MikeGrahamT21

Plenty of ways to meet insulation standards of today, not sure a whole load of steel is very ecological or economical, but as you rightly say you can add internal wall insulation, as long as you achieve the stated U value requirements with your build up then you are good. Just don’t forget to have the cavity pumped with blown beads too!

Isn’t the 3m3/m2.h number related to this… It’s talking about carbon emissions rather than overall efficiency, of course the lower the ACH the better it will work but also doesn’t mean it won’t work at all. https://www.passivhaustrust.org.uk/UserFiles/File/research papers/MVHR/2020.04.27-The Case for MVHR-v7.pdf it is expensive though, I’ll give it that!

I go into panic if I’m spending more than £4 a day 😬 but then I think that’s more part of being a Yorkshire man!

I suspect you’ll probably need a G100 compliant export power manager style device, to limit your export to agreed limits

What size, type is your property and how well insulated is it?

A chimney breast will have zero issues holding 25kg, an almost negligible amount given the load capacity of a double brick chimney breast. your fixing strategy is over the top too, a fixing either end would work fine, and I’d probably up that to three (one in the middle) to stop the timber sagging. Don’t bother glueing the timber to the wall, as you will only be glueing it to paint/paper. the majority of these pre-made timber mantles actually hang on the wall much like a picture frame

If your BCO are like mine, they haven't a clue what MVHR even is 🤣

You shouldn't need to change the flow rate, thats what the actuators are for. I don't have actuators on my manifold, and have to turn the clear plastic tube to alter the flow rate, but yours definitely don't look like mine. Probably worth a call to nuheat, or see if they've a manual online?

Yes absolutely, they sell kits for this which will come with the relevant butyl seal. im sure if you can get the glass dimensions you could probably do it even more DIY for much less by ordering the glass (ensure correct spec) and a roll of butyl seal. you’ll need to buy the same dimensions as it has currently, I think they did used to sell a triple glazed upgrade for the older windows but it only resulted in a 0.1Uw decrease so probably isn’t worth the extra cost

From memory the Redland 49's are slightly curved, they look like Marley Ludlow Plus to me, which are flat from top to bottom

How are the bills from this year vs last year?

I too have had this over the years, I can only think that the paint isn’t as flexible as the caulk, but I don’t remember it doing this many years ago so something must have changed either in the caulk or the paint makeup. I don’t have an answer for you though, I have just repeatedly applied paint until it covers it up, but it does take some goes to get rid of it completely. any decorators on hand to help?

Compatibility for the battery BMS, but as long as you follow the battery specs you can always setup your inverter in a custom config to match it. LiFePO4 are not the kind of batteries you find in e-scooters, they are currently the safest ones you can buy, but that’s not to say they are perfect. if you are storing it externally, you need to also consider environmental factors, heat moisture etc, far better for the battery to be in a constant environment. I’ve had my pylontech batteries in the boiler cupboard for 4 years now

The onus for any regulations is always on the home owner, though the builder/roofer should have advised really. I wouldn't worry about it, you can try and get a retrospective one, at least everything the BCO will need to see is more or less visible, or as others have said, a simple indemnity insurance policy when/if you sell

You'll need a G100 compliant inverter, some of the Solis ones are properly compliant. There are also export power managers which sit seperate as the G100 device, Solis also do one of these, but i'm not 100% how they work, as i don't have/need one. They'll probably enforce this too, so they'll come out and do a compliance check.