JohnMo

My understanding is. You need around 10-15l for each kW your boiler can generate. So if you have a system volume of over 75l you will be ok without a buffer. The issue come if the have lots of zone or just a couple, where one zone may be calling for heat and it's volume is small. One thing you can include in a buffer is an immersion, so if things go wrong you have a fallback heating system.

1. yes you would have thought of so, but that depends on the flow rate through the coil. If it's flowing too fast the hot water will not have enough time to transfer through the coil. 2. If it's scaled up like the photo of union, be lucky if you get flow through let alone heat exchange. your issue may stem from where the scaling came from, if that is not addressed whatever you change could/ likely to end up the same. your system did work well - then over time performance decreased. From what you have said, may of been down to not enough inhibitor. So nothing wrong with the system design, just a plumber that's rubbish at maths

We are the same, wood, carpet in bedrooms, tiles elsewhere. Choose what suits YOU, not your architect.

I think the main things that screw up heat pumps are the following. Tying operate like a gas boiler, high temp, lots of on off cycles, you need to setup to run at as lower temperature as practical and let it run for as long as possible. One day time temp and a small setback at night of only a couple degrees only (even that is pretty much a waste of time in a well insulated house). Lots of zones, so the heat pump can end up running a small circuit which will end up with lots of short cycling. Have the whole living space as a single zone. I now also run the shower room, utility and en-suites without thermostats, if anything else calls for heat they get heated by default, this is to increase the circulation volume. Heatgeek.com, has plenty of tips of how to balance the system and set up flow temps. Sizing the heat pump too big, always remember, the design heat load is cover a few hours per year, when it's 8 degrees outside the heating system is only doing about half the work as at -3 deg C. If in doubt include a buffer to help prevent short cycling. The other thing about well insulated houses they react quite differently to older houses; our heating is by UFH (we have 300mm pipe spacing - 200mm would have made our system quicker acting), pumped at 30 degrees in concrete 100mm screed, the heating comes on for a few hours and is then off until the next day, with a stable temperature. You really need a simple system, no complex (or expensive) controls.

All the ASHP manufacturers offer hybrid solutions, so may be easier copying their solutions for pipes and valves, instead of reinventing the wheel. It could even be a benifit to use a hybrid controller to get the best performance out the system. Not sure why they would both need to run to stop them freezing up. I assume the ASHP will have antifreeze in it, so it would not freeze, as you have both the ASHP and boiler in the same system (sharing the same antifreeze mix) the boiler would not freeze up either. Also if you are running weather compensation, the heating runs 24/7, but could be setback a couple of degrees only at night. So even less chance of freeze.

No reason why 50mm wouldn't be acceptable. Which ever brand you use they are doing the same thing to mitigate noise. I think 25mm is the minimum acceptable thickness. https://www.ursa-uk.co.uk/applications/acoustic-insulation-floors-and-walls

Just been looking at our photos and there was a week between the final measurements and them being on site to install.

dMEV fan, almost silent, could be used move air from one place to another

Outsourced energy, is where got my UFH parts, worth a look

I got the fabrication company to install our framing. Anything he finds at fault during installation, he can fix at his cost. Got him to also confirm the drawings were inline with the dimensions on site before final welding. All in all no issues.

Here is one report, not sure if it's the one I was looking at. 08_In-roof_Performance_of_PV (1).pdf

Looks just the same as a car air filter and the filters in my MVHR. Pleating makes the filter area larger for a given foot print, not sure what's new in the article? Having a larger surface area allows a finer filter to be installed with a similar pressure drop to a lower performance flat filter.

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.