches below and above the pipe which does not sound much but soon adds up. For this reason we decided to dig trenches rather than did out the whole area to lay the pipes, there are three methods to bury the pipes. 1) Use a special machine that cuts a slice in the soil and pushes the pipe in to 1m depth. 2) Dig out half the area and lay in sand lay the pipe and fill in then do the next area. 3) Dig trenches one by one, lay the sand and pipe in and fill. We opted for the third method as we wanted to go down 1.5m (to make sure of the temperature) and the amount of sand required for method two was 750 tonnes!!!