Mr Punter

If it is above ground, a coat of primer and of bitumen paint will protect it.

The issue I have with the PV is that if I split it between the flats it is extra cost. I can (I think) just have it all to one connection.

With that kind of price difference it is very difficult not to go gas combi.

Thanks. Yes I was aware of this. The land is being purchased by a subsidiary company. I am not sure of how it works - I leave it to the Beanies.

My concerns about gas are the extra hassle and cost of installation, fire safety and environmental but your points are well considered. I would not, in any case, have a system boiler in such a small flat but a combi is very tempting. Hmm...

I can see why you and @SteamyTea like the storage heaters but I may favour panel heaters. With heat pumps, I did consider just split a/c units to do heating and cooling, rather than a full on air to water setup. I have only used an old school electric shower gravity fed and it was woeful. Would a 10kW unit be considered OK by tenants? A 1 bed flat is about £850-£900 a month, so they want it to be reasonable.

I looked at them briefly but concluded that the downside of more expensive normal rate electric plus lack of control over output may be a no-no. I am probably prejudiced having experienced them 30 years ago. Any idea how they perform in a small, well insulated flat? Would that do a decent shower? No problems with the incoming flow rate. I would prefer no annual checks.

Nice. It is quite satisfying when you can do the whole job in a day, especially if it is something you have not done before.

I am building 3 new flats in Brighton. 2 bed ground floor 70m2, 1 bed first floor 40m2 and 1 bed second (top) floor 43m2. I will be letting the finished units so I am looking for low maintenance. I would prefer not to have gas in the building as I understand the drive is to de-carbonise. There will be shower only - no bath - and I would like it to perform well. There is a bit of space outside for heat pump units if needed. The roof has some solar PV. What would be good to specify?

I imagine they are suggesting they will offer H & S advice compliant with CDM 2015, not that they will take on any of the formal roles (Principal Designer or Principal Contractor). Maybe a wodge of pro-forma paperwork for method statements, risk assessments etc as well as basic site safety. If you have never received any formal H & S training on a construction site it may be worth considering. Find out exactly what they propose to do for the fee.

It is not really worth doing just one ceiling as it takes a while to set up and clean out. You can do the whole house in a day if it is prepped. Cover wires if they have been marked up. Make sure all the plaster is good before you start spraying. You can't easily touch in sprayed surfaces. Turn the nozzle round if it blocks. Good luck.

This is the size chart for the IdealCombi single light triple glazed Futura. Probably similar for Velfac and Rationel. You can get some mighty big windows from them.

I assumed a run of infinite length!

Cut a bit of wood 99mm.

If you have not signed up with them yet, why not just normal beam and block? Could save a fair bit.

Ask Thermabeam to provide you with a typical door threshold detail.

If this is new build you can lose the inner leaf under the door and run the eps and screed up to the brick outer leaf. Doing as you are you risk differential movement where you have blockwork v eps

Too late for Party Wall Act as the work is now complete. As other have suggested, contact the Local Authority planning enforcement about the breaches. Appoint a solicitor to act in relation to the trespass and damage. Get an assessment of the cost to do whatever work is required.

With heavy stone materials it is often handling, cutting, finishing, packing, storage and delivery that make up the bulk of the cost. How are they being shipped?

It seems that buildings, walls, drain covers, kerbs, roofs are easy to plot with great accuracy. There should also be spot heights around the site so you can see the levels. The data should relate to the OS data. I think trees are more difficult, especially where there are lots. No defined points. You can get a tree survey done if you need an arb report. Mention your concerns to the surveyor and see what he says.

I still cannot see without the upper floor. Can you take out a tread from the winders at the bottom and add a step at the top? Also, veering off, you seem to be demolishing a lot of what was there and building a very large footprint of over 200m2. Could you demolish and rebuild to gain exactly what you want, saving 20% VAT in the process?

It sounds like an interesting project. I would be very interested to hear about the pros and cons of straw bale construction.

With a modern well insulated house I cannot see the point in weather compensation. I have seen this for big commercial buildings where it has to be x degrees at 8:00AM. If it is brass monkeys it will switch on a bit earlier. With a new house we had the heating failed and we did not even notice for a couple of days.

I think the bifold screens will cost a fortune. I like the design. Be tempted to cull some rooflights. Lots of solar gain and expense.

If you post floor plans someone may suggest a stair configuration that will work.