Mr Punter

I sometime pay people by the hour. Make sure you establish whether they get paid for breaks etc. I prefer to just pay for the hours worked. I like a timesheet but it depends who it is. We had some bricklayers where the boss paid them day rates. Start, break and home times were very strict. Our cleaner gets paid a fixed amount supposedly for a set amount of time but sometimes she does longer or shorter. We have had the same arrangement for 30 years.

Maybe it gives the occupant time to lose enough weight to squeeze through the narrower gap.

He is using pedestals

Yes the Compriband. You will get more results than if you search for Illbruck or Tremco.

Someone called shevek at Green Building Forum did an eco retrofit (Enerphit?) and posted much about it. May be a good contact.

If you post up the photo we could take a view. Is the whole building demolished, or just the mezzanine? Even if there are some supports or fixing holes it should help your case.

Years ago I knew a bodgit builder who closed off a chimney breast, skimmed, woodchip papered it and painted it all in the same day.

Make it 33". Fit a door closer with a hold open function.

Spax seem pretty good. https://www.spax.com/uk/projects/outdoor/decking/ If this is to screw the boards down, drill a full diameter hole through the board and a slightly smaller one into the joist the depth of screw embedment.

My, what an attractive verandah you have!

It depends what was specified. I have seen some insulation fixings where the screw is recessed far down into the large head of the fixing so if the insulation compresses the screw does not pop through the membrane. Because you have pedestals and raised paving, you should be able to avoid placing a pedestal base directly on a screw head. You can always drill or cut out a bit of the base if a clash is otherwise unavoidable.

The Compriband has a BBA certificate and a 15 year performance guarantee. I have bought it cheaper from ebay in the past.

But if you have dot and dab air leakage can be anywhere / everywhere because often there are gaps in the blockwork, holes smashed through for services and you have a plasterboard tent. I have often felt cold air coming through sockets etc. on dot dab walls.

Wet plastered onto the blockwork is much nicer than plasterboard on dabs. You will know the blockwork is properly sealed. If you have plasterboard on dabs the blockwork can let in a fair amount of air. Any small holes will can let external air in and it just circulates behind the plasterboard.

Email a copy of the planning consent.

They don't. I guess the chipboard expands / contracts at a similar amount as the joists - not much.

The insulation can either go under the concrete or on top. As it is a ground bearing slab the make up will depend on the ground conditions. Double check with the building inspector as it is best to be on the safe side.

With timber frame the floor deck adds to the strength of the building and the deck is fixed over the entire floor, excluding the stairwell. For internal partitions you can use some isolation strips at the base. Leave the plasterboard 5mm short of the floor. The Screedboard suggested by @Dan F is very good but you lose some ceiling height. You could use resilient bars on the walls. They are fairly cheap but help decouple the plasterboard.

With the designs you have you could bring the cost down and make the houses more comfortable by reducing the glazed areas in some of the rooms. Full height glazing in bedroom windows that are overlooked and / or amount to more than 25% of the floor area are worth altering. Glazing is far less energy efficient and more expensive than external walls and you can end up with unwanted solar gain / overheating. Use it where you have great views though. I notice also that the oriel window on the back could clash with the window below and downpipes and window treatments are almost impossible with a glazed gable. The garage looks a tricky cold bridge.

You will achieve a far higher price per square metre for this sort of thing and it will be cheaper to build: https://www.rightmove.co.uk/properties/80178027#/

I really like the website and some of the houses they have look fantastic, but they often seem less expensive than more mainstream stuff. Some look very expensive to produce but they are a bit niche and quirky for a spec developer. https://www.themodernhouse.com/sales-list/hedge-house/

I have looked at their listings in the past and it struck me that the prices were no higher than more standard types and that the houses seemed to stick for longer. Lots of things are personal preference and the OP could do well to concentrate on items that have universal appeal, like good location, easy to park, attractive front elevation and entrance hall, gas boiler, equal balance of living and bedroom space.

25mm x 50mm battens is fairly standard. Stop them short at the top and bottom of openings to allow air to fully circulate. You will normally go round the outside of the openings with the same.

Concreting is one of the most difficult jobs to get right. Even if you are experienced and well set up it can catch you out. Late delivery, pump gets blocked, wrong mix, wrong weather, not enough skilled labour, poker doesn't work, goes off too quickly / slowly.

Yep. You go girl!