ProDave

I have said before how in rural Australia, collecting rainwater from your roof is normal. MY BIL in Queensland has this, 4 big tanks that collect the rainwater from the house and barn roofs. And It is very nice pure water. In the dry season, if they run out they simply buy in a tanker full of water. @Onoff If you do install a new treatment plant you will need building regulations approval. Up here I am sure you also need planning permission, check if that is the case in England.

Here you go https://www.toolstation.com/electrical/switches-sockets/white-switches-sockets/c147?brand=Scolmore Click Toolstation do free delivery on a £10 order.

It is a LONG time since I regarded MK as a quality make, let alone the best (as they once were) I don't touch their stuff now. I have had problems getting cables to clamp in their terminals plenty of times., My favourite still remains Scholmore Click Mode, now available from Toolstation.

That seems normal practice. My BIL lives in a Welsh farmhouse, now just an 8 acre smallholding. He once said "the septic tank is over there, somewhere, nobody ever empties it and we don't even know for sure where it is" As long as stuff goes away when you flush, nobody minds it appears.

Again, no SDS. When drilling outside (lets face it you would not use this indoors) there is a high probability you want to drill brick or concrete, so SDS is pretty essential.

Don't tempt me. Price though. You can get any petrol power tool for under £100 and an SDS drill for £50. So why does sticking the gearbox of a drill onto the engine from a strimmer or chainsaw result in a £500 price tag? And it's only as wood drill no hammer action let alone SDS. 2 out of 10 for trying.

I bought mine through Carbon Dynamic, the company that did all the design work and drawings. They are local to us and they build modular houses in their factory. They were the local agent for both the wood fibre board and the render system that we used and the prices I got from them were much cheaper than anywhere else I could find. I guess the result of buying in bulk for their own use and selling it on with only a small markup. Before you go rushing to find them, they went into adminstration just before christmas and subsequently were bought by another larger building company. Now that they are under new ownership I don't even know if they would sell materials directly. I have not had any dealings with them since the change of ownership.

I would start by shoveling the "muck" off the top of what might be a manhole cover in the last picture WITHOUT standing directly on it. If it is a manhole cover, remove it. If it is full of brown smelly stuff, get a man in to pump it all out before you go ANY further. I get the impression it is behind the house so might be a long way from the road. You might want to have a measure and warn them what length of suction hose they will need from the tanker to the manhole. If that cover reveals the smelly stuff, probe it with a stick and see if it is really "the pit" or just another blocked inspection chamber on the way.

If you decide to look at the filter mound I might be of help. This was our original proposal so I did the research and designed one. The sand for it, being graded, would have cost about £1000

Green and beehive shaped is almost certainly the BioPure. Same as @JSHarris has. Sounds seriously dangerous prodding about in your "slurry pit" I wonder how deep it is if you did fall in? Could be fatal. take great care.

For me it has to be petrol as it gets used away for home and I just dislike batteries and the fact they don't last long (I would have a petrol cordless drill if someone made one)

There is a type of 110mm soil pipe fitting that is a really acute sharp 90 degree bend, sharper than a normal bend. I forget what it's proper name is, but I got one from Travis Perkins when I needed to offset the stack pipe and 2 normal bends would give too much offset.

My two favourites are Stixall which is probably the one I would use for this, or if all else fails, sticks like sh*t, but NOT the clear SLS.

So let me get this right. the only benefit was to them, and they want to charge you £50 if you want to continue providing them with data? I wonder how many mugs sign up for this?

Can you not just grip them with a claw hammer and pull them through?

At the time I bought mine, SIG (Sheffield Insulation Group) were by far the cheapest place to buy frametherm 35 from.

What access to the screws do you have? If you can see the shank but the head is fubared then just grab it with mole grips and undo it. If you want an oscilating tool, usually know as a multitool, and are not in a hurry, wait until next time Aldi or Lidl have them. I am happy with my £25 mains powered one from Lidl.

My only regret is that I DID use full bore isolators on the showers. It might have slowed the hot water usage if I had used smaller ones. We get 15L per minute on he showers at full flow.

I must admit I found SSE to become "hostile" When I registered my G83/2 install they initially thought it was 4KW not 3.68, and told me I had to apply for permission to connect it and sent the application form. The tone of the wording seemed designed to put you off as there was talk of a charge to provide a quote and that charge would still be payable if you did not proceed with the quote. I found it very intimidating.

I wish they would go into a bit of detail about the structure. e.g one built with block on the flat (to give lots of t****** m***) So what insulates the building? It appeared to be bare block inside so presumably some insulation between the block and the cladding? It would have been nice to know.

I forgot, you are on the Llangollen canal aren't you, one of the few that does have a small flow. (very noticable when going the "wrong way" over the pontcysyllte aqueduct)

For me the reason to have taps / valves, is you can turn on circuits as you connect them, e.g our en-suite is not yet done so that one remains firmly valved off at the moment but when we connect it, we just have to turn it on.

A structural engineer is a designer. He does calculations and produces drawings from which someone else makes them.

Yes Frametherm is perfect for the job. It is flexible yet stiff enough that when pushed in between the rafters of a roof, it just stays there. My comment was about his suggestion to fill the frame with slabs of wood fibre. Those are not flexible enough to squash in.

Re your foundations. You need a structural engineer and he will come and witness some test holes being dug so he can see what the ground is, and design foundations to suit. On a Welsh hill above the snow line. This sounds like an old Grand Designs where they could not even reach the plot for most of the winter, and at one point a spring appeared in the hill above them running out and through the house. Best of luck!!!!