JohnMo

They are not even that size. Well confused me when I first started buying timber.

Yep But not BTU's or inches for that matter.

Our foundations were complete in the November, walls up by Christmas, was f...ing freezing. Many a morning we would have to bail out the water accumulation before we started work proper. But ICF walls allowed concrete pours even in sub zero temps. Roof on in January. Then it was 99% dry even without the windows, just still cold. Our main issue was the floor was insulated before the walls went up, had 100mm concrete above the insulation, so if there was a sub zero night ,the house floor remained frozen all day

Isn't an insulated concrete slab better, for anything. At least you have only ground temp (6 degs) below you rather than a ventilation void that can be a cold as the air around the house.

I must be doing something wrong, I have to wait until temps drop to about -5 before I feel warm floors. Until then they aren't cold but certainly aren't warm.

I would all to can in PIR and where needed apply spray foam to fill gaps.

Steel, connected to ground will be a cold surface. Wrap in PIR and tape the joints, this gives vapour barrier. 25mm is normally enough but the more the merrier. Or insulation and wrap and tape a vapour barrier. Condensation will only form from constant contact with air

Don't have to have a charger on the wall, a 13A plug will do it. If you have a heat pump, would cosy maybe cheaper overall?

Sorry, you just clump it all in one sentence, can only respond to what I read. But as I said a well designed ASHP system is suitable for any property. But also not mentioned a piss poor design, can be be very bad in any property new or old.

Sorry this statement alone is just utter nonsense. A heat pump is suitable for any property, when correct designed. Why does it cost a fortune to install a heat pump in a new build? You already have to install low temp heating system to comply with BR. A 35 deg system isn't even going to much of a cost premium. If I can buy a new heat pump for £2100, a large organisation will buy for half that! Scotland banned gas boilers a while ago and whole building industry came to a standstill - not. ASHP, no gas standing charge, a single zone system, without hydraulic seperation, SCoP of 4 plus easily. Cheaper for the house holder, get over it.

My view, is do due diligence on anything you read. Who is writing it, what is their background - where is the money coming from, that allows the research and pays the bills. If you can't easily find these details ask yourself why not! Most likely it's going to filed in the nonsense pile or pile of, most likely sponsored, by some organisation with a view to spin.

We had a similar issue where contractors hit a mains water pipe, they got a fine and cost the repair. Bottom line they are the professional, they are the ones that made a mistake, or had an unavoidable incident, it's their issue to sort out, they are or should be insured for such events, if they aren't that isn't your concern or problem. Don't get involved, anyone comes and starts asking or telling you stuff is your issue, pass the contractors details to them. It's not your issue to question, it's the contractors - getting involved just gets you in the middle of stuff you need not be in the middle off. Tell the contractor to deal with it - it's the issue.

It takes all sorts - all opinions are good, even wrong ones. Deleted the rest of the comment, it's not worth the effort.

And if you have solar, no solar no export payments, unless things have changed in the last 3 months.

It does even with my 300mm pipe centres, its way more powerful when you get down to 100mm centres. Uber simple to get working, set flat WC curve, say at 19 degs, let that run 24/7, to keep floor slightly cooler than rooms, have cooling thermostat to switch to second set point say 16-17 degs flow temp, when room temps hits 23 deg. I will be using the smart grid terminals within the ASHP to demand a reaction of 2 Deg in flow temp. My UFH controller is switchable between cool and heat and so is the ASHP, so use a single repurposed light switch connected to both (used to provide a volt free open/closed signal), one position changes both to cool the other position to heat. Pretty much a no brainer, very cheap to run, when between 10 and 25 outside the CoP is between 7 and 9 in the tick away mode, you still get a CoP over 4 running flat out in boost mode when its 35 outside.