Temp

I think two single runs in 10mm one to the hob and one to the oven area would be normal. The 10mm^2 would be terminated at the oven/hob end with a accessible Cooker(hob) switch and a Cooker Connection Unit (faceplate/junction box thing). Run a 2.5mm ring to sockets as well so you can choose later if you want to hard wire the oven to the 10mm^2 or just plug it into a socket.

Depends on the distances and load but yes the 10mm would be for an electric hob or combined oven and hob. Many Electric ovens (without rings/hobs) only need 2.5mm^2 and quite a few are supplied with a plug to suit standard socket.. 2.5mm is for sockets (ring mains effectively have two 2.5mm^2 in parallel as power flows both ways around the ring). The 1.0mm^2 is for lighting but some people prefer 1.5mm^2 as I think it can be covered with insulation without derating? However with LED lighting I don't think that's the issue it once was.

If I've done my sums right.. 4.5kW = 4500J/S Water needs 4200J to raise 1L by 1C or 100L by 1/100th of a degree. So with no heat being removed/lost I would expect a temperature rise for the whole tank of about 1/100th of a degree per second. Perhaps a bit faster. So a 10C increase would take about 1000 seconds or 15-17 mins. A 50C increase from 10C to 60C would take about 75-85min. If any energy is being taken out at the same time that could extend the warm up time dramatically.

Did the architect specify any straps linking the rafters on one side to the other over the top of the structural ridge? Perhaps not needed as you also have structural purlins as well but perhaps check. Edit: Ah I see @ProDave already raised this.

I think 70cm gap between island worktop and cabinets on right in the "photo" is a bit small?

Are all those numbered 24 the same size so they can go anywhere where that size is needed. Ditto the 25?

Yes....This pdf in polish has similar format numbers at the bottom.. SAINT-GOBAIN GL.JAR 01/03/2019 SGG Climaplus 3190372/15 https://glassolutions.pl/sites/glassolutions.eu/files/2020-12/KARTA%20ODBIORU.pdf Zlecenie and Pozycja in the boxes translate as job and position.

Since it's got dimensions the 3626391/24 could be an order number and pane number. Eg pane 24 and 25 of order 3626391 ?

Google where to drill joists. Should find a drawing showing zones where you can drill from the ends and hole sizes...

Google found this pdf but I don't think it helps any. Not enough info on the lable you have? https://nl.saint-gobain-building-glass.com/sites/saint-gobain-building-glass.com/files/2019-10/CLIMAPLUS_BRO_BENL.pdf

Yes that's correct. The membrane should drape/sag about 25mm between rafters leaving 25mm air gap. Should be ventilated at ridge and eaves. The drape is to stop water pooling above battens causing them to rot.

+1 It essentially just a capacitor. You wire it in parallel across any light fitting. Normally only need one even in a room full of down lights. 10 min job just don't pull all the wires out and forget where they go 🙂

Whatever it is it's crap. Looks like 2nd hand/used shuttering plywood. Should be at least 18mm thick but I prefer 21mm. Check the joists are the right dimensions for the span first.

In most cases it's caused by the capacitance between live and switched live in the drop from light or junction box down to the switch. Power effectively bypass the open switch to get to the light. With old incandescent filaments their resistance is low enough that the switched live is effectively shorted to neutral by the filament. With LED bulbs that's not the case. One solution is to put a resistor across the LED but that would burn power when the switch is ON. A capacitor in the same place still burns a little power but I don't think it's metered as it's reactive power? I might be wrong about that. I suspect there are folks on eBay selling magic capacitors to fix the problem but you can buy a general purpose capacitor more cheaply. If I remember correctly it's a 0.1uf class X2 but can't swear to that.

An electrician should be able to fit a capacitor that makes the light go out. It doesn't actually stop the power being consumed but that's normally tiny.

Could switch to mains pressure and just disconnect the tank leaving it in place. Main consideration would be the condition of the pipes. Good enough for mains pressure?

+1 Hybrid roof has risks because it moves the structural wood towards the cold side. Ideally you would need a condensation risk analysis done. I have heard recommendations that no more than 1/3rd of the total insulation should be below.

The normal rule is no building within 3m of a pipe but that rule that does get broken by build overs and sometimes they allow closer (1.5m for example). You won't really know until you ask about a build over. I think a diversion might be possible but as the pipe is in concrete that's not an easy task. They also tent to want manhole access where there is a change of direction so might need two of those as well.

Quite nicely popped. The ones I've had fail on other kit usually just bulge up a bit.

We got completion in England with.. No kitchen fitted Two bathrooms without 2nd fix (no bath, shower, loo or basin). Lots of missing wall lights (just a chocbox wrapped in tape). One wood burner not installed. This is what I remember our BCO wanted to do on our final inspection: Checked outstanding issues from previous visits had been done. Checked the electrics were signed off. Witnessed our builder pressure testing the drains (required me to cap off some pipes waste pipes with plastic bags and tape). Inspected all glass that needed to be toughened (eg infill panels on stairs, low height windows etc). The BCO said he was looking for the "kite mark". He couldn't find it on some because they were faint. I had to find them for him while he carried on. if there is ever a next time I would find out where the marks are in advance. Tested all coated glass in windows with a resistance tester? That showed we had some panes the wrong way around but it didn't bother the BCO. Checked the height of all window sills and the clear opening width. Failures allowed: He noticed lack of air brick in the room where the wood burner was going. I pointed to a MVHR vent in the ceiling and said we had an air vent system. He thought about it for a moment or too and moved on. He discovered two upstairs window sills were too low by 1-2cm but signed us off on the understanding I would fit window restrictors to prevent people falling out. This was in 2007 so they may want more stuff now? Air tightness tests?

You have at least one blown capacitor on your PCB.

New vs used?

Get a copy of the title plan off the land registry web site. Beware scammers who add a mark up and get it from the same site. Last i looked the real website only charged £5-£10. I suspect your boundary is the red line on the drawing you posted. I think you might be able to divert the pipe along your side of the boundary around the proposed extension. If they wont allow a build over I would work out what separation a diversion would give and get a plan drawn up for their approval.

Don't worry too much. Your plumber is probably just miffed you got someone else to do the pipes. Perhaps apologise with a crate of beer and ask him to fit the isolation valves the other guys forgot. 🙂

Yes just add a vcl below the rafters and before plasterboarding. Perhaps seal any gaps between roof and walls before fitting the VCL.