JohnMo

Sounds big pipe. I am doing about 16m each way to the 3 port valve and have used 28mm Hep2O, have it all in 25mm thick armaflex closed cell insulation, the underground parts is within 110mm flexible duct with the ends seals with stainless steel mesh and spray foam.

What heating system and hot water cylinder do you currently have? What flow temp do you have going through the radiators? What is your house heat loss (or build date and insulation levels and size)?

32mm - how big is your heat pump? Is this under or a overground, inside or out?

We weren't allowed timber battens and had to replace with metal U channel, in that area also. I would add 50mm steel battens (U channel) and then use 50mm Rockwool Flexi or similar, attach the plasterboard to U channel, do the same across the whole two walls - you can see them on the left hand wall.

It not that difficult, I did the same. For those not aware, some info from the HSE website. "Principal contractor - A contractor appointed by the client to manage the construction phase on projects with more than one contractor. The principal contractor's main duty is to plan, manage, monitor and coordinate health and safety during this phase, when all construction work takes place" It also says "domestic clients have construction work carried out for them but not in connection with any business – usually work done on their own home or the home of a family member. CDM 2015 does not require domestic clients to carry out client duties as these normally pass to other dutyholders." You are simply passing the duty of the Principal Contractor to yourself. The bit the contractor tries not to do. "Their main duty is to plan, manage and monitor the work under their control in a way that ensures the health and safety of anyone it might affect (including members of the public). Contractors work under the control of the principal contractor" Basically the Contractor is responsible for everything are engaged to do. But while on site report to the Principal Contractor.

Do your stone slips after, not before. We installed the window to the outside of the ICF, then overlapped the stone slips on to the window frame. Cut the slips to form a neat frame to the window.

So the way it works is DHW is priority, it is heated via thermostat or temperature probe and an adjustable hysterisis and or timer within the ashp controller. We have a 6kW heat pump and a 210L cylinder, our reheat time is between 45 and 60 mins, and we heat in timed slots 7am to 8.30am and 2pm to 3pm. It almost always heats at 7am, sometimes at 2pm. All other time is for house heating. Switching between the two services is via a 3 port valve. The ASHP automatically adjusts flow temps.

https://www.pandhengineering.co.uk/advice/assessing-underfloor-heating-systems

All I am doing is altering the following once set, I will try to forget Stop start hysterisis for the ASHP compressor. This determines how cool the floor is allowed to get before the compressor starts (based on return temperature) and stop hysterisis how long the compressor runs, and final flow temp before compressor stops. Once happy with how that responds, getting the right balance between CoP and energy use (they are very different things) I will then fine tune the WC curve. Once complete it will automate itself without external interference.

I'm doing that at the moment, just installed Open Energy Monitor (ace system). Had a nice wet cool day today and currently about 9 degrees, so have been optimising cycle times at low loads. Increased CoP by 1 with a little tweaking. By shortening cycle times to get a more balanced on and off time. Will do a bit more tomorrow before it's too warm.

That's just it, you don't need it the same temperature everywhere. You can if you want, but our bedrooms are generally cooler than the living space, because we add less heat in the bedrooms, our ensuite warmer than the bedroom because we have additional heat in there, or as best you can in the same space. It's called balancing the heating system. Part of the basic system design. If you want the house the same temperature leave the interiors open an hour or two, it will mostly even out (even on an upside down house, single storey or x up x down house) if don't want even temps keep the doors closed. Very different (?) because you heat the top and heat stays there to a large degree. But nothing really special going on. So your bedroom are a degree cooler, good for you. Mine isn't the perfect solution, neither is yours. It for the OP to ask questions dismiss or include whatever he wants, it's their money, their choice. @PNAmble are you the thread police, or just a grumpy person. Difficult to tell.

Obviously I missed the point of upside down. I have UFH in the bedrooms, but doing it again, as I said fan coils would be better. Main living space UFH is good, generally cheap to run especially with a heat pump I started that way and it was a disaster. Low energy houses already place a strain on the control system of any heat source, split the house further to small heating zones just leads to short cycling and or a buffer and rubbish CoP without very careful design. One zone, no mixers or additional pumps, saves money, improves performance, makes it all easy.

You cannot assume you need to get pump curves from the manual. Calculate the head loss (system pressure drop) at yourq flow rate required. But generally they are not feeble. Keeping it simple pays off. At 9 to 12 degs outside, when the heat pump is running, the CoP is mid 6s. That includes everything electrical in the system. So way cheaper than gas or anything else.

Single zoned heating system is fine, multiple manifolds fine. You need to check the volume flow and head loss for the circulation pump. But we are on 300mm centres and have 7 loops in the floor plus a further loop for a fan coil. We actually have our floor loops turned up pretty high. So the heat is churning around 1m³ per hour. Once you have checked flow rates against pressure drop, if all is fine no buffer is needed and no additional pumps or mixers. Fan coils should run.fine a UFH flow temperature. Buffer is generally needed if you zone to the house to keep minimum engaged water volume and minimum flow rate for the heat pump. No you wouldn't Possibly less need for a buffer. But bedrooms and UFH is a waste of time. We have it wish I had just installed fan coils. You need to start with heating design then decide on a need for primary and secondary loops. Not the other way around. Start with you heat losses, then emitters, the then pipe to the heat pump, do you pressure loss and flow calcs, then you know where you are. If and I may - bad idea you will end up in a muddle.

Have you been and contacted a local borehole specialist? Plenty in Scotland

I have generally reused, if they look ok. Outsourced energy sell euro cones. Assume they are a standard item across all manufacturers.

Cut a furring strip to match the miss alignment nail or screw in place - foaming the gaps is a bodge.

What temp are you heat it up to?

We are using Rye Oils, Ceder Oil on our cladding and garden furniture. Cheep as chips, goes on easy, sinks into the wood well. Our first coat lasted 2.5 years in a very exposed location, just done a second expect that to last longer. They quite a range of products.

Why do the controls need automating? Heat pump are a low and slow machine, best left to their own devises. Set a WC curve fine time the running parameters if needed, then leave them too it. The more fiddling from outside the more they cost to run.

I think most do. You just have to try hard to find some settings or combination of settings to suit each home and heat pump

That was my point, why bother getting two heat pumps, when LG will do both hot water and cool or heat. Seems like you are spending twice.

Sounds good, so just a bit of fine tuning really on the UFH mixer.

Everything I have read or heard about them says they are good. Work well out the box. Seems to give a very CoP with little effort. A few on here use then @Nickfromwales sang their praises also.

But this is based on thickness of material - as thermal conductivity is per metre thickness of material. So actually looks like the chat bot is talking sh*te - like they mostly seem too.