ProDave

The bottom of that hole is not very level.

As we now know the not a passive house, then you need the heating on until probably 8 or 9pm If it goes off at 2pm it is no surprise it is getting a bit cool in the evening.

If your studs are 300mm centres (check, that seems very close) then you cut the frametherm to 300mm wide. At 300mm centres, the gap between them will be more like 255mm so the 300mm insulation will squash in and be a tight fit.

Looks like it has bottomed out for now? https://www.boilerjuice.com/heating-oil-prices/

The frametherm 35 comes on 1 1200mm wide roll. you cut it to the width you want with a panel saw while it is still rolled up and wrapped in it's plastic wrapping when it is easy to cut. Most of my studs are on 600mm centres so you simply cut each roll in half.

The rules are different under Scottish regs. We have to provide a "circulation space" of either a 1500mm diameter circle or a 1400mm by 1800mm elipse in a kitchen. That effectively means two opposing runs of kitchen units cannot be less than 1400mm apart. No doubt the English building regs are different, that is where you have to look.

EPC C76 is far from being a passive house.with a primary energy need of 29,406kWh per year.

The switchmaster appears to be obsolete. Are you SURE it's not working right? the way 3 port valves work is to hold them mid position they switch from ac to dc powering the motor, and a bit of hunting backwards and forwards until they settle, with the mid position switch clicking on and off is normal.

It will make noise outside when heating the hot water, but you should be able to time that when you are least likely to be outside.

About as noisy as an oil fired boiler burner. the difference is the noise is outside so won't bother you. Most people are happy to have an oil boiler roaring away inside the house.

OIL

The only complicated thing is the control unit most ASHP manufacturers supply. They are needed for setting up system parameters like flow temperatures and options. It looks as though that setup has a conventional central heating type programmer next to it. This is what I normally do and did with ours. Although you can usually set timing functions with the ASHP programmer, they are often fiendishly complicated and nobody understands them. So having a conventional heating programmer just for the on off timing makes a great deal of sense, Then you never need to touch the ASHP's own programmer other than for curiosity. Make sure the installer records in the instruction book ALL the parameters that they have changed from the default settings.

It will possibly enable a smaller cheaper manifold, save a few ££ in pipe and labour fitting the unneeded landing loop. We had that in our previous house and I don't believe the landing thermostat ever turned on.

Multiple loops per room is normal for large rooms. the control centre is organised so that room thermostat opens 2 or 3 actuators together. I don't see loops bridging more than one room, other than pipes passing through on their way. e.g your downstairs hall by the stairs is never going to be cold. From experience, you will NOT need an UFH loop on the landing. Delete that one.

@AnonymousBosch has got the "falling through the joist" badge already.

Those default settings are "weather compensation" so when it's -5 degrees outside it runs the heating at 55 degrees, but when the outside temperature is 15 degrees the heating will only run at 35 degrees. In addition there is a thermostatic mixer valve on the UFH manifold just under the pump. That will regulate the maximum temperature that is delivered to the actual UFH pipes. It is normal to have a thermometer somewhere near the pump to see what temperature you have it set too. You can get a good idea how hot the UFH water is by just feeling the pipes going down into the floor. Anything less than 40 degrees will feel cool or tepid. If it feels "hot" it is probably approaching 50 degrees. The big tank is the HW tank, the small tank is a buffer tank for the UFH. It looks a well done instalation.

That was the first one I found to illustrate the point. I am sure I have seen it in push fit as well.

You can get a version of that grey tripple socket that has TWO boss connections side by side and hence is a little longer. Might that do it?

We have ours set to come on at 06:00 and off at 21:00 When on it's under the control of the room thermostats. What temperature is the water flowing in the UFH pipes? Is there a temperature gauge on the manifold? (I think that is a pressure gauge at the right) Low temperature UFH will only heat up slowly, that's why ours comes on at 06:00 Is the house really passive house standard or is that an off the cuff statement? I am not sure what the controller is saying when it says "outdoor 50 degrees"

[smug] it's actually a civil service pension in all but name. Paid by the treasury and with no "fund" to back it up. (so no fund to crash in value) My other small SIPP is sitting as cash because I was nervous about the markets even before this, so is worth exactly the same as it was. People kept telling me I was missing out on dividends by keeping it as cash. Well I am glad to have missed out on a 30% or more drop in it's value. [/smug] Of course the government could enact legislation to stop the early drawing of a pension. When I signed up to this at the start of my career it had a fixed retirement date of age 60, it was only quite recently that the ability to draw it from age 55 onwards came in.

I am still working until I get some symptoms that make me self isolate or until told otherwise. At the moment we are still being told to go to "work" The phone has gone very quiet recently. I suspect when all my jobs in the pipeline are done demand will drop off as people decide their jobs can wait to save having potential carriers in their homes. If things get desperate I do have a fall back that I could start drawing a pension that is due in 3 years time. It is available to me any time, so who knows this situation may actually trigger me into retiring a bit earlier than I had planned for.

My concern would be finance. If you have the money to pay for it then great, but personally I would be very concerned at taking on debt right now.

A bit like a motorcycle accident. DO NOT remove his helmet.

Our island is completely free standing. It's sheer weight ensures it is not going anywhere. Though it may be "helped" to go for a bit of a walk after completion sign off, when silly circulation spaces might not apply any more (cough)

I will just get on with building the house. There will be the garden to tend to soon, and next winters firewood to start chopping and stacking. Then there's Building control for a temporary habitation certificate and a VAT claim to submit. I wonder how BC will cope with that if they are locked down? Would a trip to the boat class as "essential travel" as long as I promise not to go close to anyone else?