JohnMo

If the roof space is at 50 -55deg, it unlikely to have a humidity level of 60% at that temperature? Also if you are cooling the air the humidity level is likely to increase, the air in the pipe is likely to be at or close to 100% humidity.

A sketch may help

Simple stud wall a couple of sheets of plasterboard, taped joints and door, build the wall with 3x2 timber, top and bottom plate verticals at 600mm centres. A few hundred pounds. Take someone to court, year to two years, before your day in court (if your lucky), if you win, you may get costs plus a small nominal fee, if you loose, several thousand to yours and his solicitor. Get it sorted move on with your life. Get house signed off, do what you will with the door/wall. Irospective of the person drawing and detailing having missed something, the checker (you, if you were officially reviewing the documents, you state you reviewed) and council should have captured the missing details. I see three parties at fault, the drafting person, the reviewer and council, so who do you take to court? There was no conditional approval it was full approval and BC admitted they made a mistake.

It's not!

It's all rubbish politics. Job protection.... Anyone can export, with G98 or G99 etc. It's just the point of being paid or otherwise. Nothing changes with the system installed or the amounts exported - just the payment zero or something.

If don't mind spending a little more b&q do a recycled plastic bottle insulation - not itchy

Are you sure the ambient and humidity levels are correct?

Sell your left over PIR then go to B&Q or Wickes and buy the right stuff.

Hi - not sure what you mean by the question?

I also got the same statement as above.

I did full DIY on the solar install, except the battery. The PV is basic install with normal inverters. My second array I did a write up on this thread. All costs are included. The battery system will be a Givenergy "all in one" system with full off grid switching in case of power cut. That isn't that cheap at £8200. Without installer permissions you cannot install and commission fully.

Went past an electric wholesale yesterday they had loads of panels. I'm getting a battery, one week lead time and that's basically delivery time.

YES - but You don't need any plaster, as the plasterboard itself is airtight enough. But doesn't mean you will have an airtight house. Just the plasterboard will be airtight.

I wouldn't put pipes under any wall. Someone will end up putting a nail or screws through a pipe. Plan it correctly there should be no reason to. You may get away with if you everything yourself, but if you are getting others to build it for you, good chance of them messing up.

I'll beat @SteamyTea to it kWh

Max output on my gas boiler is 85 deg, so way under the 100. Not much higher than a valiant ASHP really

They end up on your head. Do it correctly with the correct number of fixings. Cold spots from screws - I'm sure it would risk loosing a watt or 2 on the coldest day, rather than killing someone when your ceiling plasterboard falls down.

Leave you tell my wife

I installed my UFH pipes before the walls went up. But the screed type and tolerance to getting wet may be the issue. We used concrete so no issue.

I would be more worried about, the dishes being rinsed before they go in the dishwasher, then leaving a trail of water between the sink and dishwasher.

Would think the spiral patterns are more required where there are high flow temps and big delta T or/as well as doing very close centre distance between pipes. In well insulated house, low flow temp and a low delta T any pattern will be good.

I would say if you have an immersion either directly or indirect you need G3. The safety cut out on the immersion alone, isn't compliant as you need a minimum of 2 layers of safety. So you will also need the discharge safety devises also. In an indirect immersion situation, it would also be a pressurised system, so boiling temperature the would be above 100 degs and it has antifreeze even higher again.

Not sure where you live, but in Scotland you are not allowed smoke detectors in a kitchen they have to be heat, so that precludes most smart detectors as the are heat and smoke. The guidance actually states Google for example are not allowed because they are combined. Also you have to chuck nearly all smart detectors out after 10 years, because they are programmed to stop working due to the aging if the detection bits. And non replaceable batteries.

The reason they want pressurised systems is to keep air out and corrosion.

That's a lot of energy, bet it looses 4 to 5kWh a day. That's what 1 or 2 people person use a day for hot water. £980 for a 210L slimline UVC with a 3m2 coil, that's what I have just paid. Heat that once a day, run UFH on WC without any mixing. Heating 750L of water to 55 is nonsense, to get, not a huge amount of hot water and then blending down for heating? Why would you. A lot of heat pumps will not run open vented. Until mine sees above 1.2bar, it doesn't start.