Nickfromwales

Get rid of the T before the tundish. If you’ve no more height to play with, T the 22mm D2 as low as you can, do a second riser and fit a second tundish. The swirl of water hitting that T as is, will see water going everywhere except into the tundish. A strange phenomenon but ask me how I know lol. Nice work btw. I’ll look again later to see if I can add anything more. Get some Munson rings on, and then you can lose the battens and insulate freely.?

They're too short-handed to sort that in 9 days boyo.....

You have a cold, stone heart. If you didn't have a lump in your throat at the end of that then you must be deader than Scrooge McDuck.

We're in very high demand

They actually use very expensive breathable paint specifically selected for application on ‘wet’ plaster. I asked when I did DIY SOS in Swansea. Not a single corner cut on that one, and I expected to see some being cut of course. I think the unfortunate folk who benefit from such help would not give a toss about some shrinkage cracks, nobody in a Persimmon or Wimpey home do, and theirs take a lot longer to build

Preferable yes, but you need a good spread to get things dragged and floated on the first sets so the end result is flat / plumb etc. For D’N’D I now stipulate a minimum of 70% adhesion, plus a continuous bead around perimeters / sockets etc. All methods can be done badly so it always falls back to the tradesperson undertaking the work, every time.

Less gin, more tonic ??

It’s 40mm minimum if a 32mm waste plus the thickness of the fitting has been lost. So ~60mm of brick plus ~15-20mm of cement render & plaster remains. Not going to fall down any time soon, but probably best to confirm this isn’t taking the hop of the roof or chimney etc before ‘accepting’ this compromise.

I wish you were around to show a few guys I've met exactly how to D'N'D properly mate. Some are still out there working with 12 miserable dabs to a full board

And then you're at the mercy of the shape / state of the walls. No thanks! No blockwork walls go up precise enough to do that, none that I've ever seen anyhow, so all of the kickers in the blockwork and the out-of-plumb bits transfer unhindered to the plaster-boarded face unless you go about spending an age packing and levelling each batten. Even then you only get a vertical batten but you don't get a straight wall as each batten is not flush with the previous / next batten unless you really turn into the batten fitter of the year. Pointless ball-ache. Chase the boxes in 15-20mm, clip the cables to the blockwork, parge the boxes in, and dot n dab to an immaculate flat, straight wall. Plasterer only has to finish then as opposed to dub and finish.

It's all down to quality of work, whichever you chose, and attention to detail. I would parge the blockwork, fill and smooth any chases / back boxes etc, foam and seal joist pockets / other penetrations to atmosphere if you have them, and then dot n dab. You won't get a plasterboard / thermal 'tent' if you mitigate against it. Knowing how / where to successfully mitigate is the key to success.

Yatzee! I automatically assumed vertical chases. That's a chunk missing from that wall. Sorry, I now agree with your concerns. Yup. 100% or popped the floors up. At the very most I would have removed just the render and set the waste pipe as far back as possible to reduce the footprint of the boxing in. Not even sure if backfilling with a stiff cement compo would satisfy here.

We retrospectively cut doorways into load besting walls, so a bit of chasing will be of zero detriment. Electricians will do that 4 times or more in the same wall before breakfast. Zero BCO or structural issues / concerns have ever been raised in the last 25+ years of doing this exact work. Time to put more tonic in with the gin

They’d use piss coloured cement then most prob ??

Just wait until the BCO see's it and condemns the work. Totally crap workmanship.

Just screw them down a-la @PeterW’s advice! Making holes in membranes is neither here nor there. Failing to keep your UFH pipes down on the deck will be a multiples of £1000 fcuk up with no chance of repair. Seriously……. Just drill the 6mm hole for a concrete screw, then immediately prior to putting the screw home fill the hole top with sealant, smother the screw thread, wind it in, and repeat. This will be of zero detriment to any of the layers. Screw them down or prepare to fail.

UFH can be pushed into a convenient corner. UVC needs priority. That’s how I set out for all of my M&E projects, with priorities appropriated.

Thank you. However, you will actually be FAR better off with the single 500 afaic. With PV you will be able to force feed spare energy into that via immersion(s) so you’re basically paying a few hundred quid more for a big, basic, energy capacitor. Don’t fear a 500L uvc, that’s pretty much what I would put money on would best suit your ‘predicament’. With PV it also provides a runaway lane for excess so 2 birds one stone.

Is it far from Truro general? I know where that is. Nearly chopped my leg off on a ship in Falmouth dry dock, when looking the wrong way whilst holding a 9” grinder with the trigger held on…… How we laughed. ?

After 3 pints I may fall for that one. However, the cost of splitting the system is huge and the losses expanded, so the swords remain crossed my pastie-loving opponent.

Not yet a practical answer to the OP’s question. Your reply is a bit ‘wider afield’ and better off in a dedicated thread. The OP mentions a HP ( a well established energy multiplier ) and PV pus diversion ( so harnessing an energy source that promotes responsibility, at least as much is reasonably expected from a domestic residential setting aka Joe Publique ) so best get them apples and apples in a line me old China mug ?. Saving the planet is one thing, but not getting clubbed to death by a blunt instrument because the water ran cold is ‘slightly’ more pressing. 6 bed 6 bath. And a thread titled “Hot water cylinder size?” Back on track please.

Forgetteth’yea the above mention of PV and diversion? Summertime DHW via PV top up for at least 6 months of the year, and then who’s gives a Foxtrot about the CoP in the winter? The OP states they need a practical solution for lumps of DHW, so a sensible approach is not to dip under 55oC as that would push them to a bigger cylinder. Your turn

Yup. I know. What temp do you suggest instead ?

At the very least, they should say “this side up”