Mr Punter

Could you do it like this and maybe even have it step in a couple of hundred mm?

Who did the design? At first floor level, why are there are four leaves of masonry and two layers of wall insulation? Also, what is the point of using the pumice and twin wall on the same chimney?

What are the outstanding snagging issues? I hope the crazy gap ridge tile has now been replaced?

No it wont matter as they will have render beads for the gap.

10-16mm is normal.

The use of the grinder at about 3 minutes was, err, interesting. Holding the grinder the wrong way round, nearly cutting the power lead and not securing the work-piece.

Yes. The heat will dissipate downwards.

We did a suspended ceiling in hollowcore and almost every core we drilled held about a bucket of water!

You could probably get a wire between the planks but you will struggle to go across them.

Imagine if the volume housebuilders did it the same as @NickB. There would be lots of very happy customers.

I have always been a bit suspicious about the rules on using the really annoying short twist nails in joist hangers. They seem quite insistent on it but with some hangers where there are loads of holes and no excessive loads I am sure that even dry lining screws would work fine. The fat twist nails are really easy to remove, so I think they could and probably do work loose but that is perhaps not included in the must stick to rules.

With 2 different foundation systems and on clay there may still be some differential movement. Perhaps design in some movement joints between the existing and extension. Stick with blockwork. Maybe use cement based weatherboarding?

I have been looking forward to this thread coming alive again. Please post pictures - good, bad or ugly.

Oh well, congratulations on selling it at last!

When they redo the render are they still looking at the Helifix crack stitching? It seems well OTT and if these are soft blocks I don't think they will work well. I think any settlement has already happened. The old render looks fairly well bonded. Maybe just a coat of RendAid and finish with OCR and masonry paint.

I think these are I joists, so a no-no.

In my limited experience the SE does the connection details. The fabricator produces fabrication drawings with more detail and you can get them OKed by the SE. Never seen an architect showing anything other than suggested steel locations.

I know it is just a simple case of measuring and setting the battens to the measurement but I would not want to batten a roof for others to slate, unless they confirmed that it was OK as I went.

Where we are, if you submit the application online it is validated within a couple of days but normally the application received date. Once validated it cannot be undone.

Probably. About in the middle of the concrete is good so if the slab is 100-150mm thick it is fine. Why did you put mesh in the foundations? Not normally needed (but it won't hurt). Good luck with the pour. Much concrete?

You just leave SWMBO to @Nickfromwales (when he has finished helping your mother).

Caveat Emptor springs to mind but that does not help you from where you are now. Persist with WPower. Take photos and send them. Establish that is is dangerous as is and they have no right to run the power lines through your property.

I am struggling to visualise how you access the land? Again, a plan would be useful.

There are a few masonry support system suppliers out there like https://acsstainless.co.uk/product/type-1-fixed-back-to-concrete/ I think they are expensive though!

Dark grey or charcoal grout may look OK.