Bonner

I am not aware of any particular standard, as long as rainwater does not run towards the house or pool on the slabs, 1:80 should be fine

As you have worked out, second one is probably best. Priority is to ensure the adjacent paving falls (slightly) away from the house. Then it is a matter of working with the lay of the land as best you can. Trying to make the top patio fall away from the house may need a lot more excavation and a step/retaining wall

From what you described nobody is going to say it’s fine, so you might as well go straight to a builder. Hopefully one who can come up with a pragmatic solution.

Don’t know, I just use a brush. I suppose it’s a balance between cost and resilience

Dry mix of sand and cement brushed in is the easiest and cheapest way. I usually give the joints a good soaking and let the surface dry off, then brush in and tamp down with a suitable size piece of timber. Fine mist spray to finish.

Very similar to my last house, everything looks like it’s about crumble (one of the reasons I decide to build new). Nevertheless it didn’t fall down or even show any signs of movement in 13 years I lived there. Unless you want to knock it down, all you can do is stabilise the walls as best you can, mainly by filling/pointing the gaps. The door lintel itself looks solid however the wooden/clad beam running from the corner looks like it needs propping while you stabilise the supporting wall underneath.

I got a lot more sense from the field engineer than talking to the planning office! Hopefully they will come up with a pragmatic solution.

Galvanised one from Wickes, has been surprisingly tough for the price. Don’t go overboard, expect it to be destroyed or nicked!

+1 I just taped up the inlet and outlet terminals outside

You will need to install an in-line pre-filter if you want to improve things, try activated carbon media to absorb fume which brings the smell inside.

Is it Nolte?

It might work only if the flow goes in at the top but I would go for a smaller radiator connected at opposite ends, which most likely to work effectively.

Is the paint actually flaking off? If not and it is firmly adhered to the caulk, it is just shrinkage which can’t be avoided. All you can do is put another coat of paint on the areas but expect there may be further (but less) cracks as the caulk flex’s and timber moves.

Make a feature of it? It will be very difficult to blend perfectly even with the same bricks so don’t try to hide it. You could go with something completely different or decorative brick bonding. Simplest way is to set the new (similar) brickwork in reveal, set back the same as the existing door frame.

Another potential route is an indemnity insurance. I guess it is more or less the same thing as a retrospective warranty but might be worth asking the question.