andyscotland

Brilliant, thanks @ElliotP hope you had a nice warm Christmas!

I don't understand how that's relevant. 708 section 5 is about output tax when a VAT registered entity sells a building either as freehold or on a long lease. So if your SPV is going to own the building and sell it to you, it could be VAT registered, reclaim the input tax (5% for labour / supply & fit, 20% for materials), then charge 0% VAT when it sells to you. But up-thread you said there's no stamp duty implications and it sounds like your SPV is just going to design & build with you as owner/client. If so then your SPV will not be selling you a freehold/lease so that section of the VAT Notice is irrelevant? Instead your SPV will be a "normal" service provider so will have to charge 5% VAT on all services to you in line with the earlier section of the VAT notice which as @Temp says you may then be able to claim back from the self-build scheme. But in the latter case your SPV would have to be charging you enough of a markup to show that the entity/VAT registration was for the purposes of "trade". And therefore you will have to pay corporation tax on that profit inside the company, and presumably dividend/income tax to get the profit back out of the company. Bear in mind that for the self-build reclaim (unlike business VAT returns) HMRC see & check every VAT receipt and I would think are likely to be extremely curious about a claim for a single end-of-project invoice, especially if they then identify that the supplier is a close company/controlled by you. Which seems like a very convoluted & risky way to go just for the sake of speeding up the cashflow of input tax recovery.

Indeed, the section of VAT Notice 708 linked above seems pretty clear that conversions are only zero-rated if done for a housing association. Fair enough. I would say that having several clients taking the same approach is not necessarily a useful guide unless one or more of them has had and survived an HMRC inspection. VAT is complex and not all accountants are on top of the details. I arrived in a past job to discover a VAT assessment of ~£50k for incorrectly claimed input tax plus interest & penalties. The accountants (who were otherwise pretty good) had signed off the treatment originally and had almost exhausted the appeal process on arguments they had put forward and lost. We had to appoint a specialist VAT lawyer/accountant firm who advised that the position the accountants had taken was hopeless both on statute and case law. Fortunately they were able to find an entirely separate basis to show we actually should have claimed the input tax and then charged an equivalent amount of output tax, which would have been fully reclaimable by our clients. So although the error was worse than thought, HMRC were not actually out of pocket overall. The Revenue's barrister eventually conceded that they were not guaranteed to win at Tribunal and advised them to rewind the appeal process a bit so they could cancel the case without losing face or establishing a precedent. It took about 18 months and still cost us five figures to defend, but a much smaller amount than revenue had wanted. We explored pursuing the original accountants for costs but quickly established that was a non-starter. Since then I have always taken advice about any detail of tax law/accounting with a large pinch of salt. Only mentioned stamp duty as you'd said earlier in the thread you were buying the finished property from the company. One other thought, it sounds like you're planning to live in one of the buildings - does your local authority have a Community Interest Levy and if so does your company structure get in the way of claiming a self-build exemption? We don't have CIL here but some of the figures I've seen on BuildHub over the years are pretty eye watering. Edit to add: of course I would also take VAT and tax advice from an internet forum with a pinch of salt 🤣 so if you're confident your accountant knows what they're doing then best of luck and as they say in Poland "not my circus, not my monkeys" 🙂

Indeed. More likely therefore that is a benefit : if the "discounted energy"/retail supplier lock-in model proved to be really not working for anyone you could in theory build a super-majority of shareholders to switch to a simple "charge the grid, pay us a dividend" approach. Likewise gives options if everyone wanted to sack Ripple as the managing agent and it became apparent that there was nobody else willing/able to run it on the Ripple model. Seems pretty unlikely it could be changed in a way that was detrimental to shareholders.

I looked at Ripple a bit a couple of years ago but ultimately decided financially for me at that point it made more sense to put money in traditional investments with dividend/savings returns. But from what I did find at the time: My understanding is Ripple are a service provider. They get the ball rolling on site finding/planning/etc then create a standalone company for each separate windfarm - constituted as a co-op - which is wholly owned by the people that invest. So the Ripple accounts show the money flows for their project management etc fees, the larger actual construction/maintenance costs etc are paid direct from WindFarmCo out of the funds raised from the investors. Ripple just organise the work and write the cheques on WindFarmCo's behalf. I don't think that's correct. They have created a company with shares which they are just doing the admin to transfer to investors as they buy in. The company presumably starts with some nominal value shares owned by Ripple so they can pass the initial resolutions to approve articles, appoint themselves as the first service provider etc, and then authorise a share issue for the actual investor shares. Essentially the financial/shares model is the same as if we all said "let's build a BuildHub windfarm together, but we don't know/want to know how to. So we'll get an off-the-shelf company from an online formation agent, set up a bank account and pay our cash in there in exchange for shares. Then we'll appoint a specialist contractor as the directors to run it all for us and review their performance/vote them out at an AGM.". The difference is just that Ripple are bringing together investors that don't know each other so they've done the first bits of admin to get the new co-op company going before the investors arrive. As above, ripple isn't a co-op, but the company investors are buying shares in is. The company is formed with an agreement to use Ripple as a service provider for X years, and then the investors can vote whether to keep them or appoint someone else (or presumably, appoint normal directors and hire their own staff to run the company, probably not cost effective but it's up to the shareholders). I suppose potentially the investors could also at some point vote to change the profit distribution mechanism e.g. to switch to traditional dividends instead of the discounted electric price model. It's probably written into the company's articles, but usually there's some mechanism for a super-majority of shareholders to change anything in the articles if they want to, unless co-op legislation is more restrictive than ltd co. I think regardless, you're probably not protected. If it goes bust, or can't deliver sufficient generation income, then you'll likely lose some/all of the benefits and capital. Equally if enough of the other shareholders vote to change e.g. the articles of association in a way that disadvantages you that could be a problem. On the other hand I think you're no more at risk than if you bought shares in any company - there's always a risk that mismanagement means a company doesn't deliver the expected profits, with the only safeguard being that if shareholders find out in time they can sack the management and appoint someone else in the hope they'd be cheaper/better. I think where that article says "With over 4600 reservations, Ripple said its biggest project to date is expected to sell out quickly" means that's the number of shares they've potentially so far, it reads to me like they expect to sell (an unspecified number) more than that? I also wonder if the discrepancy is just a peak demand / annual consumption thing. I think it's pretty common that when suppliers say "x turbine can power up to x households" they are talking wattage - 18.8MW would be about 940W per house on 20k houses if the turbines are generating at full pelt which might be reasonable as an average instantaneous household demand? Whereas the shares model is based on people buying up to 120% of their total annual electricity consumption. But obviously sometimes you will actually be using power from a solar/tidal/gas/nuclear generator, and other times you'll be sharing "your" wind turbine with folk that would otherwise be getting their power from other sources. So I think it's expected that the number of shareholders would be quite a bit lower than the maximum number of houses that could be powered at any given moment. Also in that article you linked there's mention of a £94k a year community benefit fund, which must be coming from generation revenue. So effectively some of the non-shareholder households that are buying power from the turbines are paying for that. FWIW I don't think it's a scam. When I looked, the articles of association for the WindFarmCo you'd be investing in and the operating agreement with Ripple were pretty visible on their website and fairly transparent about how it all worked. It seems to me it's as safe/risky as investing in any other newish business with co-investors who you don't know. As a model for funding wind construction, and having it owned by "ordinary" UK citizens rather than overseas finance firms, so the profits stay in our local economies, I think it's not an awful idea. But I do think potentially in trying to make something with mass market appeal (in order to generate investment from non-traditional investors) they have come up with quite a complex model. Personally I think there would probably be fewer variables (and probably less admin cost) if everyone pitched in to build the windfarm and got paid a dividend when it turned a profit. And if people chose to think of that as subsidising their electricity bills that's up to them. So for a serious/considered investment it would be worth looking at other options in wind (if environment is also a consideration) or basically anything if cash is the main motivator. But equally there's probably a fair few people that wouldn't necessarily think of using some of their savings to buy shares in a private company but would be up for "having a flutter" to get cheaper energy bills in future. And it's potentially reasonable from that perspective.

My past experience is event / festival sites where everything is run in a mix of 240v and 415v. The risk profile of an outdoor event site - especially during build and strike - is probably not that different to big construction. That said absolutely everything was on a commando plug until the very final socket (which was usually a single commando - 13a adaptor for a specific piece of kit). So imho 110v definitely has safety benefits but it is possible to make higher voltages work safely with sensible controls in place. If you have 240 on site for chargers then unless you police it there's a fair risk someone turns up with a 240v tool in their van and runs an extension lead(s) for it which IMO would be worse than having a safe 240 supply around the site.

I'm also very curious (sceptical) on the ltd company question. Do you have a fully worked model of all the costs and benefits of that approach? As far as I know if you're in control of the company it would need to be charging you on an "arms length" basis to avoid HMRC "looking through" transactions. For example, you can only be VAT registered for the purpose of "trade", if HMRC were to decide transactions were not for trade they could block any input tax recovery. I'd have thought by the time the company has paid taxes on a believable value of capital gains/profits, and you've paid stamp duty on buying the finished property out of the company (which you said earlier was your plan) again at a fair market value that's going to add up to a pretty hefty sum. The other worry would be that it is very common for self builds to go over budget, do you definitely have a mechanism to borrow a decent amount of additional finance if needed? I can imagine getting e.g. a mortgage would be challenging if the ownership structure is unusual. In my experience "cunning plans" have worked out to be profitable for the professional advisers that come up with and administer them and marginal at best for the clients. I have also seen cases where an inquiry into one client has led HMRC back to the adviser and then to their other historic clients, so the risk is higher than e.g. if you chose to interpret the rules "flexibly" off your own back. There is also a big difference between "unintentional" and "intentional/should have known better" penalty charges. My gut feel is that if this was a good way to make a big saving everyone would be doing it, and they are not. But please correct if we're wrong and missing a trick! On your actual question, I'd agree batteries for basically everything, 240v (off a proper supply with RCD protection) where necessary, make sure you are using IP rated sockets or preferably weatherproof CEE connectors ("commando plugs") in any area that is not fully watertight.

That's good you have confirmation of what the BCO will require. What I would say is that 0.30 might be compliant but is really a very poor u-value. Energy costs are likely to be high for a long time to come - if it was my house I would be looking at whether I could do better than that. You might end up with a slightly thicker wall, but you may find there's not a huge difference in cost to upgrade since you're doing all the work anyway, and that you would get payback pretty quickly especially at current energy prices. You really don't want to find yourself ripping it out to improve it if you find your house is hard to heat in a few years.

@ElliotP brilliant achievement! Would you be happy to share where you sourced the beads - were they just generic "packing" beads or something more specific?

I'm not sure what you mean by "that usual 1 inch of polystyrene stuck on the blocks", I've not often seen polystyrene used as internal wall insulation? Does the garage have a garage door - is that insulated and airtight? I suspect you will need to demonstrate that either the outer or dividing wall meets an appropriate u-value for the regs including any openings. Normally you ideally want the most water-vapour-permeable layers of a wall on the cold side, and the least permeable layers on the warm side. This reduces the risk of warm moist air from the room condensing into water as it cools on the way through the wall. So if you have wool between the studs you would put polystyrene/PIR on the room side, not the garage side as per your upload. However I would definitely check with the BCO about using polystyrene at all in a wall that requires a fire resistance. Usually I think you would need to use a combination of materials that has a manufacturer's test certificate to show it will stand up to a fire for the required time.

In Scotland, a wall is only "internal" if it is within the insulated envelope of the building. So if (as I assume) the unheated garage is also uninsulated then the wall between the room and the garage is "external" as far as u-values etc are concerned. If the garage is insulated (including the door) but just happens not to have a heater in it then there is no requirement to insulate the dividing wall. I assume the rules will be the same in England & Wales. In terms of improving insulation, options might include changing wool between studs to PIR (but that may be an issue for sound/fire), making the wall thicker to accommodate more wool, or lining the inside of the wall with a layer of PIR/insulated plasterboard over the studs.

Well I made three related points. First, that if at some point the oil price drops from current highs then the electricity price will also drop because at the moment the high electricity price is primarily driven by oil/gas. Second, that regardless of what the oil/gas price does there is an ongoing move to a) decouple the price of electricity so renewables generators are not paid a price based on the cost of the oil/gas they don't use, b) increase the proportion of renewables in generation. Third, that it's pretty likely that as that happens, things like "green levies" etc will gradually be shifted from electricity to fossil fuels - because it makes little sense to put "sin taxes" on the cleaner energy source. All those three factors mean that whatever electricity drops by it's virtually certain that will be more than any drop in the oil price. There is no realistic scenario I can see where oil goes down from current levels but electricity stays the same or goes up. As to whether it will actually drop an appreciable amount, I don't know. It may be it holds around the current level and the oil price goes up higher (especially as carbon taxes are ramped up). I hadn't realised that. All the same I think there's a strong chance that the relative prices for different energy sources will change significantly within the lifetime of the heating system. I suspect the way to go at very least is to invest in getting the insulation and airtightness as good as you can reasonably manage, and designing plumbing/radiators etc to be able to cope with a change of heat source in the future. Well yes, I said that you'd probably not be able to generate enough in winter. But if you can cover hot water year-round and contribute to the heating in the shoulder months that may offset slightly higher costs on the darkest coldest days. Probably depends partly on your actual heat demand - 1 person kicking around a giant house might be more of an issue than a big family taking long showers all year round.

All the signals are that oil and gas will become more expensive over time as carbon and consumption taxes move towards fossil fuels. Meanwhile electricity is expected to come down (or at least, go up less) both due to those taxes changing and also the increasing proportion of renewables generation. Bear in mind at the moment a big chunk of the electricity price is due to the oil and gas price so they will (in theory at least) fall together. The other factor is that you can self-generate electricity - perhaps not enough for winter, but enough to cover e.g. hot water outside the heating season - but you cannot produce your own oil.

Given the COP drops as temperature does (I think?) and at the moment it's a lot colder overnight, I'm curious about where the balance point for this is.

There was at least one of the companies I found, can't remember which - not groundscrewcentre - that did much longer screws, 1200mm or more, with the idea being you could have quite a long section above ground on a slope. That said levelling a bit might also be a good idea, especially if you plan to put doors on the long or downhill sides? I should also say that my "main" project at the moment is a 6 month extension to the house that is now in year 4. 🤣 Therefore part of the deal with my wife for the garden room was that we'd be happy to pay a little bit of a premium for solutions that "just work" so we can complete it and move on. So I didn't do a huge amount of research on more DIY options, I knew concrete was out so just went for ground screws. I can imagine there are ways to do it cheaper with probably not much more hassle but we valued the ability to get a single delivery one day and have the foundations done the next with no need to "pop back to Screwfix for something"!

I just hired the ratchet tool, so not a "machine" so much as a giant spanner You pay £180 (inc VAT) upfront, then you get £120 back if you return within 21 days - you have to courier it back though and it's heavy so probably works out about £80 to hire. It worked well, you do have to faff a little to make sure the screw is going vertical and it's pretty physical, towards the end of the drive I was having to use my full bodyweight to assist turning it. Though the bar is long enough you could do it with two people if you have someone else handy. Some suppliers rent fancy drills to power them in perfectly vertical but they are expensive. It's also extremely quick/easy to get everything level. Just run a laser line for the tops of the screws, turn the spanner until the line on the outside hits the laser, move on to the next. I got mine all within +/-1mm without any real hassle. I had 22 screws for a 5m x 4m base (could have been 20, but we have a dividing wall in the middle of the building so I chucked a couple of extras on that line just for the sake of it. Including the tool hire, the "Premium" joist brackets, and a chunky SDS drill bit for a pilot hole, it worked out about £47 a screw including VAT and delivery. The only difference I think between standard and Premium brackets is the standard ones are solid plate and you have to use 4 self-drilling screws to fix them together & to the top of the ground screw. The Premium are drilled with slots so you can loosely bolt together with the provided M12s then just tighten up once you have everything adjusted how you want it. It worked out about an extra £2 a screw, but I think that was worth it for the ease of fitting it all together. Probably works out more expensive than rubble/concrete pads, but super quick and in my case it's at the bottom of the garden and the only access is through the house so there was a big advantage in minimising the weight and "dirt factor" of the materials. One last thing, based on a tip on here I ripped up some thin perspex and put a thin piece on each screw between the metal bracket and the bottom of the timber, just to reduce exposure to condensation on the cold metal and hopefully keep the timber nice and dry.

I'm in the middle of a similar project just now, I used ground screws which has worked really well. No digging at all, just drill a hole then screw them in. And then built a 4x2 timber frame on top to sit the building on. You can get different lengths including ones that can have a section left above ground level, perfect for sloping sites. I got mine from the ground screw centre, and rented their ratchet installation tool - very happy with them!

If you have access to the ducting in the loft then you could fit an in-line backdraft shutter. They have a flap (either spring loaded or gravity operated) that opens when the fan is blowing air out but resists airflow in the other direction.

I felt given the time & detail you put into your answers and the food for thought I get reading them that you deserved a considered reply 🤣

I can't think of a 7671 reason that would prevent it. If there was then the large numbers of commercial buildings & hotels etc with lighting controlled by scene controllers/virtual switches/touchpads etc would be noncompliant. Or for that matter spaces where the lights are controlled entirely by e.g. motion detectors with no direct manual control. 7671 is concerned with two main things: * Isolation in emergency/for maintenance. Usually in domestic that would be by the circuit breaker at the consumer unit (strictly speaking you could argue there should be a mechanism to lock it off if the consumer unit is not in same room as the fitting, to avoid the risk of accidentally turning back on while someone is working on it - but in practice I think most people assume that the small number of people/communication in a house is likely to be adequate protection). BS7671 doesn't actually allow a normal lightswitch to be considered as an isolation or emergency switching device. And even if the switch type was approved, it is very common in UK domestic to have live conductors at the ceiling rose/fitting even when the light is switched off, so isolating the entire circuit at the consumer unit is the only real option. * Functional switching - the requirements here are much looser (basically just about what users need) and the regs specifically allow for controlling the current without having to actually connect/disconnect the circuit e.g. electronic controls. Functional switching is only required if there is a need to control part of a circuit independently of the rest of the installation. So from that perspective so long as you have some means to turn lights on and off in whatever combination suits you as the user, the electrical regs are satisfied. This is a very good point. Any system that isn't essentially failsafe - e.g. the lighting "just works" again after a powercut - may pose safety concerns that you would need to solve. To be honest, I am quite a fan of having standalone battery-backed emergency lighting in homes, I think the argument against requiring it is that occupants will be more familiar with the layout than in eg. a public space, but try to stumble out of bed and out of the house in the dark without tripping over something and you may think again, especially with kids! There are plenty of not-ugly options these days and/or smoke detectors with escape lights built in that I would consider. Very wise to consider that, or that you may have guests/a home exchange. And indeed that you may find your chosen manufacturer goes bust/drops support for all your kit/is inspired by car manufacturers to pivot to charging a monthly subscription to "enable" the kit you already own. So I would definitely be cautious with anything too "fancy", definitely not something that can only be controlled from a phone app or some proprietary home assistant type thing. But any of the kinetic energy based switch solutions are pretty foolproof I would say, certainly Quinetic stays configured after loss of power. So from a regs point of view they still provide the required functional switching and from a user point of view they are basically "fit and forget" - a guest / future owner might never even realise there's no wires behind the switch on the wall. Personally I would go with a kinetic energy switch with a relay/dimmer box & stick to a standard "dumb" lamp - I'm fairly suspicious of smart lamps as my experience (admittedly not recent) has tended to be that mixing electronics and lamps doesn't end well as they tend to overheat and die, and it anyway feels very wasteful (cash and environment) to shove more and more electronics into what will always be a consumable. Obviously it's fairly likely as an electronic component the switch will fail and have to be replaced sooner than an old-school switch. But IMO that's not that different to a dimmer switch - it's pretty common to have to replace them and people still seem to prefer them over a basic on/off.

As you say your spark will need to be comfortable but from my somewhat rusty memory of that aspect of the regs so long as the enclosure is properly rated (including sealed covers over the mcbs etc) there should be issue. If you ever look out the back of a tent at a festival/event/concert you will see an absolute forest of outdoor rated distribution boards, often on very substantial 3 phase circuits. They are usually one-piece rubber boxes with screw -tight lids. I think you would probably need a non-conductive unit as the earthing/bonding arrangements are usually different outdoors so a metal unit could be more complex in that regard depending on the details of location/circuit design/etc.

Ahhh - should have been more specific. What I have is 9mm utility board which I think is solid, my recollection is it was much tougher to cut than the fascias I had. I will double check when I dig it out tho. Failing that I'll find something more rigid - perspex maybe? I don't think the loading is huge, even with live loads & snow load included my rough calculation worked out less than 300kg per screw, so if I have my maths right over the joist bearing area it's something like 10 kg/cm2 / 140psi / 980 kPa.

Excellent point, thanks. I have some offcuts of uPVC fascia that would probably do the trick for packing the timber off the screw head. I guess I was just thinking with a french drain round the perimeter and then the only major source of water would be from the soil upward so a DPM would trap that below leaving the void above dry other than airborne moisture which should generally blow through the cross ventilation?

@Iceverge thanks very much. Do you think definitely a permeable weed membrane? I was planning that but now wondering if a DPM (as per the solum under a suspended timber floor) would make more sense. A drain round the outer edge is a good plan.

E.g. my plan as per this very rough sketch