PeterW

Chat to Wagner The APsystem micro inverters are good, as are the JA Solar panels. They do the IFRS in roof system so could probably sort the whole lot as a package, with the 3 pairs feeding the 3 flats.

For the cost - and if you have the space - I would put 6 panels on in 3x2. You can get a dual micro inverter that takes up to 600w, and that would give some baseline load for probably £2.5k all in. Offsetting the cost of the clays too will be significant.

I’ll go against the grain and say it’s a bad idea ... Stainless here would need to be quite thick, and you would need a serious mesh to get good adhesion (purely mechanical) to the the steel. Materials would be more than a former, and given you want to also tile it there is no real benefit over mild with 2 coats of red oxide. You could manufacture the same in fibreglass for £80-100 at most and do it in situ.

Is that per unit ..?? That’s only 3 panels in honest, would be nice if you went the GSE in roof route too as they actually work out nearly as cheap as tiles and look a lot nicer. TBH I would use micro inverters on all of them - one per panel - and then run to each unit and forget about it. Quick, simple and only one isolator in each build.

What is the final build up of the walls then..?? And 75 panels ..??!! Is that a typo..?? Start with someone like Wagner Renwables or ask @Nickfromwales for his contact.

I’ve done a spreadsheet that shows you how the different duct sizes affect flow, and takes your MVHR and does a very crude balancing and validation of BRegs values. I’ll post it up

No benefit of thermalite as they are designed for thermal performance. Mediums are cheap, easy to lay and quick. Make sure you ask them to point both sides too as nothing worse than a blockwork wall full of half filled perps

Sorry - what noise ..??! That’s my question. If its to stop the sound of someone snoring, the materials need to be different to that of a higher pitched whine for example from machinery. @Moonshine didn’t you post something about sound absorbtion..?

What sound insulation are you trying to achieve...?? A solid sealed door may actually transmit sound not block it - MVHR helps where you have the flow between pairs of rooms such as an en-suite into a bedroom etc.

Looks nice - I'd echo the comments from others though. Move the downstairs toilet to opposite side where hall cupboard is, and put a coat cupboard under the stairs. Hot tank upstairs could come downstairs too. I see your architect has drawn a beautiful open corner on the family room with double sliders etc .... Before you commit to this, just get a structural engineer to have a look at that design as I think you will be in for a fright. The dotted line between dining and family room already shows where there will have to be steel, but with such a huge opening - 4m x 4m...?? - the cantilevered steels to support the corner of the roof will be significant, the remaining roof steel and other components, notwithstanding the £10-15k for the windows alone, will be significant. Consider a brick, steel or other column now, and you will save a lot of heartache when the numbers come in.

It’s still wrong ... as @Carrerahill says, this should be two steels, one for each leaf as I said earlier. SE needs to sign off but I would not top load a flange like that, it’s asking for trouble.

What was the engine in that then as the original Hudson was a 3 wheel Renault 5..!

So this is for an external wall that is becoming an internal wall..?? if it’s 2 storey, I can’t see how 203 / 203 UC will work as it’s supporting the whole of the back wall plus potentially the floor joists and a wall plate. Who did the steel design .

I agree however adding 325mm to a 203mm means it’s got a 162mm or 81mm each side overhang. If it is a cavity wall, then that means 80% of the load will be on the other edge of the flange which is well past the advised loading on a steel.

@JSHarris is that a Hudson ..??

So at a worst case, assuming 3 large and 3 small ICs, 30 bends, 6 hoppers, 80m of pipe, plus 10 tonnes of Gravel, I’m getting to £1650 give or take.

Hmmm.... Is that an external wall he’s taking about as that will create a horrific cold bridge. It will also give issues with boxing in, and the Structural Engineer will have something to say as you’re adding an additional dead load and torsional load to the top flange. He is suggesting that 20mm of steel welded on site (assuming its two on top of the top flange) is strong enough to take the load of the wall above (which I expect is 100/125/100 block/cavity/block) and has ignored the strength of the flange itself. If there is a wide wall, usually the engineer will detail a pair of steels with either bolted or welded together to ensure there is no twisting. I would ask for calculations first.

Yep - I’ve installed a buffer in the circuit so have 60 litres of tank as a type of low loss header to allow the UFH to draw as much or as little as it wants in the way of water at 38c depending on the return temps.

Ikea do a full mini kitchen for about £450

Fit a 4x2 head wherever the studwork will be onto the rafters then board either side of it. Quicker to work around a ceiling than with walls in the way. You could also swap your timber for metal stud at that point too if you wanted.

Are we just talking 800mm trenches here ..?? should be less than a load of muck away (assuming treatment plant is in..??) as you should only be getting a cubic metre of spoil per 8m of dig out if they use a 300mm bucket. What is the detail planned for the bottom of the downpipes..? Is it gulleys with shoes, or straight into the ground..?

Trigger happy architect there. Don’t need half those ICs drawn. Only odd thought is that if you have no rainwater harvesting tank, where is the soak away as that seems to run to a grass outlet ..???

Welcome Quick question - what’s happening about building regulations ..??

Its one of those questions - have they not taken these designs into production as the costs would outweigh the benefits...?

Read my response carefully then comment please. To get anything like a decent capacity - such as 200 litres of usable hot water - you need to use either a UVC of 300 litres at 55c, or a thermal store of around 425 litres due to how they heat the water. That’s a big ass TS to get not a lot of DHW capacity. I expect the Ecodan you’re using is one of the PUTZ units that has its own controller. If you read the technical manual ( I have) and also look at the control algorithms (I have) and then look at the on off cycle of the compressor vs auxiliary heater (I’ve done that too..) you’ll find that it uses a secondary aux heater to get to 55c so your CoP is around 2.1 at best when it’s 17c outside. (Somewhere around page 32 of the manual). At 7c outdoors it’s 1.6, -5c it’s around 1.2. For reference, that’s a pretty crap score and makes your ASHP solution for hot water roughly 30% more expensive than mains gas ... but what do I know ..?? ASHP is not designed to heat to those temperatures unless it has either an auxiliary heater - ie an immersion element - or uses a type of compressor that can create high output temperatures which is at the direct cost of flow volumes. Lower flow volume = longer recovery time. So yes, Mitsubishi do know what they are doing, but I suggest you read the manuals and understand how they actually work before commenting please.