Mr Punter

As per @Conor, there is no spec when they are in the house.

The lawn looks too high and is acting as a dam which is why the patio is not draining.

The joint filler sets a lot harder than the easi fill. I am not convinced either will look good as a textured coating. Why not just get the wall(s) skimmed smooth with multi finish?

The people doing the 3d renders just need the CAD drawings from the architect and site survey people, together with some good quality photographs. You don't need an architect to do the renders.

There is no issue with plasterboard onto the PIR. You will need longer PB screws. It is pretty much what you get with thermal laminate board. I prefer them separately as it means it is possible to separate them at end of their life. Please don't use Fermacell. Massive ball-ache.

Brick acid and a stiff brush. Gloves and glasses.

You could try Mitre Mate.

The EPC says you only have 100mm loft insulation. Top this up to 300mm and it will pay back very quickly.

Why not get some quotes for the gas combi and rads option and compare to the ASHP?

If it is broken you need to replace it.

Well I very much admire your persistence and wish you good luck.

Would it be possible to get the work done, as failing that they may all find themselves homeless, which will help nobody?

Well done for doing your research. Lots of people get hooked into thinking because they have waited a few months and spent 2 or 3 thousand, they are committed to purchasing. The purchase price is likely to be hundreds of thousands, so just write off the fees and be pleased that you have not bought a liability.

Just use https://www.timberbeamcalculator.co.uk/en-gb/span-table/floor-joists?load=1.5&class=C24

If the flue goes through other properties that you do not have access to it is not maintainable. If you are concerned about CGT on the sale you must have made a profit.

They will not be designed to take much loading. I would restrict it to Christmas decorations. Nobody wants to climb up and crawl around a hot dusty loft to retrieve a book.

It is worth noting that in many circumstances, installing a gallows bracket will not be satisfactory. Factors such as neighbouring chimney removal, wall thickness and height have an impact. Often a Structural Engineer will need to be involved. Corbelled brickwork alone is a no-no.

65mm is too thin for concrete and will break up. A liquid screed would be your best bet. I have used Cemfloor (installed by a contactor supply and fit) and it has a decent finish that does not require laitance removal.

How is that easy? It will need scaffold and will raise the height of the roof and affect fascia / soffit and abutments. Maybe I misunderstood you?

That is what I have. I used a chimney type extractor, took out the motor and connected to the ducting to an inline fan sited in a cupboard on the roof terrace.

You often see a course of thermal blockwork for internal walls and soleplate on that. It stops the soleplate being cold and allows for insulation and screed. Soleplate on slab is old school as it is cold and more prone to rot. Also if shotfired they often use l shaped soleplate anchors so as not to penetrate the DPC under the soleplate.

Beechwood Hall in Cooksbridge is clad using Sweet Chestnut. https://www.facebook.com/photo.php?fbid=871128391694956&set=pb.100063934084990.-2207520000&type=3

Slip ties may be better, with a sleeve on one side where you have a vertical movement joint in a panel. For tying to the frame, the normal timber frame ties will be OK.

If you are looking at a home grown timber, Sweet Chestnut is worth considering.

How about fibre cement planks, like Cedral or Hardie? I prefer the smooth finish. They need little maintenance and the finish is long lasting because the planks don't expand like timber. Also they are fire resistant. If you are thinking of fire treated timber you may need to have them pressure treated with Non Com, not just coated. Very expensive.