JohnMo

But doesn't most 'new steel' have a very large percentage of recycled materials in it already?

There is a test on the various mounting methods, (found it in the internet by a UK institution) which look at performance of the PV modules over the year in the UK. The difference was so small it was pretty much meaningless. As said only a very small window where the performance gets downgraded. If we lived in Spain it would be different. The further north you are, then even less of an issue.

He could be running low temp rads, high efficiency modulating boiler or ASHP?

You need to use a geotex fabric, so water can flow through and it keeps soil away from the wood. Something like this https://www.toolstation.com/heavy-duty-landscape-fabric/p62380?store=LJ&utm_source=googleshopping&utm_medium=feed&utm_campaign=googleshoppingfeed&mkwid=_dm&pcrid=560261087208&pkw=&pmt=&gclid=CjwKCAjwloCSBhAeEiwA3hVo_adwDwbVNE8xNkoiWkx6ky62xEYICLbShGHgpgoIgWhBrU8P9DNjDxoCI8oQAvD_BwE&gclsrc=aw.ds

As Dave say it's pretty much down to personal choice. Almost any floor type will work with UFH. We have ceramic tile in kitchen diner, because they suit the room. Most of the rest of the living space is grey oiled oak, all wet rooms are ceramic tiles all bedrooms are carpet. All our floors came in the same approx price bracket per M2.

I would look to buy everything before completion, then you can claim Vat back. Get Electrician to run DC cables, DC isolation switch, DC cables to inverter. AC cable to PV meter, AC isolation switch and then into consumer box. All you need do then is install panels, install inverter and connect up.

Not sure in England but is Scotland septic tanks are outlawed, you have to use a treatment tank. You simplest cheapest may be a pumped solution to the main. Not sure you would have any maintenance, a decent quality pump should last for years. You just need to watch what fats you chuck down the drain, and other stuff that should not go in a drain, like female monthly products, face wipes baby wipes etc, as these clog the pump.

Same as fuel prices went up 5p in the morning and reduced due to vat in the afternoon. Look somewhere like insulation hub, I got great service, delivery by local builders merchant for half the builders merchant price to me.

We are using a Lowara Ecocirc pro. Has an integrated timer, so just needs power. Runs near silent.

Pipe dream. Need huge array to cover winter and shoulder months, possibly producing a 10th of the nameplate production in winter. Could do it in summer with enough panels and batteries. Would need a generator or grid connection also.

Think it's a combination of distance and partly elevation, but mostly distance. Ours big a really deep hole because the hill is really steep at the only place we could site the soakaway.

3 bed. The stupidity of the SEPA rules. They have a limit high/low for the water to soakaway during the test. Above or below that limit is classed as fail. So if you are on bedrock or sand you end up with a huge over sized soakaway. Good thing is it should never clog up. Doesn't look quite so bad with the piping and the lower stone bed.

Were next to a Loch of special scientific interest, had to go though lots of hoops even to get planning. Our treatment plant is near house we then have to pump the outfall 100m to the soakaway to an area, outside the area of influence of the loch. Our percolation test also fails the normal test, as we are on an old sand dune. So I think we have the biggest hole for a soakaway ever. This is it part way through digging out.

I hired from Gap in Elgin, but I think you buy them from HIS (Inverness) as well. But most hire place have them in different sizes

But it certainty helps to know for yourself what each element (floor, roof, walls etc) of houses' U value is and worst day heat loss, even if it's to verify what size boiler/ heat pump you need. Or do a sense check on heating quotes etc. Takes about 20 mins to fill in.

Possibly someone trying to use like a gas boiler? Lots of on off cycles, not sized correctly?

Have you thought about LPG also, you get a modulating boiler that way. You can get it to do low flow temperature for CH. I would consider a hybrid system, ASHP and boiler. Combi boiler (oil or LPG) provides DHW and suppliments ASHP in really cold weather. ASHP does the rest. You should be able to this for a similar price. Or just ASHP and get a few grand from the government. You really need to future proof the system what ever you do. Specify oversized radiators so they work at low temperature flows, get the right sized piping also for the distribution system.

I'm using a Harlequin Hydroclear 6, been running for about 6 months no issue. No moving parts except compressor. As mentioned, in the plastic box they are make more noise than they could. You can hear ours from about 6m away after you can't, will be planting around the compressor box to dampen down the noise further. You shouldn't put baby wipes etc in any toilet! They are plastic and don't decompose. All treatment plants rely on bugs to breakdown the waste in the treatment plant. Bleach (chlorine) kills them. You can use it sparingly, we do one toilet at a time and leave in the toilet for as long as possible before flushing.

Our heating come once per day for a few hours, heating been off for the last few days, our tiled floor doesn't feel cold under foot, it is cool, but not so as you would notice or is uncomfortable. 1 if your house is hot, having a cool floor will be nice in my opinion. 2. Tried a few things but once up to temp heating goes off, but floors stay warmer than cool 3 choose a floor finish you like for t room, everything else is over thinking it.

UVC is for DHW only. I know a combi can deliver different temperatures to CH and DHW. Would have thought there would be system boilers that can tell the difference and do the same?

You say you have the thermostats set for a long burn, what are they set at? Hot water is pretty simple system. Open tap, flow switch detects flow, pump starts, pump water through heat exchanger. Cold water gets heated goes to taps via TMV. When you open tap, does pump start? If so flow switch works. What are the water temperatures from thermal store, going into and out of heat exchanger, when pump running. Are they in line with your drawing? What the DHW temps in and out of the heat exchanger. Are they in line with your drawing? Finally TMV, temp into and out of, based on your drawing do the temps match?

All pretty normal. Add some more screws in-between, sand and fill, paint.

With the floor installation you have, I would go UFH in screed. Small system boiler, not sure if you get them but one where you can run the heating circuit at a lower temp than the DHW. Unvented cylinder. Your UFH will come on once per day for a few hours and shut off until the next day, irrespective of what you want it to via thermostats. Run the whole ground floor as a single zone from a single timer thermostat. No need for anything fancy, as they will not work as required in a high performance house. I took my thermostat out except one in the living space and one in each bedroom, as we are in a bungalow. Put electric towel rails in bathrooms. Ask yourself do I need heating in the bedrooms as the heat will move upwards and they will be heated anyway. I went slightly different route. Combi with thermal store upstream, to collect PV immersion heat; to offset gas costs in the summer, the boiler takes the preheated water up to 55 degs (via mixing valve) it adds heat if it needs to only. Will also be adding solar thermal in a couple of months also, to help displace heating costs in the shoulder months. Boiler works with no short cycling as the UFH manifold (temp set at 30) is fed from the thermal store. Boiler heating circuit is used to heat thermal store to 34 deg (no real losses from the cylinder) with a 4 deg hysteresis. Boiler heating flow set to 40. When running the boiler runs for about 15 to 20 mins and slowly creeps up to a max allowable temp of 55. Then spends about 10 to 15 mins resting. (Still making changes to setting to get it to run most efficiently).

You never know, they may also look at council tax records and completion sign off. Anything to trip you up.

Your test worked