Mr Punter

I have not used SPAR. Velfac and Rationel do timber finish on their outward opening products but not inward tilt turn. Cills are down to you to source although they will give fabricator details. Velfac and IC can supply the product with a timber cill packer for you to fit the aluminium cill to. Get the cills to project at least 25mm beyond the face of the brickwork. I doubt Velfac and IC will work for you as the order is small and delivery is expensive.

I doubt it would have the strength for modern construction types. Cavity wall, wall ties, lintels will not work / be properly tested.

Silicone probably will not last very long and may discolour. Can you do it without?

Bear in mind that Building Control may (and should) ask for step free access from the car to the front door. Part M. Failing that you may end up with a very long ramp.

Even if your rights of access are not set out in the deeds, you will have gained prescriptive rights of access.

Yes I do wonder why there is such a focus on steel and fire protection. I could understand if it is a large complex steel framed building, but a dwelling or a small block of flats? I would be interested to see if there has ever been a case in this country that a small domestic building has collapsed or partly collapsed due to failure of structural steel in a fire. I very much doubt it.

When you are working out coursing you add a layer of mortar for every course. For your 6 course of 73mm bricks with 13mm you have 516mm. For your 2 x 215 block and 40mm block slip to coordinate, the mortar beds on the inner leaf would need to be 15mm which is as wide as you should sensibly go.

No, this will not work. The drip from the roof should be in the centre of the gutter. Often you need to put a timber like 4 x 2 on the outside before fitting the metal trim and membrane, but that didn't happen so you will need to get rid of the plastic fascia and fit a timber one further back. As the others have said, the insulation as it is will be a recipe for condensation and this will be more so if you use this for anything other than storage.

Just do it with 130mm and cut it carefully round the sleeper wall plates. It can rest on them. Foam and a layer of polythene as a vapour barrier. The sticky foil does not work well with the dust from cutting.

A course of Marmox or at least Thermolite blocks under the inner leaf will help a bit.

The difference between Robin Clevett's version and what typically gets done on site is vast. The solution needs to be much simpler to allow widespread adoption. The average site worker is not going to cut insulation with a Festool to a precise compound angle. Just not achievable or affordable.

Unfortunately some trades just do their standard thing and will not deviate from it, no matter what is in the spec. Get a quote for putting it right, send it to him and if he still refuses to do it, get it done elsewhere and deduct the cost from his final account.

What is wrong with what he has done? Is it functionally what you needed? Does it look OK? As it stands, would you spend your own money to put it right, or is it just a bit annoying?

This currently states "- 25mm PIR - continuous outside of frame" twice. Is this an error?

A lot of loft conversions do not have Building Regs as they do not comply. They are sometimes described as a hobby room or storage. You would probably need to undertake some work it you want it to be fully compliant. Lenders will often overlook this. I had no issues obtaining a loan on 8 flats with no planning consent or building regs.

You need a fascia to fix the gutter to and a soffit to cover the gap at the bottom. You probably need to get rid of the white pvc fascia and see what you can fix to. The room will only be good for storage.

Why not use a row of 40mm coursing blocks / slips every 2 courses of blocks and fill the cavity with eps beads? 6 course of bricks outer, 2 course of blocks and 1 brick slip inner. Brickie will make it work.

Am I right to summarise that you wanted a £15k discount, your builder, who did a very good job and is honest and diligent, disagreed, so you have dropped the matter?

What is the make and model of the system? I have not heard of a MVHR that anything to do with water heating. Is there a single unit for the whole house?

Get it emptied and give it a jetwash.

The door will have to open into the room. It can't open onto the landing. You could trim the corner off. Pocket doors are tricky to fit and use. A floor plan may be useful.

Well the LA are relying on a dismissed appeal for a similar scheme, which does not help you. The front elevation looks good, the rear not so much. Did you look at adding a new storey?

The water is at least 750mm deep. Why does the proposed access location make any difference? I hope you are more careful with the foundations!

If there is a big concern regarding the mortar they will offer to rake out and repoint. There is no way they are going to demolish and rebuild. If you go to court, be prepared to spend many £1,000s. The house will not fall down.

The refusal reasons sound weak. You could win on appeal. If you do, you could consider demolish and rebuild, where you would save all the VAT and start with a nice empty plot. Why did you add the chimneys?