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Why? If you were searching for a way to lower costs or saving construction time/effort then that's one thing. But I don't see how doing something custom here does anything other than add cost/stress. If you are paying someone to fit this they will want extra to accomodate you and this may void any warranty. If you are doing it yourself you are added extra mental load and work to figure this out when you are going to have a huge number of other things to deal with. Given this is the overlap between the solar install and roof install doing something custom risks needing to ask both the solar installer and the roof installer to deviate from their standard practice. This will add cost to both, add extra time to negotiate, etc, etc. If you do decide to do this, will you actually notice any difference whatsoever once it's done? Looking from two stories down on the ground?

Back when I first found this forum I caught up with Jeremy's blog using the wayback machine. I assume it still works if you try that.

I may be wrong with this. I went to check and read plenty about keeping a border around the panels but coming up blank finding a regs requirement. Might be something to do with MCS or specific mounting systems.

That looks good. On a real roof you couldn't do this exactly as you need a walkable area for regs AFAIK (the systems that do edge to edge use special panels designed to take the load). If I ever get to build I've been wondering if its possible to do something similar but with added metal trim around the walkable area/spaces to make it look like an integrated roof without the added cost. GSE is an alternative but I like the idea of being able to replace the panels with next gen ones without having to redo the whole roof which GSE would require if you can't find panels of the exact same size.

I'd be cautious about intervening here. Right now it's between your installer and Ofgem. If you start getting involved it muddies the waters if this ever ended up in a more formal dispute. Talk as much as you want with the installer but if you start sending stuff to Ofgem or start a separate registration process could be taken as you interferring and harming the process (even if the intention is the opposite). As long as you didn't miss a request for info from the installer and the lack of progress is purely down to the installer then I think you should tell them it's not your problem and leave them to sort it. You won't pay for their negligence. Could hint at complaing to MCS (look up the rules and refer to the specific relevant bits). Communication should be written not phone calls.

I've been watching the Restoration Couple on Youtube and their self build. When they had some welding done on-site the welder did something similar as a matter of course. The test itself shouldn't be expensive, having someone come in separately to do it would be.

If you can find a blank for that rather than a fitting (either male or female - assuming that right angle is the same diameter/thread at each end) you could always get one of these and tap the plastic (you'd need the tap too of course): https://www.airsupplies.co.uk/npt-male-stud Still, the question keeps being asked, what are you doing? If you are just using a big tank as a water source to feed a pumped irrigation system then don't bother with any of this just get a submersible pump and put it in the tank with the little hose attached. Or, see if you can't find a different outlet/drillable boss on the tank to use rather than this huge fitting.

Stupid ugly quick option: Buy/find a short length of hose that fits the barb and a barb to male BSP adapter, ala: You could probably find a reducer that goes straight from barb to your tiny hose though if you look. What are you actually trying to do? Going from such a big outlet to the piddly hose suggests maybe need to go back to the drawing board.

In practice yes, but roof integrated panels do cost more due to lower volumes. Especially, unusual styles such as those bonded to standing seam metalwork. Personally I wouldn't want to go anywhere near that style of solar as AFAIK they don't use glass bonded panels rather some plastic/flexible style which are far less battle tested (and generally have a bad reliability reputation where they have been used). Fixing any issues when the panel is bonded to your roof structure is basically impossible. @flanagaj I'm sure I read something from you before suggesting you were on a very low budget, like £1500-2000/m, am I remembering correctly? If so, I can't see how you are going to get this build over the line if you are letting yourself get drawn to some of the most expensive options.

Alternatively the switch might just leak a bit of current even though its off. Measure the resistance of the switch in both on and off states with nothing else connected.

Have you got this switch connected via a relatively long wire? (Significantly more than the shelly was designed for - which I think is very short wires) Wire is probably picking up small current from somewhere thats not enough to change the shellys state but enough to hold the switch high once triggered (at least for a time - if you wait long enough it might reset). If a resistor works then you can play with the wiring and see if you can fix it.

If it's an active-high circuit. ie, when voltage is present home assistant reads 'on' then wouldn't a pull-down resistor be needed? ie, there is some stray signal pulling the signal up which you want to override. Would have thought a 10k resistor would be a better starting point than 1M

A dry shake floor is something I'm very curious about for if I ever get the chance to build. During your research did you look at https://concria.com/ ? They seem to be selling their solution as quicker/easier to lay and a more reliable outcome. Recently Sika bought a big share so there must be something there. Curious on any thoughts/detail you can share. In any case please come back with the outcome when you get that far.

Oh now I'm confused. Am I thinking of someone else? I thought you had a heat gain problem in the bedrooms even during heating season so wanted the ability to cool the bedroom while the downstairs wanted heat. After I read that I looked back at some old threads and thought I read about how to do that you had to install a second zone with a big buffer tank to give the zone enough volume to avoid cycling. Have I misunderstood something?

Have you completed the details fully to come up with the number or just the basics? I don't know the app but I note that the heatpump efficiency is marked at 100% in your screenshot. In reality a good install should be 400-500%. You need the detail to be correct to get good output. I've seen many on hear saying they initally got bad numbers but once all the little details were added it came out better. SAP is still a flawed system however.

What dimensions are you working to? Is this an integrated unit or just a bespoke slot for a standalone unit? If the latter, maybe a slightly smaller unit would work with some extra trim?

The different warranty providers do sometimes have additional requirements that go beyond pure building regs. NHBC definitely does (but doesn't really deal with self-builders). LABC have a large guidance doc that should be consulted before using them for warranty. Don't know about others. They don't want you doing things that have a high history of claims, even if it is building regs compliant.

It's probably more complex than this but I thought it was mainly: 1. Solar Gain 2. The temp difference between outside and inside (same calculation as with heating) 3. The amount of air infiltration/exchange (same as with heating though might be additional focus on humidity) The solar gain is the difficult one which is why if you are mainly north facing with some east facing windows (that already have shading) you might not need to worry too much about this. If you are south facing with no shading its a huge deal.

Interesting point. I assume banking on the 30 min billing windows as a benefit to single phase (because if you aren't generating enough solar you are using grid energy anyway?).

I thought that was sorted now. Roll out started about when you were getting one and is now in full swing?

This isn't exactly correct. The grid acts as a buffer and your electricity meter counts net generation. So you can generate on 1 phase and consume on another without being charged. Assuming you have a modern smart meter. Obviously you aren't strictly directly using the energy that you generated but I doubt that matters to anyone unless you aim to be off-grid, or expect long grid outages. A reason for three phase is that it's easier to export from larger arrays as you get 3x16A automatic export allowance, and it will generally be easier to get permission to go bigger if equally split among the phases. Agree that inside a house the need for 3 phase is minimal. There are some uses (big cooking appliances) but other than that and it's not much needed. Having the flexibility to install EV chargers or power a workshop are nice though.

Modern heat pumps are inverter driven. This doesn't present an inductive load (or at least nothing like a traditional motor). They will soft start,

Ok. that should help a fair bit. Also, I noticed your main room is on a north-east alignment. Assuming thats where the windows are you should be limited in solar gain coming from the east (morning) so peak solar gain will be much more limited in time than a south facing direction. Shading will make a big difference and limiting the duration of max gain also makes a big difference. Look at the average over the worst 4-5 hours, not the peak. The floor slab should provide some buffer for peak load also.

Well since no-one else has replied. Any luck with this? I can't see it working too well as shown. BTW: that cable looks like it needs attention.

So what did the dynamic modelling show? I know that Part O isn't enough if you want to keep the place at a steady 21 but your numbers are suggesting >6kW gain into one room. Did it specify shading strategies to limit the gain? Have you accounted for that in your calcs above? 6.5kw is a lot of heat to put into one room (even if it is a big one).