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Interesting. All of my valves I can press down manually (no tools). It's stiff sure but definitely movable by hand.

Is the plunger on top of the valve body free to move? Sometimes they stick and need manual manipulation to free up? If the valve body is new I doubt this is a problem. But not sure if you've just changed the TRV or the TRV + valve.

Given the space restrictions you have I guess the answer is no, but is there somewhere outside the kitchen where you could put your washing machine? Might open up more options in the kitchen.

I keep seeing people say that they prefer dry cold of -20/-30 to humid cold around 0. Don't think I've ever experienced dry cold and given I dislike cold I'm in no hurry to try but it's an interesting thought.

Would you mind sharing more about this? I haven't got this far yet (automation is one of those tasks I want to leave until much nearer the time) but this does sound somewhat along the lines of my thoughts.

Welcome! Reguritating some of the things I've learned by reading BuildHub over the last year or so, search the site for more details: If you build to true PassivHaus standards then you won't need much heating. Sometimes on the internet you see people saying don't need any at all but the consensus here is that you do need something, whether its worth the expense of a big complicated system though is doubtful. So think in terms of keeping things simple and the house at one consistent temperature (no zones). With UFH in a PassiveHaus the floor will never feel warm as it won't be running hot enough. Using UFH to provide mild cooling is possibly a bigger reason to get it than for heating. As far as smart stuff goes, try to think in terms of an add-on layer that all basic functions will continue to work without the smart stuff. You want the main services to work reliably (and have the ability to call out someone to fix them if say you aren't around but family is when something breaks). While many self-builders think of the project as a forever-home/once in a lifetime thing, life does tend to throw up curveballs so always keep in mind that you might have to sell it at some point. So avoid doing things that would put potential purchasers/mortgage companies off.

The release of energy is much the same. But the release of energy is not whats causing climate change. That is CO2, methane and various other gasses that act as an insulator in our atmosphere. Our planet has at times been much warmer than it is today and some of the CO2 from that period ended up being sequestered in the ground. Releasing that today is the problem. The sun blankets the planet it many orders of magnitude more energy than all the power plants on earth so the release of a little more from a buried source is not going to change things. Releasing the buried gasses do.

It's not the heat from the reaction thats the problem for climate change. The sun provides many orders of magnitude more heat. It's the CO2 (and Methane) that is providing a blanket of insulation in the atmosphere that is stopping the heat from the sun escaping. That said, the amount of concrete and steel used in a nuclear reactor means that they are a negative for climate change initially much more so than other power generation methods. They work long term because once they are built emissions are minimal. Edit to add: The steam emitted from power plants (not just nuclear) does have some effect on the local climate surrounding the plants, more fog, clouds, etc. Read an article a few years ago about how motor accidents were much more common on a road near a plant due to the commonly difficult conditions. When the plant shut down the issue went away.

I belive that NuScale has one in the US: https://www.theverge.com/2023/1/23/23567711/nuclear-energy-advanced-small-modular-reactor-design-certified Not that it looks like any sort of game changer

They did before all the Three Mile Island, Chernobyl, Fukushima accidents and the regulartory over reaction that followed. All their recent projects are equally overbudget and expensive. The nuclear industry shot itself in the foot when it chose to focus on adding redundant safety systems on top of fundamentally unsafe designs rather than pivoting to self limiting/safe designs earlier. Happening now but a lot of sunk cost.

Agree with all that Steamy. Nuclear is fine if it can be done relatively quickly at competitive cost. Evidence suggests it can not. The only reason Hinkely Point went ahead is because the government desperately wanted to maintain a minimum viable nuclear industry here to support the nuclear deterent. It never made sense financially even before the cost overruns. On this point though, the AI bubble has prompted a whole load of US tech companies to pile into small nuclear. I wouldn't want taxpayers money put into it but if private companies want to push it forward with their shareholders money (and the shareholders agree), then maybe this can bring the costs down. Volume and a sizable order book creates a lot of cost efficiencies.

This LABC doc says a hole of up to 50mm should be ok in a joist 200mm deep. https://www.labc.co.uk/news/how-get-it-right-notches-holes-solid-timber-joists 40mm should be fine for a short run of shower waste. Don't know if that applies in your situation but seems similar. The joist is also close enough to the wall that I would guess you could block out from the wall and attach the joist to the wall either side of the hole to reinforce it if needed or for piece of mind. But please don't take anything I say about this as gospel. I've gone through a similar thought process before with another bathroom but ended up not doing the work so never got to the stage of verifying compliance. Good luck with your surgery. Health should always come first, this stuff (including the plumber) can wait if you aren't feeling up to it.

Can you draw a diagram?

Good luck. Do you have room to angle the bath in the corner? If you are worried about space in front of the boiler it might be an option if you have the space on the wall with the toilet/shower. Tradeoffs might not be worth it but something else to consider.

I found a random freestanding bath installation doc. Looks like this one has space under it to allow pipes to run along the floor to near the edge. Assuming the edge is near the wall you should be able to go under the floor at that point without too much trouble. Again, hopefully someone with practical experience of this will be along to confirm.