saveasteading

I'm hoping that someone is going to say, yes that's obviously causing the issue. Or otherwise. And why this shorts when only one core seems to be damaged. Then I'm thinking I replace that portion of cable, preferably without taking down the lamp fitting because....it all makes work.... Can I sensibly cut out 1m and join with a box or a connector each end? I know one electrician who refuses to use sometimes, especially the push fit type.

I've done it. I fought through the cobwebs like Prince Charming, but the good news is the absence of clutter in that remote corner. There is rodent damage. Also a strange brown crud on the cables there. on the first photo we see both the lamp and switch cables. They run to a large connection box. The black wire is exposed over about 30mm but does not look to be nibbled itself. There are some more mouse nibbles near, to the left, but very shallow. I actually see more clearly on the photo than I could up close, but should have snapped it further back to get the focus better. The near, out of focus, bit looks worse than it did in real time. I'm thinking the brown stain might be wood resin dripping from above, perhaps in summer heat or from occasional leaks. Thus attracting nibbling. Then that water now gets into the cable? There was no sign of dampness but it has been very wet and windy and this is under the ridge and one drop might do it....or some of that resin has built up inside. I'd have thought that I'd have to see copper for any short but I don't know. No dead things. Lots of historic mouse (and some rat) droppings But the second dose of bait is untouched so there weren't many around. I didn't look in the connection box. Well, I lifted a loose corner and nothing was apparent. The cables simply drop through the lath and plaster ceiling. Nothing dead visible in the holes. The grey cables are long redundant. I'm guessing and welcome any expert or other input.

I just want to emphasise that. The people that sell them tell outrageous lies about them. Think of them on yachts. There is always a brisk breeze and they can only trickle charge a battery and run a few lights. Inland the wind is many factors less. Nobody fits them on high office block roofs any longer, even to tick a sustainability box. I'm remembering construction exhibitions 20 years ago where there would be ten stands with the things, and Architects started specifying them. I refused to price them into jobs and it was an awkward argument. All these companies have gone. Solar and very big batteries ok, esp if you design the building for minimal demand. But if it's £20k for mains, take it.

I respect your correctness. 1.6m or 1.7m would be unambiguous. I suppose the lesson here is that non- tech people are not necessarily going to use standard terms.

Any roof will lift off if not fixed one way of another. Straps aren't needed on a steel portal frame for example. But most houses are walls with a roof laid on top, and need tying, and straps spread the load nicely down the wall into timber or masonry.

They are having an overview in limited time, and will often miss something. They are not your quality control manager. Also they may assume that eg ties are still to be fixed. First impressions of your building are good and that may give false assurance that everything is done properly.

I've thought (and been reminded) of 10 other things I have to do first. Finish 'wordle and connections', compost heap, visit the big project, get cat food.....

Can you give us a sense of scale? It may be a very heavy construction with a huge glulam and oversized rafters.

I forgot to look at the walls when I saw the view.

Which is what we built on purpose. The stone wall has a recognised U value (0.6 springs to mind) , as does the gap, but not a lot. We built a stud wall of 100mm with membrane on the back and insulation in the gaps, then a plastic inner sheet. then the service gap helps too. A recognised solution and working really well.

Memory failed on the colour, but it was that side so was the left hand black one. The switch to the right that is off may be confusing things (The one with the tag against it) It is another matter altogether. An outside light circuit that pings in wet conditions. so it is turned off. Helpful. I would be looking for such, but why would that short? Exposed wire but the top one is not touching or near any other conductor??

It is a standard construction and cracks are normal. You pack the gap with stones in lime mortar, using as big stones as you can fit in , then smaller so that the mortar is minimal. Must be lime, with the grade selected to be just softer than the stone. Granite/ limestone/ sandstone?? removing the mud and replacing it with masonry is advisable, as long as it remains stable all the time. Do you think the crack was there when they hid it behind the stud? The absence of rubble on the floor suggests it was. Is there a crack on the other side?

It needs long straps by Simpson or equal. These. And lots of them tying the roof down to the walls. Not that the wall looks very strong either, so the ties must go down to the cross beam/ lintel and then that needs fixing down at the ends. Someone should have specified them by type, location and fixings. Worrying that nobody seems to have done so. Wind uplift forces are scarily high and you genuinely could lose that roof. Do Not take any brackets off.

I like the buckets analogy. Struggling with the hill though. Isn't heating or cooling the same process of bucket passing? Downhill for poor insulation, uphill for good? You mean that it can be woven from rock or glass or paper or oil, but the gas or air bubbles and maze of conductive routes are what matters?

No It's been ok for 30 years....and nowhere near my recent overflowing header tank (resolved 3 weeks ago anyway). Also nobody has been near that area. The switch is well clear of any water source....the fitting I will check when I venture up. Tomorrow is always a good day for unpleasant things. Removed without benefit. correct It is 30A. As 4 family members have just left along with many chargers, I've checked again but it still trips. Anyway, they would be on the sockets ring main not the lighting circuit. Much confused though as 2 switches tripped at the same time. Isn't that like a rope or chain snapping in 2 places? surely one part breaks and the other doesn't? DB3 the left switch, along with the red switch on the distribution board (or am I misremembering already and it was the adjacent black? ) I put some special food in the attic a week ago, and then more. There was scampering until 2 days ago. There is no smell of rotting rodents but they may have gone elsewhere to be tidy. Mice smell 3 days, rats 5 days. So tomorrow I will put on my new favourite wooly hat with lamp in front (highly recommended) and get up there. I believe I am checking the ceiling connection for damp or dead things, and the cable from light fitting to switch, looking for teeth marks????

A normal sized house doesn't need one, and the ancillary heat from pumps and tanks etc is in the house, so not wasted. If you do want one it never has to be as big as plumbers and electricians say...it's nice for them at your cost.

Take this photo to your local builders' merchants or plumbers' merchant. Not screwfix, toolstation, b and q. They will sell you the necessary few parts including flexi hose.

Agreed there are other considerations, including vapour. The geometry is often overlooked too, with any extra thickness clashing with the eaves or requiring a gable oversail. It's one of these questions where we don't know enough, and expert professional advice should be taken.

I forgot to end my post with this. Insulation anywhere will reduce heat transfer. You could put some inside and some outside and less heat will escape. If it's outside then the cavity will get less cold. But bricks have resistance and so does enclosed air, so it all adds up.

If it helps anyone, here is the Woozle principle that can be applied to almost any Mechanical Physics. In this case it is a heat Woozle. (WZe?) Imagine a warmed up Woozle in your living room. To me they look like a yellow emoji figure with 2 arms and 2 legs. It is trying to escape out to the cold, wriggling through microscopic gaps in your wall. Thus any resistance works whether inside or outside or in-between. Area of less resistance ( whether universal or local) allow easier escape. There are other factors eg condensation but that is a slightly different analogy. 😳 I can't find one with limbs. Some day I will introduce the pulling and pushing ones that make beams work. It isn't my theory. My wife was taught about Woozles at Uni by a prof who could communicate, and she told me. Often used by me.

That sounds like the introduction. I trust the detailed study will be published on here. Flavours, pack sizes, and any trends through time.

@SteamyTea wondering if you could continue your instructive, with reference to the photos. I don't understand why one pings rather than another, esp as the fault under discussion can trigger either. Switch in a room, up to the attic above where we would hope any damage is fairly obvious.

And knowledgeable. I've met some very ignorant roofers who don't understand lapping and flashing. Absolutely not a clue, and if was as easy to do it right as wrong. They were roofers because they didn't mind heights and the money is good. (And ceey few clients check the work). All the above advice is good....it must not leak at this stage. Post a couple of pictures and you can honestly say you've had it looked at by experts and they have to sort it and spray test while you observe.

Done that. It is a single light switch. I haven't ventured into the attic yet as there are children around for a few days.

Somebody will be more up to date than me. But it is going to be something like £500/m of perimeter and a huge amount of mess. Why does it need underpinning?