SteamyTea

Don't listen to that tosser, he just likes spouting off.

Assuming that internal space will not be compromised, just remove all the stuff, existing plasterboard, VCL and insulation. Make the sheathing as airtight as possible i.e. perfect. Then increase stud depth, reinsulate, VCL and all plumbing and wiring that needs changing. Sometimes it is just easier and cheaper to start again.

I have never measured a sheet of foam insulation across the diagonal, how accurately are they cut. Most 'foams' will shrink over time.

If the roof is sloping towards the south, have you considered solar, either PV, ST or both? PV is the easy and cheap one and could part charge, and sometimes fully charge a 100 lt DHW cylinder. But as you already have a 10mm cable, you can run a 45A load with very little losses ~1V. My DHW is a simple gravity fed, 210 lt, Economy 7 cylinder with a 3 kW heater in it. I pump both the cold and hot and have a good shower.

Not really, because as you rightly point out, our infrastructure is now out of date. Eventually there has to be some individual responsibility to help out the rest of society. It is why we have laws. If you take an easy, but poor argument, using a motoring analogy, I have never had an accident when travelling over 90 MPH, so why can I not always drive over 90? Even if I do have a catastrophic accident at high speed, the sum of the energies would still, probably, be less than all the lower speed accidents I have had. So on balance I would do less overall damage.

The combination of TF and blown cellulose insulation is very good for both thermal and sound transmission. Possibly the lowest mainstream embodied energy and carbon construction. (It is very easy to fudge embodied numbers, so take all of them with a very large punch of salt)

Because it is an undervalued resource that lottery gets flushed down the bog, which then causes problems downstream, literally. We spend, as a nation,a fortune treating waste water, much of it untreated rain water, so that it can enter rivers and the sea. When the system fails, usually because of excess rainfall, the consequences are quite extreme.

I use a small, cheap shower pump on my gravity fed system. Most people comment how good the shower is. Think I have about 1.5 m of head. Two things to be wary of us running the F&E dry, causing an airlock, and the more serious one if causing negative pressure in a cheap copper cylinder, causing it to buckle.

Being on the same level does not affect it. It is not a gravity fed system. Assuming your mains water comes in greater than 3 bar and there is a decent flow rate (this is the important thing really, the dynamic flow rate), then it should not be a problem. In reality we all need to use a lot less water, I use way too much at about 170 lt/day.

Say you considered the CO2 levels too high, apart from increasing that rooms ACH, not much else can be done about it.

The difference between SIP and TF is how the structural loads are distributed. Structural Insulated Panel Timber Frame There are many different ways to design with each.

I would have thought that checking the room flow rates and keeping the filters clean would be the best way.

Why not use a home made one.

There used to be (30 years ago) a quarry on Portland that could sort out just about anything. Just don't say the word "rabbit" as they are as mad as they come there.

You could knock up your own test heat exchanger. A simple pipe in pipe design would give you an idea of how much energy, and at what temperatures, you are likely to actually get.

Yes they should, but most CPD I have done (as a teacher/lecturer) was very low quality.

Yes, basically what the recent Grenfell fire report said. Unprofessional bunch of tosses.

I don't know, why I asked. But my car insurance cover the damage I do to others when I get totally shitfaced and plough into a building full of children, disabled children, some who have red hair.

Is this they type if thing that the builder's PI insurance will cover?

Meant to reduce noise by 40 dB or so, but that is very subjective (why there are different decibel scales). You can get acoustic plasterboard. Or headphones and slippers, all conversation by text. But as you get older, you go deaf anyway, and forgetful.

There was a statement from someone that at very low RPM/Phase Change pressures that the pump seals can fail. You also find that when the modulation i.e. pressure difference, is very small, the refrigerant condenses/evaporates in the wrong part of the unit. There is a lot made of gas boilers modulating to very low outputs, but I wonder how efficient they really are at the extremes. I can easily modulate the power output of my car by driving up a steep hill, in 6th gear, with my foot flat to the floor. Low power, extremely poor fuel efficiency. (on that note, yesterday I got 73 MPG over 550 miles, which is about 600 Wh/mile. Only about double what an EV uses)

Will it be worth more with a shiny coat on it.

Yes, just reread what you typed yesterday. It really comes down to your room by room heat losses, that will set how much energy is transferred between rooms/outside. Then you need to look at the most suitable insulation/sound proofing and floor finish. Sound proofing does not have to be 'all in the floor'. Plasterboard hanging from resilience bars can improving this.

Is that because someone measured incorrectly? The joists twist may or may not be a problem. Ideally the forces need to go directly though the web, the greater the twist, the less load the joist can take, which causes buckling. Buckling tends to be a catastrophic failure, not just a bit of extra 'bounce'. This is because as the sin of the angle increases, the sideward forces increase (or is it the cosine, makes no difference, it is the angle that is important). I would not be happy (structurally) with walls in the wrong place, twisted joists and brackets not fitted right. You seem to be doing the right things in involving the manufacturer, builder and possibly a SE.

Two houses, or two wives then. (I am actually not sure what I mean, is this about adding upstairs radiators to the existing ground floor UFH)