Thorfun

I predict £2 million. with all those curves and curved glazing and cantilevers with a grand designs finish it's gotta be at least £2.5k/m2. then add costs for **** ups along the way.

https://www.granddesignsmagazine.com/grand-designs-houses/grand-designs-new-series-2022/?utm_medium=email&utm_term=&utm_content=READ MORE&utm_source=Grand Designs Magazine&utm_campaign=New TV series coming soon! Here's what to expect... I'm particularly interested to see how a three-storey, 5 bed, 7 bathroom curved cantilevered 700m2 house with an initial budget of £700k turns out! 😂

all joking aside, I wish I could help. we did originally have light wells planned for our basement with walk-on glazing at ground level but in the end decided that it was just too expensive and those rooms in the basement didn't need natural light so I never did any real research on the subject. good luck though, and I genuinely mean that. 🙂

well that's a first!

I can recommend getting one of these first https://www.screwfix.com/c/tools/tape-measures/cat831176

so you have a 3 phase electricity connection? is your PV inverter 3-phase as well? I thought that if you have 3-phase electricity you can get 3.68kWp array on each phase so, in essence, 11kWp without G99 application. we have a 3-phase electricity connection but I was lucky and the DNO approved our 10.5kWp array AND a Powerwall 2 on a single phase so I don't have the headache of net metering for running the house as that will be on a single phase. only issue might be if/when I get a 3-phase EV charger then I'd need to ensure that net metering was working.

@Wil do you have DNO approval for 2 x PW2s? I know that @pocster wanted to put a second PW2 in but the DNO wouldn't allow it so had to go with a hybrid PW2/StoreEdge solution which he's been having a few teething issues with. I'm inclined to agree with @Dan F and suggest a single PW2 for now with only the 5kWp array and see if that works for you. if you find that you need the extra PW2 then take a look at it. £7400 pays for a lot of electricity especially when it's currently only 7p more than the E7 rate. if you had a larger PV array and could use the sun to fill both batteries then I'd say it would be more worth it. ultimately, it's up to you! and whether you're completely hung up on the whole 'pay-back' period. personally I never considered that when I plumped for our 10.5kWp array and battery solution. it wasn't about pay-back period it's more about reducing my reliance on the grid.

cheers and, yes, it's going in a GRP cabinet. sounds like a fair compromise between cost and quality. I was thinking that either the Lewden or the Contactum would be the ones to go for as a middle of the range type unit.

our electricity supply is on our boundary and the plant room about 25m away, as such I believe I need a switched fuse isolator installed in the cabinet (confirmed by my electrician). I've been looking at my options here and the price difference varies dramatically! e.g. https://www.gil-lec.co.uk/hager-jfe310u-fuse-switch-tpn-enclosed-100a - This Hager one is £450+VAT https://www.cef.co.uk/catalogue/products/4920299-100a-tp-n-metal-fused-switch - This Lewden one is £278+VAT https://www.electricaldirect.co.uk/product/contactum-100a-met-tpn-fused-switch-disconnector-648206 - This Contactum one is £205+VAT https://www.electricaldirect.co.uk/product/ced-100a-3-phase-tpn-fused-switch-disconnector-671368 - This CED one is £156+VAT I haven't included the ludicrously priced Eaton units! Can anyone please tell me if these are all the same in terms of quality and safety? We have a TT earthing system if that matters as my electrician says that due to the resistance of the TT system we would be hard pressed to ever blow a 100A fuse and we have 2 options with the TT system, 1. RCBOs throughout (my chosen method) 2. a time-delay 100mA RCB. So, if we're never likely to trip the 100A fuse why would I want to pay large amounts of money for a Hager isolator if the CED one does just as good a job?

it better, coz I ain't taking it off! 😉

It’s not installed yet so I can’t comment on the performance yet. Do a search on Pylontech and you’ll see others’ experiences.

Just FYI, the system I bought was around £4k + VAT (parts only) if that helps. 6.4kWh storage that is very expandable if required. Simply plug another (or more) battery in to get more storage others have also gone down the Pylontech route which offers similar results/costs.

I was quoted £9500 + VAT in March 2022 so could be anywhere upward of that by now! also, you won't find one for love nor money. I was quoted 12 months lead time. I did post a news article alluding to changes coming with Powerwalls later this year so maybe stock is so low because they're getting ready for a new model? or maybe at least a change on the PW2? if you're dead set on a Powerwall then maybe wait a few months. I decided to bin the idea of the PW2 and have gone a different route.

send your plans to MBC (or other TF companies that offer the same product!) and ask for a quote! they have in-house designers who should be able to translate your existing plans to a TF house afaik. it might add a small delay but the build is so quick with TF that you'd probably make up any delay in build time.

our architect designed a window that didn't work. it was floor to ceiling(-ish) overlooking a flat roof but they didn't take into consideration the insulation of the flat roof and so the window was below the level of the deck. in the end we had to build up the level in the wall to be above the roof and order a new window (only about £700 for us as we managed to tag it on to the existing order that hadn't shipped yet). we made a hole in a wall in another part of the house and used the original window there. so it wasn't wasted money for us just an extra expense that we weren't expecting but on the plus side we had another window looking into the woods surrounding us! I, not once, thought to sue or claim for the expense of that window from the architects but I've been told that I'm too nice! I also didn't want to sour our relationship with the architects over that amount of money. I felt it was a small price to pay for a minor inconvenience. obviously, for you it's a lot more money so would be harder to swallow the loss and a much bigger inconvenience! I can't advise whether the architect is at fault but it sounds like their disclaimer covers them. I guess you need to figure out if the legal costs for pursuing the claim will make it worthwhile if you believe you've a chance to win. people make mistakes and sometimes just need to be forgiven and move on. good luck with whatever you decide to do and it's a shame that this happened.

welcome! sounds like you've been at your renovation as long as @Onoff has been doing his bathroom. hope you find the information that you're looking for. it is a great source of knowledge.

🤣 take a look at the MBC passive house twin wall system with pumped in cellulose. according to those that have them they're VERY quiet internally as the 300mm cellulose really dampens down the external noise. (other companies are available to do this sort of twin wall pumped cellulose build)

I would suggest leaving your architect on good terms so they can be there down the line if you need to ask questions or get support. This is what we did with our architects and it was something they were happy with. they got us through planning and BC drawings and then let us get on with it. but they're at the end of a phone/email to discuss ideas or ask question etc and we have a really good relationship with them. I send them updated photos of the build and invite them to site to just look around without asking them questions so that they maintain an interest in how it's going. seems to be working for us really well. I would get rid of the QS though! once you have their figures on what things 'should' cost you can go out to tender on your own and will have an idea if the builders/subbies are trying it on or not. we used an online QS which gave me a ball park figure and was good enough for the bank to get a mortgage with. I then went to various groundworkers about building our basement and foundations. spoke to timber frame companies about building the timber frame. window companies for the windows. chose the best quotes/people I'd most like to work with (as that bit is very important if you're project managing!) and got on with it. that got the superstructure up and I then found subbies to do bits and pieces as we require them. I'm finding it quite stressful but also very enjoyable at the same time. yes, it's slower than using a main contractor but I'm learning loads, putting in the graft on site to save money and getting the satisfaction of actually self-building rather than calling it self-building and handing it over to someone to build a house. 🙂 with a job that requires a couple of days a month I would be all over self-building/project managing/getting involved. it's a great learning experience. but, I also agree with @Iceverge and, after spending months insulating and airtightness-ing it might've been worth while getting a TF company to do all of that. I'm sure we've saved a LOT of money (I'm thinking at least £10k and will calculate it once I'm done) but we'd be many many months further on in the build and a lot closer to moving in. I couldn't afford the basement AND the MBC passive twin-wall house so chose to have the basement and do a standard open-panel TF and insulating ourselves in the end. I love our basement space and once it's actually finished it will be amazing! but, I have a slight regret over having it and life would've been a lot easier and quicker to build if I'd gone the MBC passive route. but then where would my cinema, music room and gym have gone! 😂 I also agree with @Nickfromwales in that you should just crack on. find a groundworker to do your foundations as designed by the structural engineer and while that is happening you can find a builder to build the shell and a joiner to do the roof etc. once you get the ball rolling it's not as daunting as it first seems. it's taking the first step on a new and unknown journey that's the killer. JFDI!

I learnt from the master

thanks. no progress in the basement except that one of the rooms is now a store room for stuff that doesn't fit in the existing house! there's been progress above ground but I'll save that for another blog post. 😉

this is true. we paid approx £1000/kWp for our MCS installation not too long ago and I think that the prices have gone up since then. still, using your maths above even at £1000/kWp I still think it makes financial sense, especially when the panels I bought have a 25yr warranty. so even if I get 20 years out of them with the SEG it's looking good!

and adding in the paltry £0.05 SEG for the exported electricity brings it down to £0.155/kWh. (assuming my maths is correct!) 🙂

we're you so happy with how they came out you ended up dancing on the ceiling?

I really like the way our house looks with the blinds down. but I am a bit biased!

cor...they're lovely! we went for standard Venetians so we can use them for privacy as well. negates the need for internal curtains/blinds.