ProDave

The left hand switch is definitely wired for 2 way, Red, yellow blue of one cable. That may well be on a different circuit. The middle and right switch are on the same circuit and connected to the second cable. Red is live feed looped to middle and right switches, blue is switched output from middle switch, yellow is switched output from right switch. The complexity of your alteration has just gone up somewhat. There are no junctions at the switch so it is either wired "loop at light" or quite likely spider fashion where everything goes to one great big junction box often in an unknown location. Apart from locating that junction box, your biggest issue is no spare cores in the existing cables to use for the 2 way switching of the outside light. At this point I suggest you find an electrician, this might be beyond remote diagnosis on a forum. Somehow you are going to have to get an extra cable to that switch and it looks to be plastered brick or block so that means chasing a new cable into the wall and the re plastering and decorating afterwards. If you choose to proceed I would install a new cable and wire the entire outside light as a complete new circuit.

The cable up the wall needs to be in trunking, conduit or why not just continue the SWA up into the loft and just have one junction box in the loft. Yes the terminology is very confusing estpecially as "gang" has 2 different uses for 2 different things. So Gang. You can have 1 gang and 2 gang back boxes. 1 gang is square for a light switch or single socket, 2 gang is rectangular for a double socket or 4 way light switch. You can have 1 2 3 or 4 gang light switches meaning the number of switches, where a 1,2 and 3 gang light switch fit in a 1 gang back box and a 4 gang light switch fits in a 2 gang back box. Clear? Switches, a simple on off switch is often referred to as 1 way. It can turn a single light on and off from one place and has 2 terminals. 2 changeover switch has 3 terminals and is often referred to as 2 way. It can be used just like a 1 way for a single light, or a pair of them can be used for 2 way switching. Why anyone makes or anyone bithers to buy a 1 way switch beats me, a 2 way does everything and only costs a few pence more. Then there is the intermediate light switch that confuses most people even more.

The bit inside the house does not need to be SWA. But you WILL need 3 core plus earth from the light switch to the junction box where it connects to the SWA for the remainder of it's journey. Ideally could you unscrew that switch and post some pictures of the wiring inside? What I have describes is the simplest wiring possible but it may be this house is wired differently so it could be more complicated. The inside switch almost certainly will be suitable, it would be very unusual to find a 3 gang switch that is not 2 way. (3 gang means 3 switches on the one plate, 2 gang means it is a changeover switch with 3 contacts and not a simple on off switch with just 2 contacts) There is no single way to wire light switching so lets start with finding out from those pictures how this is connected.

The above post is good, but it does come back to how good the trades are, and were they recommended? Our builders first built the foundation to the plans. Then they built the timber frame. But they did not just build the frame from the plans, they came and measured the foundations, even though they had just built them, to make sure the frame was built to the size of the foundations. Later we employed the same builder to supply and fit the windows. Again they had built the frame to the drawings, but before ordering the windows they came and measured each window and door opening. We had no nasty surprises because they checked and re checked everything.

So you will want a 3 core 1mm Steel wire armoured cable from the house switch to the outside switch which will need to be a waterproof 1 gang 2 way switch. These are usually in a back box with knock outs for the SWA cable gland. Then from the switch 2 the light you only need 2 core but might as well use the same 3 core SWA to save buying 2 different lots. Likely you will need a junction box by the light as few outside lights can directly take SWA glands.

Are you prepared to change the cable between the indoor switch and the outdoor switch? If not you probably won't be able to achieve proper 2 way switching. Do you know how many cores are in the cable to the light? Post a picture of the wiring to the indoor light switch if you can and the cable where you want to add the outdoor switch.

If the AAV has failed and is letting air out, then it will inflate the plastic bad you are about to tape over it.

If you are a regular hill or mountain walker you will know there is no such thing as a minimum width for a public footpath. What is your "failure" footpath used for? I doubt it if for the home owners to get access to their back gardens. More likely for walkers to gain access to / from somewhere in the countryside. The only "complaint" you might have is if the actual right of way shown on the definitive map is further to the left in that picture, then he won't have just made it narrower, he will have diverted it to a different location. That they could take action against.

How long since last de sludge? Check none of the traps have run dry, just pour a bit of water down each to make sure. An AAV won't let a smell in unless it has failed but that is unusual. Try taping a plastic bag over the AAV's to see if that stops the smell?

We did this. Using a local company I knew and trusted (had worked with them before) but they did foundations and timber frame build and errect so it would be their problem if the frame did not fit the foundations.

Because they will, and are already doing so in some parts of the world. Again, if they are in other parts of the world, WHY NOT HERE. What is our government doing wrong that other countries do right? We NEED to change how we do it.

Most "ordinary people" don't analyse it and work out why, they just look at "results" We are being told more renewables will reduce prices. We have been set a target of how much they will reduce by the next election, instead consumers are seeing them rise. They better damned well fall by £300 by the next election otherwise it will be "yet another failed election promise, this lot are no better than the last lot, we need something radically different. Welcome PM Mr Farage." I don't support Reform, but I perfectly understand the frustration and despair people have with the 2 parties that have alternated in power all my working life and fully understand people like me no longer believing a word that they say. I really would have thought one of them would learn by now you can't just go giving the electorate a load of hopes and wishes portrayed as promises, and not expect the people to be a little bit annoyed at you when you fail to do what you promised.

The point is we keep being told by Starmer that more renewables will lower our bills. Now we are going to face a further (yes small) rise to our electricity bills to help pay for propping up the creaking grid. However small, that is bills going in the WRONG direction. And do you really think the master of U turns is really going to deliver £300 savings per customer in 4 years? Yes the electricity price determined by gas price link needs to end, but ALSO and much quicker and easier is to put the green levies onto GAS prices not electricity. Whoever came up with a scheme that basically says "we want consumers to switch to cleaner electricity rather than gas, how shall we encourage them? By taxing the cleaner fuel we want them to switch to insteady of the dirty one we want them to stop using"

Buttering us up for the U turn on "more renewables will bring bills down" Why am I not surprised disappointed ?

Do you mean 2.4m? That is low for the apex of a vaulted ceiling and would not be high enough for that sort of multi pendant fitting.

It makes me angry that the law says the CIL won't apply to self builders. So WHY are they allowed to make the system so complicated and with so many "traps" to try and make self builders pay if they don't tick the right boxes in the right order?

We have one light fitting in our 5M by 4M bedroom. It is a high ceiling with a light fitting that hangs down a long way with 3 lamps in it. Works no problem. How easy to change at this stage? What is above? Accessible loft space, easy peasy. Vaulted ceiling with just a small service void could be very difficult.

I assume some sort of hand rails are still to be fitted? There is one lone wooden post in place at the moment suggesting that might be the case. I would have made them less wide, but perhaps they are that wide to allow an infirm person to use them with a helper with them? Agreed about the lack of edging, the grass will quickly encroach on the steps.

Why is anyone paying? I thought this was supposed to be covered by a government initiative to provide gigabit internet to all properties?

What was asked for and agreed? They are functional if not pretty. Of course the devil is in the detail that you can't see, what base has been laid under the grass to support them?

It's been plumbed wrong. The cold taps should be fed from the same pressure reduced feed as feeds the cylinder. Instead it sounds like yours are fed direct from the mains and since you turned the pressure down, as you say the cold feeds are now at a higher pressure.

The highlighted word is the important one. Judging by the way he butchered your wall I am not sure that word applied here?

"Summer bypass" is a poor description of this function. It is in reality "heat exchanger bypass" In summer when it is hot, the heat exchanger can actually work in reverse and COOL the incoming air. Operating "summer bypass" then, would just allow ever hotter air into the house. I have never used the bypass function on mine, I struggle to find the very few times it would actually be of any use.

You choices are get the kit and design for £0 which takes account of the grant, then pay your chaps to fit it. Or ignore the grant altogether, buy the kit yourself, pay your guys to fit it and get nothing.

One option to look at is a number of companies will supply the kit for free (using the BUS grant) with design and paperwork, leaving you (or your builder) to install it. Any competent plumber and electrician that can read the install manual will be able to install it.