Alan Ambrose

Apologies for yet another tank question. My objective is to get a more energy efficient set-up. In my 5th floor flat there is a 30-year old vented set-up. It has two big custom made cube-like tanks (almost 1m cubed each) tight in a cupboard and two Stuart-Turner 3 bar twin pumps (hot and cold) for pressure - one for each bathroom. (Some time, way back, I had a second one installed so we could shower even when one pump failed.) The upper vented cold tank is about 1m off the floor and there's a hot tank underneath, with thin-ish insulation and heated by two immersion heaters. (This was from a time when designers were scared of gas in flats and the flat has electricity only.) The incoming pressure is about 1.5 bar and I'm not sure whether or how often the mains pressure dips under that, but my upstairs neighbour has been having some trouble with mains pressure. I've applied a bit of extra insulation to the hot tank but it's not possible to get all around it and the temperature still falls off quite rapidly. (I've a Heatmiser system and can see the temperature fall-off quite easily and accurately.) I know the fall off is much faster than another more modern unvented set-up I have data on. There are some fancy taps and shower fittings here which need a minimum of 1.4 bar. So the question is, how can I get a better insulated system without risking dodgy water pressure? The options seem to be: (1) Replace with a more modern vented set-up with immersion heaters and keep the pumps. (2) Replace with a more modern unvented set-up with immersion heaters, lose the pumps and take the risk on low water pressure. (3) Go a bit off-piste and use something like a 12KW Heatrae Sadia electric boiler, lose the pumps and ditch all the tanks. Take the risk on low water pressure. I think a downstairs neighbour has something like that set-up. Any thoughts? Alan

@joth - so you have radial 12V, 24V and 'active' PoE into each room? Goodness 'PoE' seems a mess atm. Did you consider 5V for charging or is that a step too far? Any recommendations gained from your experience of doing all that - or is that just the best solution? Alan

>>> What do you mean by centrally switched LED lighting? Something similar to joth's set-up rather than direct mains light switch -> light bulb wiring Yeah they need to work, but Quinetic switches which sparkys are using to avoid tricky cable runs are part way there. Loxone more so. Alan

Well you always get good answers from this forum and often from a number of perspectives. I'm planning on running CAT cable everywhere which I guess means PoE everywhere, also centrally switched LED lighting, also sensors etc (e.g. Heatmaster) on radial circuits - all back to a plant room. I'm sure there will be PV batteries - maybe in the plant room, maybe not. So, that seems halfway there without trying... Alan

That sounds interesting, is it possible to describe a bit more? - central PSU for 24V? - PoE from one place only? - what kind of wiring / cable / fusing etc for the 24V? - you have your LED strips all wired back to a central smart switch somewhere? TIA, Alan

It seems to me we'll have more and more extra low voltage (5-48V) stuff as time goes on and I'm wondering whether anyone has considered wiring all over for that as well as 220V? There is a bit of thought here: https://www.theengineer.co.uk/content/product/dc-energy-metering-applications and https://www.mdpi.com/1996-1073/11/9/2463 which suggests maybe a 20%-ish saving. Particularly helpful where we already have 48V batteries for PV? Any thoughts? Alan

Yeah I can see the 'more is better' argument for 3-phase - more amps innit. But... + 3-phase is harder to monitor if you're into circuit-level power monitoring. Not impossible, just more expensive and fewer options. + the electricity companies are not really up with 3-phase domestic. Ask me how many meter-replacement men turned up here with single phase meters here (two). Once I got their boss out, he actually suggested I could usefully convert the property to single-phase. Duh. I imagine I'll wait until all the single phase smart meter roll out has happened before anyone asks why the remaining properties haven't got smart meters yet. Hmm, why would that be? + the whole idea is to be using less energy, not more . I have 3-phase where I am now, but I'm planning that single-phase will be fine for my new build - because it'll be 'new overhead line time' if I need 3-phase. Alan

Building control are usually quite happy to answer any questions in advance. Alan

Maybe find something vaguely similar on Etsy (say a light made with similar materials) and see if they'll custom make what you want? This is for your western-themed parties? Alan

Hi, Yeah, for work done in the last 10 or so years (i.e. since the DNO was established) there should be docs. For work beforehand, my understanding is that there may have been no docs (I'm talking LV / 230 or 400V) or that the docs might have been lost in the mists of time. Here, the latter is the case i.e. no docs. Alan

Hi, I have a question re re-routing overflying cables. But it boils down to this: ‘does the DNO have rights to enter a neighbour’s land to inspect the DNO’s poles & cables?’ Could they, for instance add a new stay? I’m pretty sure the DNO can’t find the existing wayleave agreements - even if they once existed. In fact they probably couldn’t find their own … well never mind. TIA, Alan

Thanks Chanmenie, >>> Company called Subteno From their website, they look like proper engineers . >>> but I do completely understand having someone local to oversee things and if there was a local SE that specialised in insulated slabs maybe I'd have given them an opportunity. but, as with a lot of things in the building game, that's not how they've always done it and so I didn't find any. Understand - I've found that once you start looking at more specialised skills, there may only be one or two in your county - and that's if you're lucky. Alan

Call it belt and braces, but I would much rather the SE attended site once or twice at the critical phases to ensure that what is being built is what he or she intended. I'm seeing a few comments like this on buildhub, so I'm not alone: >>> A few hundred pounds spent with a local SE, who knows the ground conditions in your area would be money well spent. >>> ... included two sites visits after trial holes were dug also included drainage design. So, I'm not alone. Alan

@Thorfun - I see a lot of people are happy with TSD. I wonder how any SE signs off on the build though if they don't observe the construction? Also, since it's much harder to sue a foreign company, what would you do if there was a major problem later? Or am I worrying too much? @Chanmenie - Yeah that would be great. Thanks, Alan

He he he, loved the video of the suspended digger Batibouw Trade show in Brussels sounds good. Alan

OK makes sense.

As title says . I'm leaning towards RC / Sika Watertight / KORE or similar. TIA, Alan

Hi, I think I figured out from our local authority that 'access' is simply highways visibility splays, driveways etc. i.e. vehicular access arrangements. Alan

Hi, We're at the planning application stage. It occurs to me that during the build and while we've got various trades on-site it would be nice and fairly low cost to build a smallish workshop and greenhouse etc. From the point of view of planning acceptance, would it be better to do these as permitted development after the whole building is finished and signed-off or is it OK to include them up-front in the planning application? I'm a bit concerned that they'll just give the planners something else to shoot at. Alan

Pert-al-pert pipe maybe although I don't understand the difference between that and PEX. A.

Yeah. I'm going on Friday. They don't have a very good way of figuring out which exhibitors you want to visit do they? No exhibitor maps, dodgy exhibitor search facility etc. Properly lazy IMHO. Alan

Hi, I was in Greece last week and you can't go anywhere without seeing simple solar thermal everywhere (the kind with the horizontal tank at the top) and also chunky motorised sun blinds that can withstand a bit of wind. I noted Iskios and Floros as manufacturers of the blinds and Dimas as one of the solar thermal manufacturers. Are we missing other good ideas and products e.g. from hotter or colder climes or just countries that have taken a different direction? TIA, Alan

Ah thanks Peter, Alan

Hi, I am trying to work out the foul water falls which I think are quite tight. I know the invert level of the destination and the drainage distance and the ground level at the building, but what is the minimum depth of the pipe near the foundation? I've seen references to 300mm to top of pipe and less when concreted over. Does that sound right? Also, is there a sensible minimum depth given you would prefer for it all not to freeze up? TIA, Alan

Wow, I just looked at PVGIS - it's fantastic Alan