ProDave

It must do to some extent. I have just gone and measured and the unlit stove is showing as 1.5 degrees colder than the kitchen cabinet it is sat next to, so it must be drawing a small amount of heat out of the room. But it seems to make no practical measurable difference, that room heats up and retains it's heat as well as other rooms.

Your 2 choices are feed the pipes through the web of the joists, but on anything other than a very small room that is going to be a very tedious process feeding a long length of pipe through every web. Or lay battens on top of every joist and you can of course notch or leave gaps in the battens, but that will raise your floor height by 25mm or so so you have to design everything else, e.g. door openings and ceiling heights to allow for that extra build up.

I know you say you have solved the problem, but just saying I am happy with the quality of my XL joinery doors. But i made my own linings (Oak)

DIVERSITY is the thing you are missing. Not all loads are on at the same time and not all draw their rated power all the time. 32A for the ASHP, well if the actual heat pump drew 32A or 7.3kW then it's a 22kW heat pump. Is it really? EV will be charged at night perhaps, when you are not heating or cooking, or perhaps at home in the day, not when you are cooking. Induction hov wil only run at max when you turn all the pans on at the same time. When just simmering the power is much lower. Immersions in the UVC are generally for backup, you would not run both together and not while the ASHP is running. All other loads are insignificant. Nothing to worry about.

Isn't the economic calculation you should be doing to work out if a sun amp is viable, is compare the running cost of a resistance heated sun amp, with a resistance heated unvented hot water tank. Work out how much cheaper the sun amp is (due to lower heat losses) and work out the payback time of the extra cost of sun amp vs UVC

Hi and welcome. I wonder where abouts you are, might not be all that far from me. Yes I have been enjoying the mild January and the lower than normal heating requirements. A bit blowy and miserable today and tomorrow though.

Try GNR Sutherland at Edderton for static caravans (and touring vans but I doubt they have cheap ones like you want) , I am not sure if there is a dealer further north. Easy to call in and have a look next time you are going up or down. Don't get a JCB, get a tracked digger minimum 3 ton, much less likely to get bogged down.

Am I the only one wondering why there is no mortar between the blocks?

Don't do anything until you fit the gates. Only then will you know for sure where the cables actually need to go to and be able to work out the best solution.

This house and previous house have tiled floors on suspended floors with no issues and no cracks.

I think it's 7M in England and Wales, and 5M in Scotland. Mine is only 5M from the house and BC had no issues.

Solar PV is definitely worthwhile and divert any excess to the imersion heater.

Pretty much like us. The ASHP does most of the heating and keeps the house at 20 degrees, but it is nice when it is grey and wet outside to indulge and get the living rooms up to 24 degrees at no cost with the WBS, something we would not want to pay to do by just turning up the thermostats. And of course it then takes a while to cool down before the thermostats click on again and the ASHP comes on so it saves electricity. But it is worth striving to get close to passive house standards, particularly the air tightness and an MVHR ventilation system. That is a revalation to live in.

I don't know that version but I have the Conder ASP6. When I was looking for prices i found buying it from Travis Perkins worked out the cheapest as it was free delivery and offloaded by the hiab on their own delivery wagon.

Let us know how that goes. Okay if there are air vents from outside into the loft. If not you might find it draws air from the rooms into the loft to provide the supply air?

I would be inclined to continue digging out the rubble and pumping out, and at some point you will find where the water is entering. Then you may have a better idea where the water is getting in which might make solving it easier. I hope you have somewhere to put a lot of rubble.

I have a suspicion that it is not the "screws have shrunk" rather the whole lot, except where the screws are holding it down, has risen. This suggests that there is moisture under the GRP whether that is directly condensation on the underside of the GRP or the plywood layer underneath is soaked, but whichever, that wet layer when it freezes expands, except the bit where the screws hold it down it can't expand so the dips form. I don't know what that contributes to finding and solving the cause, but knowing it is probably wet under there might help.

I would forget the back boiler in the WBS that adds so many complications as it's an "uncontrolled" heat source so there must always be somewhere for the heat to go preferably by convection so not relying on a pump. I would still fit a WBS (I have) with a few caveats: Only fit a room sealed stove, that draws it's combustion air from the outside directly via a duct and make sure it is one that draws primary AND secondary air from the duct (not all do) And site the stove in a place that heat can circulate to a lot of the house by convection. We achieved that by double doors from the kitchen / diner with the stove to the central stair well where heat can circulate upstairs and to the living room across the hall also with double doors. Our house has a worse case heat loss of 2.5kW so our 5kW stove will comfortable heat the whole house, in fact if you burn it too long it will overheat the whole house. It is important that the heat can circulate to most of the house otherwise it would very quickly overheat just the room that it is in.

That's the plan. we did that in our last house, set the tiled hearth exactly level with the wooden floor of the rest of the room so you could walk on the hearth without noticing it, yet it performed it's function. I seem to recall BC mumbling something about there should be a step but never made an issue of it.

It was obviously not fully closed then.....

I have just measured ours, and it is 900mm to the underside of the worktop so more like 940 to the surface. Even at that height the kickboard under the dishwasher needed a notch cut out of it. I chose that height so the kickboard would go under without cutting it. any lower and the kickboard would have to be trimmed which must have been the case here. You don't want main units and island at different heights, That will just look silly. So the issue was you did not explicitly say to the architect what height to set the units, the architect made a decision to what he decided was "normal" and the fitters followed his instructions. You will say it was the architects fault, the architect will say it was your fault for not instructing him. Go and search all your drawings and documentation, if you can find anywhere that states the worktop height you might have a case.

I don't see loop length has any bearing on flow rate. Flow rate is determined by the heat output you need. e.g it does not matter of a room has 1 loop of 100 metres or 2 loops of 50 metres, each loop will still need the same flow rate to achieve the same heat output

More of an issue is it might be too low for a washing machine or dishwasher to fit under?

I have edited my post above to show some links to the underground storage tanks. The other half of that setup is the above ground storage tanks by the shore. https://www.28dayslater.co.uk/threads/seabank-tank-farm-invergordon-02-08-09.42247/

There is an interesting "facility" up here, old oil storage tanks hewn from solid rock in the hillside. Presumably they are vented to the surface, but i wonder if the vents were capped how well they would do as pressure vessels. https://en.wikipedia.org/wiki/Inchindown_oil_tanks https://www.atlasobscura.com/places/inchindown-oil-tanks