How deep can these radon membranes go. Is there any reason they can't go flat below the insulation layer and just end up with membrane spanning the whole envelope of building. No corners etc. Any spine walls laid on top.
I still don't think penetrations in the main fire stop ceiling would be good. Probably have to fill the gap between board and light with intumescent mastic. What about standard pb double boarded. 15mm if nessecary.
The building in question already has permission to demolish from current approved planning. That's why I can't see how they could require a new survey as you could knock it down currently on existing permission.
Without side tracking the thread. If you already have had a survey confirming no bats how long is it valid for? Could you use it on a fresh application within 6 months/1 year/2 years etc or does it always require a new survey? In which case cheaper to demo roof pre application
How thick are these led lights? You could just fire plasterboard the whole ceiling, filling joints if needed for fire regs, then fit your lights and standard plasterboard underneath. Maybe some battens sandwiched between if you need the depth for the lights. Make sure joist and truss manufacturers allow for the extra dead load on ceilings.
How much is your gas connection? Where i am the quote is normally in the hundreds not thousands. Like @Mr Punter I'd be wary of solar and heat pump on a spec build. Your house won't fetch any more money for having pv. They can always retrofit this themselves if the calcs work for them. Or do you need it for SAP pass?
Same story with the hear pump. You won't realise any more money for fitting one so just weigh up what is more expensive to install. Like @Mr Punter says you may in fact have some customers put off by an ASHP. It doesn't sound like they have a good rep round your way and the average punter is not going to be interested in visiting buildhub to find our how good they can be if they already have a negative perception of them.
Why is this any different to a normal gable. Some straps off the timber at the top of the wall built into the inner leaf. Job done. Why complicate it? What am I missing? Some wall start ties tek screwed into that steel post if advised by se.
Ok I was only counting above dpc. Not sure on the rates down there. So you've got more like 9k bricks so around 7 grand plus 550m2 blockwork so around 11 grand. 18 grand plus a bit for extras lintels etc.
At this point your best efforts are spent finding some trades people. Pop in merchants get prices for your gear, mention your looking for some brickies. Just get the word out.
What estimator did you use. 3 weeks sounds a bit quick to me but I've not seen or can't remember the plans or elevations.
Whats your quantities or brick and block. If you were to allow maybe 75 pence a brick and 2 quid a block down your way does that get you somewhere in the ballpark? Very rough and im not sure of rates your way.
With regards to getting some decent quotes try to get an introduction or reccomendation off other trades or previous customers. That way your not a cold calling random you're ringing them up saying I know X who's extension you built or I know X plumber who has worked with you guys says you do a decent job etc
I think their planning is a lot more zoned than over here. I assume providing you build within certain parameters planning is automatically given. No silly planners going on about vernacular on a modern estate.
You look at the quality of design of houses here before planning was brought in (1940s?) vs after. Which houses look better?