JohnMo

You can do this with double glazing, but you frame has to be very good. Double glazed panel krypton filled, will give, approx 1.2 for the centre pane. But you may struggle to get double glazed bi folds that achieve this. Any triple glazed should be able to beat this though.

From the weight and area of glass, it should be two sheets of 10mm

I used double sided tape for my offcuts. As the main strips had this when I bough it

I just bought a salus quantum, very slim on the wall, rechargeable and around £70

I like to think of it simply. Coil for heat pump, coil for solar thermal. Set ASHP Stat as suggested at 48/50 degs. Base case, ASHP heat tank to 48 deg. If solar heat availability is there, have a separate thermostat, to allow tank to max heat the cylinder will allow. You can achieve this with an unvented cylinder or thermal store. Next question is do you need a buffer for your heating? If so, this could use the volume of water within the thermal store as part of the heating circuit. A two port valve and pump controlled by your central heating thermostat. Your heat pump only has to heat water in tank, no sanitiser program required, as DHW flows through a coil in the thermal store. Why do you need to monitor water temp at different heights?

My niece had an electric combi, and binned it very quickly due to the huge running cost. Electricity costs around 3 times the cost of gas/ lpg per kWh. Without a cylinder you options are limited

If you want a storage heater look on gumtree, people give them away, not new but... Maybe worth a punt

Unfortunately PV doesn't generate much electricity in the heating season, so using it for heating may not be very successful.

Not sure, generally putting wires in insulation isn't a good thing as you have to up the sizes of the cables - but why not use wireless, with wireless control centre. A lot on the market can now be recharged, so no faffing with batteries.

I've got an Atag combi, it seems well made, nice and quite. They do a system boiler i24S also

Our windows (which are much smaller) had to be approved by the structural engineer due to wind loads, would have thought that size sky light would need someone qualified to approve the design. 1cm X 1cm glass is huge, if it hits you. I would get professional advise. They have said the risk, so the responsibility could fall on your shoulders if all went wrong. I landed via a ladder fail, on glass side tables, the glass was all over the floor (6m X 6m), the shares as as sharp as a sharp thing.

We have semi flexible 90mm via plenums, and we are the best part silent, that with Scottish building regs requirements of 0.5 ACH, compared to England which I believe is 0.3 ACH. We have two MVHR Units, to enable short runs and low pressure drops, this keeps fan speed down, even on boost we are only at about half max speed. Keeping velocity through ducts low, fan speed low all contribute to low sound levels.

They would only guarantee us 6.0mb Went 4g can get between 12 and 40. Had to buy modem at £100, then £35/m free mobile calls on landline phone and unlimited data

Voulted ceilings depend on the design, our lounge is voulted, to be non voulted I would have to install a ceiling, so that is a cost adder, we are in a bungalow, so the loft would be huge and mostly a waste of space. With the voulted ceiling the airtight aspects were easy also. In fact all the ceilings match the roof line, it made the build simple

I would make appointments with a couple of local architects, I wouldn't bother if they are or aren't passivhaus experienced, unless you want it certified. Get a design your happy with, number of bedrooms, living space etc, then work on the thermal aspects. And also how you plan to build, method and if self build, turnkey, main contractor, or sub contractors under your control Decide early if you going single storey or two storey. I would say "fairly involved in project management", may not work for you or who is project managing, as you will end up stepping on each others toes. I would either project manage or let someone else. To project manage you need to be there a large amount of time. It may also depend on how you are building, turnkey, they may not even allow you on site without an appointment?

I wouldn't like to embed copper pipes as you say with joints, Pert-al-Pert or similar would be better, a manifold would be easy enough. You could almost run it like UFH, but with radiators. Assume the upstairs will be bedrooms, do you like the same temperatures in your bedrooms? A thermostat in each bedroom, would enable you run slightly cooler temps in one or more rooms.

I used a brush and shovel, don't overthink it

I added until I had a double cream thickness

Big gaps, sand cement. I did a parge with a thin cement mix, for this I used 3 sand (not sharp sand as it's too gritty), 1 cement, and about 1/5 lime. Applied with a broom.

You have air in the loops, from the sounds of it, UFH should be near silent

Thinking about it, under screed pipes they have to be installed in such a way that makes it possible to replace; hence the conduit. If you have joint below the screed, it cannot be replaced, so will not comply with Building Regs

Not greyed so far, overhangs were mostly completed in March, the rest finished in August, will get the last bits completed in the next couple of weeks. It wasn't kiln dried.

It's shiplap, I think

It came from Timber Central in Nairn