ProDave

With that level of insulation and such a small space, don't fit a WBS, you will melt the first time you light it.

I have not tried the BG ones you linked to but I have used these https://www.tlc-direct.co.uk/Products/FB4235.html

If you have a proper void behind, AND if you have large enough wall lights, you can sink a round (conduit box sized) dry lining box into the plasterboard to accommodate a junction to flex. And check before cutting any holes, if you have said your prayers, you will find the fixing centres of the wall light match the round conduit box screw spacing.

That is pretty standard. I would use 1mm cable in that situation, though some electricians seem stuck in wanting to use 1.5mm and not open to reason. Of course you can strip the cables back to terminate them. But it looks to me like that is a plasterboard wall? If so leave some of the cable and push the spare back into the wall. You will thank me in 10 years when you want different wall lights and you need a bit more cable. Choose your lights carefully some can be a mare to fit more than one cable and keeping things neat and tidy is usually the key to getting everything to fit. If the lights are class 2 / double insulated, often they are the hardest to terminate as they require the connections to be contained inside a usually too small plastic box. Class 1 (those that need an earth) are often very much easier to connect and less demanding.

I would say three of the multiple fixings should be a nut and bolt right through old and new joists (one each end and one in the middle) them multiple screws as well.

Re overheating with your WBS. That is said a lot, and if heating a single room that is not huge that may well be so. But our house basically has 2 rooms either side of the entrance hall, each with double doors facing each other. So when lighting the stove all those doors are open so the stove can heat the whole house not just one room. Like that it will burn for a few hours nicely heating the whole house without any particular space being uncomfortable.

And don't waste time and money fitting UFH loops to the hall. When are UFH designers going to learn that. I was similarly duped and blindly followed the instructions in my first self build. There is simply no external walls to lose heat, so the hall and landing loops NEVER turned on. Complete waste. Sadly it shows lack of understanding by the designer which really puts me off. What is going upstairs?

The clue is in the writing on the right hand switch. It says "Kitchen switch" So leave the 2 in the cupboard always on. The tank will heat overnight on the off peak. Then IF you have used up all your hot water before the end of the day, you can turn on the switch in the kitchen and that will top up the tank from the peak rate. It saves you having to go to the cupboard to do so.

He also thinks carbon capture is a waste of time and is very pragmatic about what is possible. Not aiming for unachievable dreams regardless of cost.

Don't believe those figures. Just what is he suggesting that costs £4000 to get just 1 SAP point. I suspect your best bang for your buck improvement would be solar PV, very cheap now, and if you can't have it on your roof due to conservation area, ground mount it. The as built result will largely depend on details, like your actual air tightness test. That is mostly down to detail, not cost. How much will you be doing yourself? If you are doing a lot, you can take the time to get it right at little cost.

Well done. But why only aim for an EPC B. Aim higher, not hard to get an A.

We need Octopus's boss to replace Ed Milliband. THEN we might get some sensible policies. I have not heard anyone talk so much well reasoned sense for a long time.

The "cheaper source of electricity will reduce bills" is the Elephant in the room. Not until someone radically alters the way electricity pricing is calculated.

I would replace with this. https://www.screwfix.com/p/floplast-492015-mdpe-elbow-25mm-x-25mm/14096 Part of the locking mechanism when you tighten the compression bit is they physically dig into the pipe so there is no way they will pull out without dismantling the fitting. You First push the pipe into the fitting and you can check it has pushed properly into the O ring seal only then do you tighten the compression bit which ensures it is not coming out, pressure or no pressure. All my mdpe pipe is connected with that type of fitting.

Check it has the proper insert into the end of the pipe. Often missed out.

And my council tax is £1000 more than that, but unlike energy bills, I can't reduce it by switching "supplier" or making improvements to my house.

And neither is the claim that prices will come down as we have more renewable capacity. That has also been proved to be incorrect. It is a great shame it is our MP's that are still telling us these untruths.

A good "test" for internet dropouts is to stream an internet radio station. When we had ADSL in the bad old days, it would regularly drop out for seconds at a time. I said back then "whoever said broadband was always on was a lair or an optimist" Now we have decent broadband via a wireless (not mobile phone) connection, dropouts are extremely rare.

Just footnote to confirm smells should not transfer around the house. I had to paint some stuff with Hammerite recently and it was way too cold to do so in the garage, so I painted them in the utility room and kept the door shut. Stinky stuff Hammerite, but not the slightest whiff of it anywhere else in the house.

NO. It's the fact that the ridiculous energy market we are stuck with, prices ALL electricity at the cost of the most expensive which is gas. So even though from that graph gas provides less than 40% of our energy all of it is priced as if it were all from gas. We need a radical change to the energy market to stop this nonsense. Otherwise the promise of "electricity will only get cheaper with more renewables" will only happen when renewables reaches 100% and the last gas power station closes down. We are being conned / ripped off and most people are too blinkered to even notice this.

Our water comes from a mountain loch about 600ft above sea level, at this time of year fed by snow melt probably. We often joke why is it not coming out of the taps in lumps. We only get condensation on the cistern in the utility room when some washing is on the airer, temporarily pushing up the local humidity (spell checked)

Why don't you want to attach it to the wall?

My old digger had a LOT of play in it. It did not stop it working and it did not get any worse while I had it. I just used it and spent my time building, not fettling.

A typical cistern is about 6 litres. It would have to be very close to the HW tank otherwise the hot water won't have even got there before it is full.

8M by 8M by 0.45M is the volume you have to fill, so 28.8 M3 per side. So you either scrape off the top soil, add the infill then replace top soil, or for less work put a lesser amount of infil then fresh topsoil on top.