Mr Punter

Why not ditch the gas and get a decent induction hob? Failing that, def a changeover valve as it will always be raining and 5 minutes before you serve up when the gas runs out.

Can you find out who supplied the beams? They will probably have a design dept who can do an as built drawing. As long as the spans are not more that 4.0m and there are no loadbearing walls it is very straightforward.

Having seen the pictures, if this is in a good location could you demolish and rebuild? With careful planning you could build a near-replica.

Often eaves height is more of a target than ridge height.

I would suggest reduction pro rata per m2 but in negotiating allow them, say, 50mm as a tolerance, so they are only penalised for the other 190mm.

You need to look at every option and rule nothing out. Get some more quotes for the dry rot. Bear in mind that costs for this sort of work can spiral as more stuff becomes apparent. Can you sell the building as is? What price? Can you borrow from friends / family? If you do get to do the place up, could you rent out rooms to help pay back the loan? Bear in mind that your house is still probably in better nick than @scottishjohn's and I reckon you are a fair bit younger than him! Good luck!

It is down to the design. All the best practice says warm roof, everything above the rafters. The reality is there is often a height restriction so it is insulation between joists / rafters and a bit underneath, but this detail is only suggested for conversion of existing roofs. 450 should be OK. Don't forget you also need a 1:50 fall which can add a little. Are your floor plans finalised?

With a 220 joist you can have 300 floor zones. Depends on spans and structure. What is the build up for your flat roof? For a proper warm roof you really should place the insulation over the timbers, so 350 looks not doable.

Either will be fine. I think the Siberian larch varies in durability depending on where it is grown. Denser in cold climates.

Again you may find that quality pressure treated planed softwood works out a lot cheaper. If you get a decent wood stain you will not have to put up with it going manky grey.

I think this could easily have been marked on a plan drawing fairly easily plus an arrow on the elevation with the material shown. The architect could have done this in a few minutes without producing more sets of drawings.

Jolly expensive and I doubt the neighbour would chip in half. Posts often are first to fail, timber or concrete. For a quarter of the price you could get pressure treated timber. 15 year rot guarantee. Should last a while. https://www.wickes.co.uk/Wickes-Pressure-Treated-Overlap-Fence-Panel---6-x-6ft/p/145608

The gluing down of boards is a fairly recent thing. Used to be just glued sheets together and nailed down and they did not always have issues. There is no chance of gluing the floor down now, so I would suggest dribbling D4 glue in the joins and fixing down with chipboard floor screws at 200 centres.

I like that they just fitted the stairs anyway.

Yes, have a look at what moling would cost.

They tend to fit a meter smaller than your connection as they are more accurate. If you want a larger meter they may up your standing charge.

Should be covered by NHBC or whoever

At least access is OK. Hope there is a nice dry spell for the contractor.

I am sorry you are having this problem. I think the solution is to strip what you have there and re-do. Make sure the contractor is responsible for the whole job. Done properly with quality products, single ply, built up felt, GRP and liquid applied all do an excellent job. Go for a BBA approved system and a contractor approved by the system manufacturer. Make sure they produce a proper approved design and spec for their proposals and do not accept any "by others" clauses. The rainwater outlet does not look great. Also I am not sure if there is cavity tray and weep holes just above the upstands. Failing that a coat of Storm Guard on the brickwork above.

You have done the right thing! Bear in mind that with solid joists at 300 centres they are tricky to drill. Also beware of strongbacks, steels and trimmers that get in the way of ducting.

That is indeed a nice looking hole you have there Dave. I puts the others to shame.

I am not sure what you are asking or what you want to achieve. Do you want it to look fantastic from where you took the picture as if it is a main elevation or just practical to live in and suit your needs?

The admins made it so you can only edit for an hour, to stop spammers.

Topps Tiles have the Bal grout colour strips so you could take the tiles in to there and match them. They are expensive so you may want to shop around for the actual purchase.

See if you can get someone to take the pallets for free. They fill up a skip in no time. Alternative is a site fire but it is not really the done thing nowadays.