Mr Punter

Yes that looks fine. I have been caught out by too big a gap left by the tilers and had to get MagicMan to do their thing.

You don't need the zig zag, just an L-shape. Don't leave too much space at the top!

You need to measure it. The council should have a standard size for a space. Where we are it is 5.5m, so if the whole bay length were 20m it may only be able to accommodate 3 cars and so could be reduced to 16.5m without loss of spaces.

Are you laying these brick bond? The one around the WC looks a challenge. You may need a couple of spare tiles. I would just carefully cut a rectangle so the fixings and the flush pipe remain exposed. Do the horizontal first, with a plunge cut.

I have just looked these up as I have not come across them. No powder caps which is a bonus. It looks like you still need the big boy one for fixing timber to steel beam webs?

If there is room in the attic it may be worth working from there instead of from underneath.

If you have a lot to do the multi shot type are a lot quicker to use than having to reload every time.

The most important cut on these wall hung WCs is the one above the flush pipe, which must be close to the pipe or it will be visible after the loo is mounted. The rest you can just go round with straight cuts or l-shaped as you have done. If you have a loo you could do a template around it and offer it up. And yes, you can turn the tile over and do the last bit from the other side.

It is looking really good! Have you worked out where the windows are going - front- to back in the reveals? I looks tricky with the outside walls leaning a bit. Doing the blockwork off a small scaffold tower is quite a feat. Maybe and extra change of underwear will be needed when it goes higher. Will it bond at the corner after the next course or so?

I have used masonry paint. No undercoat but watered down first coat. You could just use emulsion if you want.

I was interested to see how it worked with the wonky walls. Are you doing polybead insulation or did you insulate as you built?

You should have some drawings for this. If you are new to the business it is a mistake to take on design responsibility. You then just price and build something designed and specified by others.

Yes, if the wall is only 3.7 just one strap in the middle. Did you tie the blockwork into the stone outer wall? Can you post some more pictures of progress?

Be very careful about employing someone to do any demolition work who is not insured and does not appear trained and competent. If it is more than single storey, the risks are multiple and serious.

I have used one of these and it was very impressive. The sliding tray was dead accurate. I had some big tiles to cut and used a Rubi cutter where the machine slides over the tile. The blade had a tenancy to wander off. I am not a pro, but the DeWalt is superb.

The dry ridge systems are ventilated and allow the ridge tiles to be mechanically fixed, which is more secure and simpler than mortar bedding.

A few years ago I part demolished a bungalow and burned all the timber on site. Someone stripped and removed the roof tiles for free even though they were only concrete plain tiles. We were only left with the brick shell which was v. cheap to dispose of. Nowadays the authorities probably would not take kindly to the type of fire we had. Be aware of asbestos and if in doubt, assume it is.

The probes are fairly quick and easy to do, especially if you only need to probe 2.5 metres. I would want to make sure the solid strata was uniform around the foundation extents, with no voids. The probe table you have would have been more reassuring if the soil was more consistent, whereas there is very little capacity for the first 2.0m. I doubt there will be much cost difference between probes and trial pits. I would want at least 4. If the results vary a lot, you may need to install piles.

I am with @Bozza on this. Had they decided to scrap the scheme just as you were finishing the build as they needed to make savings I could understand the ire. During this pandemic, lots of people have lost their livelihoods through no fault of their own. Waiting 20 days for the final part of your VAT refund is not a crime against humanity and democracy.

You can have an access point for rodding at the base of the stack. All the internal stuff will have a water trap to stop sewer smells.

That is very rare. They sound like a very good firm - well done them!

There could be quite a lot of money at stake here and so the OP should seek professional advice rather than rely on the opinions of unqualified forum members. Perhaps he can come back to update the thread when he has been so advised, for the benefit of others who have similar situations.

Yes they will and it is far more risky than scaffold, which was already erected. I can't see them wanting to strip the roof to replace the clipped verge tiles without scaffold, although I doubt they would do it anyway without charging £££ extra.

Do they always have a plastic frame?

The main contractor should have got you to approve the works first before striking the scaffold. To me, the broken tile needs attention and the rest is fine, although they could trim the ridge tile 30mm.