Tom

Agree this is a good idea, but how would this work in practice on a time+materials basis? What's to stop the builder inflating their time costs to cover for this? Is snagging only something for fixed price arrangements?

Thanks onoff, have I not got a neutral/earth fault based on the tests so far, and I'm assuming there is no way to find where on the ring main this fault is?

Checked all sockets and can't find anything. Unfortunately the cables run in the walls so can't check them. Just typical this happens a day after moving in, I guess must be us moving around or plugging/unplugging things must have shifted something. Is the only option now a new ring main?

ok, just tested and continuity between neutral and earth (0 ohms) and no continuity between live and earth/neutral. I guess that's what we expected?

Hmmm, a multimeter and one of those screwdrivers with a bulb in it and that's about it! Would it be worth investing in one of those plug-in testers https://www.toolstation.com/socket-tester/p82826 - though TBH unless there is a fault easily accessible in the socket there is no way I'm going to start pulling the walls apart, so might as well cut my losses and just run a new ring main under the caravan. I just wonder if there is something I'm overlooking though.... Absolutely nothing plugged in - so what else could it be?

Good point, but I think one of the factors being that I can potentially work/labour as and when I can and bring the costs down, which I couldn't with a fixed price Is the RIBA template aimed at fixed price?

The tenders were very detailed as it happened - just very expensive! They were based on the full set of drawings from the architect - one builder said he'd never seen such a comprehensive set of drawings. We didn't provide any more information than that TBH. No CIL where we are and building regs approved on drawings. We're just south of Totnes - whereabouts are you?

So we hope to start our build in the next 6 weeks or so. We have had a few fixed price tenders back which are way over budget so they are a non-starter, a local builder we know has built similar and is convinced he can bring the project in for what we need, and has suggested a time+materials arrangement and we've decided to go with this. We are going to meet up again in the next few days to sort out more details etc but I'm wondering if any one has any advice on what details we need to nail down at the start? I'm thinking: - rough timeline, so we can get some idea as we go along if things are slipping, costs going up etc - payment schedule: weekly? monthly? in construction stages, foundations, walls etc? - retention of final £X% for snagging etc? - what if I'm not happy with something - some sort of agreement on rectifying without cost to myself? - site insurance - some sort of commitment on hours/week? - I don't want the build dragging on as it's being used to fill in hours around other jobs etc Is the above reasonable? What else? Thanks all

So, got a replacement RCD yesterday... no change. Worth a gamble I suppose but hey ho. Worked out what the problem is though: its the ring main. What I had done when I was testing it before was only remove one side of the ring main at one time, rather than both (slaps forehead). Should have read your post more carefully Dave! So, I have completely disconnected the ring main from the first MCD and the others now work, so at least we have lights. Still stuck trying to work out why the ring main is faulty though. Nothing is plugged in so I guess it has to be an earth fault in the wiring. Why should this suddenly happen though? The ring main wiring is run through the walls of the static rather than underneath so can't get at it. I suppose I can check all the sockets for a fault there but if that draws a blank I will have to rewire a new ring main I guess and run it up through the floor to new sockets. Any other ideas?

? on a tasty FIT so definitely reusing!

Thanks Dave, don't worry, I'm more than aware of my own limitations (which are legion, according to the wife) so wont do anything silly. Your lights wont start flickering as I fry what remains of my hair.... There's a good chance I'll be passing a TLC tomorrow so if I can pick up a like for like replacement rcd I will do, if that doesn't work or I can't find one I'll call a sparks in. There is one coming soon anyway to remove the PV from the barn and move the various consumer units to a temporary location for the build, at which point I'll get a proper supply to the caravan sorted, so this is only tempory. I'm being careful though and won't do anything stupid.

Would this do the job? https://www.toolstation.com/axiom-incomer-devices/p65443

The caravan is effectively a spur from the barn. Just thinking: is there any point measuring the resistance between the neutral and earth rails in the box? Presume should be high unless there is a fault?

one more... do I need to replace the rcd like for like or are they a generic fitment and I can just get the same ampage?

Was working fine, but then went. No digging and no chaffing. Would a supply fault to the caravan cause the RCD to trip though? The RCD in the barn from which it is connected is not tripping. Just having a look now at the board thinking I might go through it and test again, but cannot now switch the RCD on at all. All MCBs off.

The lighting MCB trips it when I switch it to on true, but I can switch the other two MCBs on but then any load on those trips it too. So can it be a fault on any one circuit? No extractor fan in the loo (unfortunately). There is no earth rod for the van itself, but the supply is from one of the barns via the 3phase supply to these - it's a 16a cable. I've already tried replacing this as I was initially thinking it must have been a fault on the supply.

So pondering this while lying awake at 3am last night: if I AM able to switch the RCD to the on position (even after a few tries) then it cant be a neutral/earth fault? As irrespective of the MCD position it should trip straight away - is that right? It seems to trip when there is load on any of the circuits - a neutral/earth fault should trip the RCD irrespective of whether there is load on a circuit or not. So it MUST be a faulty RCD?

Thanks Dave and thanks Tony - great video. So I've tried removing each wire from each mcb in turn, and their corresponding neutral (and earth, though rereading your post Dave it looks like I needn't have bothered, makes sense when I think about it). Anyway, makes no difference, the RCD keeps tripping when I turn an appliance on, heater on or flip the lighting mcb (guess there must be a slight load on this circuit). A lot of the time the RCD doesn't reset even if all mcb's are in the off position. It takes multiple attempts and then it will finally stay on. Faulty RCD? 20210220_190356.jpg

Pic attached, remove wires going in to the top of the mcb?

Yes please Dave!

All appliances and lights off. I turn on the RCD and can switch on all 3 mcb's - but drawing any current on any of the 3 mcb controlled circuits- e.g. turning a light or any appliance on, trips it.

Moved in to the static yesterday. Cosmic. All going well, or at least as well as can be expected. Today electrics fine, but then suddenly this afternoon the rcd trips and won't go back "on". I turn off the three switches in the consumer unit: lights, ring main and heaters. I can turn the rcd back to on, but if I turn any of the three switches to "on" it trips again. I'm guessing there can't be a downstream fault in the three circuits as any of them trips it, so there must be a fault upstream in the supply to the consumer unit - is that right? Help!! At the moment sat here with an extension lead from the barn powering our router and a light...

Thanks all. Looks like that one on aliexpress you link to Temp needs a wired connection to a router, then you can connect to that via a 4g phone... So, might go for the lo-fi option to start with a la Russel Griffiths: clear signage, while I sort something out with ducting for a wired/powered solution. If I was to put in a 100mm duct how deep should this be laid? Does it come with something running through it to allow you to pull wires through?

Hi all, so we're actually (finally) moving on to site in to our static caravan next week. The mechanics of actually living there are beginning to become more pressing issues now, not least the fact that our site is approx 200yards down a farm track which in wet weather is quite slippery. I'd like to install a video doorbell thing at the end of the track - what options do I have? It seems all the Ring-type things need wifi connection which isn't there. 4G signal is reasonable but I can't find a similar set-up that will work with this. There are security cameras that will work over 4G (https://reolink.com/gb/product/reolink-go/?attribute_pa_version=1-pack-white&gclid=EAIaIQobChMIrIiZr9nh7gIVE5ftCh3_WwyaEAYYASABEgITd_D_BwE) but we ideally need something that we can talk through like a RIng so we can direct delivery drivers etc. I could potentially put a data cable along the track - would that work along 200 yards+? Any suggestions gratefully received.

...and in addition to what has already been said, I have always understood that you have been allowed to partially demolish, but not if the intent was to put this back up later i.e the structure remaining after demolition is what is being converted, and as such has to be capable of being so.