ProDave

Correct and with most transformerless inverters they must not be earthed.

Won't help much if the lightening strikes the panels.

Voltage issue. You need a voltage measurement at your consumer unit, as near the incoming supply as possible, to determine if it is a DNO issue or if it is a problem with the internal wiring, Inverter issue seems to be a supplier / warranty issue. Solis seem to be reliable, the "new Sunny Boy" as far as I can tell.

So what exactly is your current issue?

Generation meters about £20 on ebay. Any electrician should be able to change it. Or do we have the stupid situation that for a FIT system it must be done by an MCS company? (with the MCS premium)? A generation meter is just the same as a normal electricity meter, I have never know one fail, I did not have them down as being unreliable. Inverters on the other hand, mine packed up 2 weeks ago, I just bought a second hand Sunny Boy on ebay.

That graph looks wrong. It says when I am heating my DHW at 50 degrees even when it is a balmy 10 degrees outside, so delta T 40 degrees, it is running at a COP of 0.

So counter the objection to the PP with the fact that you have had exclusive uncontested use of the land for 19 years and that was the agreed boundary when you purchased the plot.

I only know one person who swapped oil for biomass. They lost half their double garage to the massive boiler and even more massive thermal store, and then watched as the price of oil fell, while the price of pellets rose.

The first thing I would investigate before choosing biomass is the claim to be "greener" You will still be sending CO2 up your chimney just as your oil boiler emits CO2 from it's flue. Somehow, people claim this particular CO2 is "good" because it comes from trees that have only recently grown, been chopped down, chipped into pelets and shipped half way around the world. Sorry i don't buy that argument. I like a wood burning stove on a small scale burning local scrap wood mostly from windfall, but I am not at all convinced industrial scale wood burning is in any way a green source of fuel. My fear for these systems is one day, someone will wake up to the fact we are not going to get out CO2 emissions low enough while burning wood, and these systems will become the next "bad boy" just like diesel cars have,.

Headroom above a staircase including the "landing" has to be 2 metres. What do you mean by 1.6 M to "top of the arch"? You don't want a child's bedroom that you can only access by passing through your bedroom do you? So you would be looking at a major makeover including moving the stairs.

Start proceedings for adverse possession if you have proof it has been fenced and used exclusively for 19/20 years.

If youy are looking for an Island retreat, Harris is my favourite.

I have said before, an ASHP will not beat the cost of a mains gas combi boiler. If you have mains gas available and are not bothered about CO2 emissions, stick with your combi. In a well insulated modern house an ASHP is a good solution where mains gas is not available and you need to meet modern building regs / SAP for a new build and the ASHP will give you heating bills close to mains gas prices. Re heat time of DHW is the only issue with hot water. That can be managed, though 5 consecutive baths would be a challenge. I am not advocating anyone to rip out a gas combi from an old house and replace it with an ASHP as the results are likely to disappoint. And this is what gives a heat pumps a bad name.

I guess a disappointment was when my first ebay bargain ASHP was found to be dead 11 months after buying it (first time trying to fire it up) It had been sold by a business seller as "new" It turned out it was being sold cheap as end of line as it was a discontinued model and no longer supported. Tough. Then some good fortune when I found that the company I had bought it from was owned by a much larger company that owns a well know builders merchant. An email to the CEO of the parent company resulted in a replacement, current model ASHP being delivered as a replacement. Previous house now, still related to heating, I self installed a new oil boiler. After 2 months it stopped working. So I took the burner out to investigate. I was somewhat surprised when a load of water came out as I withdrew the burner. Cleaning it all up and emptying it, revealed a pin hole in a welded seam, and water was slowly drip drip dripping into the burner chamber and filling it up. the boiler manufacturer not only replaced it, but paid for a plumber to remove the dud one and fit the replacement. Current disappointment is render issues I have, an ongoing discussion with the supplier is in progress......

Also interesting to see how much insulation is in the frame. A lot of early timber frames had none, just an empty 4" timber frame.

My experience has been 4kW of solar PV is dead easy to self use all year round. 8kW will not be so easy, even with a lot of water to heat to store energy. This is the point where I think it makes sense to look at battery storage. You do have permission from your DNO for 8kW PV don't you? My approach is much simpler, I run the UFH direct from the ASHP and use the ASHP to heat the UVC for the DHW. I time the ASHP to do it's DHW heating after 10AM when I can be reasonably sure there will be a good level of PV output by then, so for at least half the year most of the DHW power comes from the PV. Assuming you get an UVC with a high capacity heat pump input coil, I am not sure it will have much extra room for other coils? Regarding G3, if you know the plumber you can actually do a lot yourself. Run all the pipework to the cylinder and just get him to do a couple of hours work to make the connections, test it and sign it off. All the output plumbing to the various taps in the kitchens and bathrooms anyone can do. I even installed the D2 discharge pipe because that needed to be done early in the build, and the p;umber was happy just to see photographs of the hidden bits and connect to it.

It's normal for the tiles to kick up slightly as the end tiles are slightly raised on top of the flashing around the roof windows.

If this is a high water table, not much you can do. If this is water running down the hill, construct a berm around the perimiter of the garden to divert it around your land.

Reverse the stairs so the access to the eaves space is at the top of the stairs?

So you are wanting to build a house over someone elses access / parking space, so someone else will be parking their vehicle under your house? That might be "interesting" for insurance. Where will you park your car?

Check with Joule that their heap pump is inverter driven. If not it will be more noisy, and a little less efficient.

That is my issue. £600 for a box containing a water to air heat exchanger, a fan, and a drip tray to collect any condensation. For that money, you can buy a complete air to air ASHP aka an air conditioning unit.

If you can get something under there to support it before it collapses you might get away with it. But it won't look pretty. You might want to think about rendering the finished wall? Why have you lowered the soil level that much? you seem to have exposed house wall brick that were never designed to be on show, and is that the top of the house wall footings now on show?

It looks to me like those steps were build on very thin foundations direct onto the ground, and at some point someone has lowered the ground level somewhat undermining what little foundations it had to start with. It is staying put by a wing and a prayer and not doing very well judging by the crack. If you want to keep the ground level that low you need to dig some fresh deeper footings and rebuild the whole wall.

Connecting it to a battery on the micro amp range might not work very well.