Bitpipe

You also need to allow for non build elements such as planning & building regs (you'll need drawings, etc), SE fees, site insurance and a warranty should you need a mortgage on the property post build or wish to sell within 10 years. I've not done the final sums (still spending ) but we're probably between £1500 and £1750/m2, excluding land costs. That's in the SE - I hear build costs of £2-2.5k/m2 are not unusual now.

Welcome, you have two similar threads running so will probably get doubled up comments Always consider the option of buying a tired property and demolishing. Advantage is that services and access are already in situ, plus you can usually replace whats there with something 50% bigger and potentially more, still VAT free. Downside is that you're knocking down something you've paid for, and there may be more planning pressure to 'fit in' with the local vernacular. However given how long it takes to get planning etc, you can live in the property during that phase and save money. Also considering living on site during the build to save even more.

Due to the low airflow rates (even in purge mode) and low heat carrying capacity of air, MVHR has pretty limited ability to change the temp of the internal air, its best viewed as fine tuning. For me, MVHR's main job is to deliver fresh air and extract stale/humid air while not allowing excess heat to escape in winter and (hopefully) avoiding unwanted heat being introduced in summer - although without any active cooling, not sure how effective summer bypass really is (as it's just turning off the heat exchanger when outside air is cooler than internal in summer). We have a couple of large velux in the roof over an atrium and these get opened regularly in the evening once the outdoor temp has dropped and this is proving very effective at cooling the house. Windows and doors are kept closed daytime to prevent warm air getting in, blinds are also adjusted to minimise solar gain to east and south.

Agree with much of what has already been said - passive houses are much more sensitive to the site orientation due to the need to control solar gain - overheating is a major risk with large expanses of glass in a highly insulated airtight envelope. E.g. we invested in integrated electric blinds for all front east wall windows and all south and east roof windows. Probably need to build a bris soleil or pergola to give us more shading at the rear which faces west. I have friends who built (with an architect) a beautiful contemporary home with big windows onto amazing views - now spending additional £££ on light reflecting solar film as said windows are causing massive glare and overheating. There's also no real reason why a passive house should cost that much more than one that just complies with regs, the most important 'passive' aspects are in the initial design (PHPP is recommended to estimate performance) and achieving the required insulation and airtightness - the later is more of an on-site attention to detail issue vs big expense in materials. Many here have used a certain timber frame firm to deliver a passive frame and foundation system that is guaranteed to meet the passive standards - this removes a lot of the complexity in ensuring the design and on site detailing are correct but again, no reason traditional build methods could not achieve the same performance, however you'll need to take much more control of these aspects. MVHR is usually a £2-3k investment - you should think on where ducting needs to go and make design provision (vaulted ceilings can be a challenge) - this would appear to be the most common 'gotcha' that many builders on this site face High performance windows can also be had at a reasonable cost (note though that bifold doors are not usually that airtight, sliders perform much better.) You'll likely save some on having a simpler heating system without the need for rads in every room etc. If you're on mains gas than a traditional system boiler is usually the cheapest and most flexible option - many here use ASHP and electric for DHW, solar PV may be a consideration depending on roof orientation. Forget any kind of woodburner in a passive house, you'll overheat. Practically everything else will be the usual aesthetic vs quality vs cost choice (kitchen, bathrooms, flooring, doors etc, etc..) and this is where the majority of the cost is. £1300 / m2 is potentially achievable but will require a lot of work on your behalf, especially as many material costs have increased by around 20% since the pound dropped in value post Brexit. That said, well done for putting some deep thought into this already. What you end up with may well bear no resemblance to what you've designed but at least you're thinking it through and seeing some of the compromised that need to be made. The fact that you've done similar before will help.

We have similar beams in a few rooms and have LED strips on a 45o angle that work really well.

Each of our 4 bedrooms has a 3m run of Ikea wardrobes (two doubles, two singles) plus another 5 units in the dressing room. We put the fancy lacquered doors on our ones and the guest room and for the kids put the more basic doors on and applied full size vinyl murals from Wall Sauce. Joiner framed them into the wall with MDF so they look built in. Look good and cost wise, they're pretty unbeatable when you allow for all the internal fittings. By the end I could get one finished in just over 20 mins, however it is very easy to get the fixings / holes mixed up if you lose concentration. Never want to see one again though. I did made the kids assemble one each as a 'life skill'

Cheers, never heard of them but will give a shout on Monday!

Thanks all, will hold fire then. Wife acquired a bunch ex-farm chickens last week so i've a new chicken coup and run to assemble this weekend, will keep me busy...

I suggested a plunge pool but was over ruled.

I have a lovely storage container (25ft) with a fully finished site office on one side and 15ft of insulated storage on t'other. Can also be used for hosting international parties, provided you take the boxes out first (site office doubles as handy DJ booth / cloakroom / ticket office).

I believe you can stack two vertically and have pallet line treat as a single pallet (I see a few eBay vendors do this). I'd be happy to clean out IBCs used for whisky production, might take a while, wouldn't want to waste any....

Sounds like the self cleaning coffee machine I bought. Makes great coffee but I still have to dismantle it every week for a thorough clean...

Vendor emailed to see if I was happy with the ones on a wooden pallet vs metal or plastic, I said no so he's cancelled my order as the've run out of the non wooden type. Back to the search then!

Will she need to access it during the build? I can't imagine that a full length zippable bag / suit carrier style protector would be that expensive? Otherwise box it up and store with a relative. Or post down to me and I'll put it in our Indiana Jone esqe box room in the basement (supposed to be a gym at some point in the distant future).

Thanks, completely by accident too as the inclusion of electric UFH was a last minute (i.e. we had already tacked pb everywhere) decision but that generated the increased levels. Our floor guy did need to make a small ramp of latex outside the bathroom so that the oak floor in the hall was flush with the tile, it's very subtle and you'd never notice. I'll take it as a win.

So just bought 4 clean IBCs for £18 each on eBay, delivery was expensive though but it still worked out cheaper than the specialist sites. Now off acquiring all the other bits and will update on progress!

I bought a gun from Screwfix and it's lasted over two years and about twenty cans of foam (used a lot when applying EPS to walls of basement). Have never cleaned it, just keep it screwed tight and attached to a can - even after 6 months it works fine when you knock the dried tip off! I found www.abbuildingproducts.co.uk to be pretty decent for buying bulk Soudal LE, they're also happy to deliver.

This is the one we used - Lusso Stone 25mm, 1700x800 I think but they do then in all different dimensions. https://www.lussostone.com/showers-c6/shower-trays-c13/modern-low-profile-polished-stone-resin-rectangle-shower-tray-all-sizes-p851 We created a walk in style shower with glass along the long edge and entry on the narrow side. I sealed the shower screen glass direct to the tray itself, to do this we cut the side alu profile 2mm proud and sat the glass on spacers when fitting, sealed up to each spacer and when the SikaFlex had gone off, removed the spacers and filled the gaps. Used Nick's bombproof instructions for seating the shower tray also. Used an 8mm alu profile on the vertical side sikaflexed to the wall and a steel bar to opposite wall for stability and then just grouted the tiles as normal - its not a wet room but looks like one.

Ian, that's pretty much what we have in our bathrooms, 6mm cheap tile backer board (which is insulated). We got the mats from ebay, (lowest w/m2 we could find) latex and then and tiled on top - was pretty much 25mm from subfloor to top - I know this as the tiles are flush with the 25mm shower tray in one room. Have you looked at microscreed? gives the polished concrete floor look but is only 2-3mm thick.

How on earth did you survive all those chain smoking, farting builders

Our guys poured 2.8m high walls (300mm thick, 6m lengths) for the basement and used the poker all the way down as soon as the concrete was in the formwork, they also ran the poker over the surface of the formwork on both sides. When it was struck it was perfectly smooth with no honeycombing at all. Pretty essential for waterproof concrete I understand to ensure the aggregate is properly mixed and there are no air pockets. We also had window apertures cast (essentially 'holes' in the formwork) and they worked to get the poker underneath these to make sure the concrete was filling them properly, again no issues. For me, this is one of the drawbacks of ICF, you can't see the quality of the resulting pour.

I don't seem to get that smell so much ( I know the one you're taking about) - I try to give it a good clean before hand and mop up any wet or loose material. Also got a spray from Neff that's used on cold ovens, supposed to be as effective as the burn. Not used it yet - could well smell just as bad!

I've done the pyrolytic 'burn' on ours a few times - does get mighty hot but I just open a window. Usually do it on a sunny morning so the electric is free via PV

We got baths, washbasins and a shower tray from Lusso, really impressed with their post sales customer service too.