ProDave

It might be good point to point out that whilst it is strictly speaking legal to DIY your own gas work, you must still be competent to do that work. Be very careful.

I wonder if the CH flow rate has dropped and you are getting localised boiling (kettling) inside the boiler?

Remind me not to let SWMBO see this thread.

There is the issue of saleability and mortgagability. You probably won't get a mortgage on a "caravan" and it won't be worth as much as a proper house even if extremely well built. No possibility to extend later beyond the size limits of a "caravan" The 3.05 metre height is the ceiling height inside. You can put a proper pitched roof on it, you just can't use the loft space for accommodation as that would no longer fit within the definition of "caravan"

You are right that if you can't get planning for a "proper" house you can fall back and build the maximum permitted size of "caravan" And the legal definition of caravan is such that it does not even have to be on wheels, just movable in some form and that may involve the use of a crane. There is also nothing stopping you making a really well insulated "caravan" as good as any house. There was one such featured on Grand Designs a few years ago. The other issue is you may not be able to reclaim the VAT. You normally need a building control completion certificate for a VAT claim but you won't have that as it is exempt from building regulations. That however may free you up to do things with the layout that would not be possible if you needed building regs. I assume all services are connected already? If not, you will need building control for the drainage work.

The best you can do is sleeve them yourself. I used the outer sheath from some old coloured tails that were going for scrap

What insulation levels do you want? I wanted a pretty well insulated house, better than the standard offerings of most of the timber framed companies. I tried talking to them about taking a standard kit and adding extra insulation, they then refused to quote. I ended up paying a local eco house builder to design what I wanted, and then paid a local firm of builders to make the frame off site, and bring it to site in sections and erect it. I am now doing all the detailing and fit out myself.

LPG use different flexi hoses to a mains gas cooker. Go to somehwere like BES to get the tight hose and they sell the fittings for it to plug into if you don't have them For instance here is a kit with the hose and the fittings https://www.bes.co.uk/micropoint-gas-cooker-installation-kit-no-4-lpg-16175

For my money, Triton all the way, cheap, reliable but not fancy, If your water pressure will support it fit the largest power you can find.

Yes I stand accused. Poetic license, I know my switchfuse is wired "wrong" I would not do it like that for a customer. I would run the inner cable of the SWA up into your consumer unit intact and distribute the earths using the earth bar in the CU. Only taking the gland earths direct to your main earth terminal.

The key difference is how they store the heat. With a UVC the water stored in the tank is the water that comes out of the tap. Of you heat it to say 55 degrees, then when you turn on a tap, water comes out at 55 degrees and continues to do so almost until all the hot water is used up then goes cold very quickly A thermal store stores it's heat in a static volume of water that never changes. You draw water via a heat exchange coil. So as soon a you start removing heat it starts to cool down. So if that wa heated to 55 degrees, the hot water would start at that, then start reducing in temperature. So you will in practice have to heat a thermal store hotter to get the same amount of usable hot water from it. The advantage of a thermal store over an UVC is the lack of requirement for over pressure valves etc and need for discharge pipework, and in theory at least you need a qualified plumber to install a UVC.

Yes, I think I will be making my own liners. Thanks for checking the market and confirming still nobody makes it in the right sizes. I used all flush hinges in my last house (except for the fire door) but thought you would call me a bodger if I suggested that.

Just to be clear. In my picture those are insulated AND sheathed cables, it's just what the cable the DNO's use up here have colour coded sheaths. It was the markings with the sharpie that he got wrong. I have installed my own rod already.

the meter monkeys round here just seem to use a white sharpie and don't always get it right

Hi and welcome to the forum. Make sure you have a good solicitor on board that understands plots. Check the planning permission. Measure the plot to make sure it is what you think and the house will actually fit. Check the services, water, electricity and in particular drainage. How will the services get to the site and from where? Easements etc. And re drainage, if not mains, what system is proposed? will it actually fit? will it actually work? These are more fundamental to get right first. Then you can design the house that suits your needs.

I too don't like the double deck Henley's. Just one thin web of brittle plastic separates them. I much prefer two singles side by side, some makes even interlock when so arranged, but much more substantial separation. But they are in now so I would leave them. You are not supposed to strip the outer sheath outside the enclosures. If you want to check the colour you take the cover off.

I would just drive a small grid tied inverter to feed into the mains. the sort of thing that's very cheap on ebay, at say a constant 50W or 100W thinking it's better to just offset the base load than just heat water with it. Alternatively if I do make a solar PV battery storage system it would just charge those batteries.

Okay, I am on the verge of ordering my stairs. I thought it worth listing the options I looked at: Pear Stairs came in at £900 for the basic price, that was before I started tweaking things that were outside the scope of their on line design tool, so very likely to have risen in price. TK stairs, I could not get their on line design tool to produce the staircase I wanted. I got close but had to fudge it. The basic price was coming in at £799. I contacted them with the saved quote and a list of the changes I needed to get it to a final quote. A week later they have not replied. Stairbox of all of them had the best on line design tool. Read into that the only one that could (almost) properly give me the staircase I wanted. The initial price was very keen. So I got them to tweak the few things I wanted changed (just short dwarf newel posts, and a slightly longer going at 260mm giving an angle of 38 degrees) I was initially a bit peeved when that pushed the price up another £150, but they are still the cheapest at £811 inc VAT and delivered The local joiner wants £1420 plus VAT. So it looks like Stairbox will be getting the order.

Why would you link it to your DHW? Assuming like mine it would be very low power, it might as well just generate 50W or so of 240V and offset the base load. It would be rare not to have that much in use in the house ever.

The (almost) finished item The stove is a cheap Chinese Kresnick from woodburner world, 4Kw I don't expect it to be particularly efficient. The granite slabs it sits on are offcuts from worktops I got from freecycle ages ago, at last I have found a use for them. The back one and the one up the side of the unit have an air gap behind them. I just lit some cardboard in it just to make sure it draws okay, better wait for that fire cement before I fire it up properly. And here's the flue. It's raining now and it doesn't seem to leak.

If that's in your garden I would definitely be doing something with it. I will one day have a play with a generator in our burn but at only 1 metre head I won't get much. An undershot water wheel may work better in our situation.

I will leave my options open. I won't put the ceiling cover plate on until I see in practice how hot the outside wall of the top twin section flue really gets. It's yellow looking old style bare glass wool.

Next question, when making the hole in the roof, do I have to treat the glass wool insulation in the ceiling as "flamable" and cut it back further? or is it okay for the glass wool to touch the outside of the twin wall flue? (I am guessing glass wool is not flamable but want to be sure)

I have that adaptor, that's there after the two 45 degree bends but I have not yet fitted the locking band to clamp the sections together. One small tub of black fire cement ordered from CPC £2.54

My flue-pipes.com flue arrived today. Heavily over packed and on pallet, and delivered in a 30t truck that had trouble with our little road. But very quick delivery It all looks good and as I expected. Now I am just starting to piece it together, I have one issue, the interface from the stove to the first bit of pipe: The 2 45 degree bends fit together snug as they do into the adapter and into the twin wall. But where the first bit of pipe fit into the top flange on the stove, it is a loose fit, probably 2-3mm all round. What do I fill it with? Fire cement? fire rope? or some high temperature sealant out of a gun?