TonyT

Think it’s time to get the installer back to check the wiring, hopefully it will be an easy fix, then Check all the parameters are correct

Get some tar from roofing merchants and fill with the same material

https://www.tlc-direct.co.uk/Technical/DataSheets/Other/Shark_IPx8.pdf or some of these if the joints are buried

You need cw armour glands say whiska joint boxes for looping in the SWA and terminating the conductors. I do like wago connectors inside, makes for quick termination. Stuffing glands for above joint box to take the light fitting flex. possibly pirrana. Nuts for the swa glands cause the box is plastic and if you aren’t a spark looping frying pans on the CW gland may be a pain.

Building control are hardly interesting in doing foundations and drainage checks, they aren’t going to be the least bit interested in outdoor lights. if you get them in, all they will want to see is a certificate to pass the blame onto, and then charge you for their 20 second tour of your garden.

May be a simple 2 way switch with 3 core at one switch and the other end at the other switch with a 2core as well

You need to look at the existing terminals marked com, L1,L2 and replicate on new switch. Best to take plenty photos prior.

Yes, I did this a few years ago, they can terminate the live pipe where ever you want.

You get extension bits for core cutters or you get 1m long masonry bits and you could chain drill a hole

My plumber only installs viesmann boilers, he’s a fan of them.

I cored a hole for the flue and it took 12 plus hours( borrowed all the correct gear from work) when we first bought the house i kango’d a hole for a waste pipe years later when we did an extension and it it was done in an hour! so coring for me had no making good, kango/img the hole required some making good but was still quicker

Suppose it depends, you could kango a hole insert pipe and rebuild quicker than it could take to core the hole, depends on the stone, but that’s my experience with my 600mm thick whinstone walls.

Good for sanding metal railings, never seen a first fix joiner use anything like it…

Put 3x2s in to catch the fixings, ie a full noggin/dwang

You worry too much

You don’t need full sheets You need to figure out where the fixings are for accessories and put a rectangle of ply in for that item, ie towel rail, a piece bigger than the towel rail fixed to the wall. same with the sink, WC, toilet roll holder etc

Has the immersion kicked in? PV definitely working?

Under the kitchen sink, more room to add stopcock, change from underground pipe to copper/plastic. Easy to get a main bond to it, there is a requirement for water at the sink anyway so makes sense, of course if you had plant room it would be there, even an attached garage I would consider it in there, just to keep access to the stopcock easy.

As a minimum I would use the 50mm twin wall over the other option you proposed I prefer to stick to 100mm twin wall, gives future flexibility for adding extra cables. swa cable and exterior grade data cable will be fine in the same duct.

Air to air for the heating and cooling with a cylinder for hot water with a 3kW immersion, would doubt that a new supply is required for that?

Take lots, send in the ones that show the work in a good manner, I just took photos and did nothing to alter/edit them. just advised that pic 1 was new drainage, pic 2 was air bricks, pic 3 was etc etc. Look at each photo on the PC to see that nothing in the background highlights any issues, things like bottles of fairy liquid next to cement mixers!

What about some local air con installers?

Yeah , we do that sometimes , it’s quicker and you can get full sheets over the opening and either side so less likely to get cracking.

And ask for the control panel to have a an autodialler, so that you get a text when the sh£t is away to hit the fan, when something trips

What spare capacity does the house consumer unit have? do you know the size of the cut out fuse? helpful info for pointing the design one way or another?