Dave Jones

im a fan of the cast iron spindles as well.

whats the stairbox price ?

yep.

letter prior to action against the Qualified architect designed it. See if any of your insurances have some legals with them.

rads.

just put a cheap fire door in to pass regs then swop it out after.

there's a price limit for every location. if the location doesn't increase the price the size has to come down to make the maths work. 300m2 is very very niche size.

same, don't forget to add dishwasher, sink and a toilet being flushed to get worse case. I'm doing a min of 3 cylinders (will keep adding them until we dont run out of hot water) and a buffer. Making sure the plumber runs separate runs to every bathroom etc.

place is too good for the location.

just a squirt of sodium hypochlorite every couple weeks.

whichever gives you the longest straightest run

its almost as if whoever designed this had it in for you with that terrible insulation design. 100mm of cavity batts would have been 1\4 of the price, be fitted easier and give you a better result. If you paid a 'professional' for this design I'd be instructing solicitors.

a good example of chasing your tail trying to heat only sections of an insulated box. End up spending more money than if it was all just left to balance. If you have a poorly insulated, leaky shell on the otherhand micro managing and force heating sections may be only option. I remember growing up with the only heating being the open fire, rest of house freezing. No way that fire would heat up whole house no matter how much was put on it.

building is very difficult to 'book learn' i would say. Practical is very different from theory! Read up the NHBC techical library which is free, as are all the building regs.

im looking at a 9kw panasonic aquera as running it at 4-6kw is its most efficient apparently.

@Big Jimbo try https://www.changeplan.co.uk/heat_loss_calculator.php It's a lot easier to use, i just entered ours as a box, similar U values to yours and at -15C out 21 in im getting 6.6kw for 211m2

the OP as was asking for build cost prices, wouldnt be fair to exclude massive amounts of labour costs as this paints an inaccurate picture. Our build going well thanks for asking, nowhere near your £875 m2, think the 2nd fix items alone would put it past that!

Be wary taking notice of this, this is not a standard build. It's like buying a car and not including the engine as you made it yourself. Normal costs are an absolute minimum of £2.5k m2 NOT including groundworks.

Construction drawings ? What stage of the build you at ?

fan coils are not aircon and never will get as cold. The lowest temp needs to be above the dew point so the pipework doesn't condensate and rot out the house. May be worth investing in electronically controlled blinds to stop some of the heat getting in the first place.

you need to find the cause of the damp, it could well be you. Buy a cheap humidity reader and take measurements inside for a couple weeks, compare that to outside. How are your kitchen and bathrooms vented ? Do the windows have open trickle vents? Look for any obvious external factors, gutters blocked, overflows, poor masonry etc Has any insulation anywhere been added recently?

what makes you think that ? The whole house should be (and is required to be by SAP) surrounded by a continuous insulated box with minimal cold bridges. Just heating a corner of that box will reduce efficiency and cost you more for no net gain hence zoning in boxes is pointless. Why the massive hassle and expense of block and beam for first floor ? Planning to park cars on it ? You wall construction looks like 300mm, that's going to cost you in expensive insulation and labour time to correctly (they wont)detail it. Have you already got building regs ? Have you got construction drawings ? The more you simplify the whole build the better chance you have of getting it built correctly quicker and not costing you both kidneys.

the reality is a ASHP install is at least treble the cost of a combi, you have the hassle of tanks so you dont run out of hot water and the noise as silent they are not. But if you can build airtight and reasonably well insulated so you can run at a low flow temp then your long term costs are comparable. If you cant run low flow temp it WILL cost you an absolute fortune to run hence the horror stories in the press.

as accurate as your plans. Provide the structural engineer drawings and they will price steelwork as well. They use rates for your area but you can override day rates to suit. They will not cost as they cant, your costs to get out of the ground so groundworks costs.