Bitpipe

The EU deal is tariff and quota free but all the other friction that's part and parcel of being outside the Customs Union and SM such as conformity and origin etc. now applies. We're also outside the VAT collection scheme so traders need to do this individually with HMRC. The UK is not currently enforcing its import checks (June?) so we're only seeing half the issue at present. Yes, some of this will settle down but some will be a permanent fixture as a result of being a 'third country'. As I read somewhere recently - UK developed the single market UK developed the 'third country' rules UK enforced the 'third country' rules UK decided to be a 'third country'....

Well, they may or may not be, but worth checking. If you PM me I'll send you the details of the buyer I used to source my EPS - always good to have in your back pocket as unlikely it will be a bread and butter item for a ground worker - also ensures you get the spec and not just any old EPS.

Whats your plan for that corner section? If the crew are doing traditional shuttering then can you just lay the 300 flat and butt the 100 vertically on the edge? Also are 200mm sheets cheaper / more expensive than two 100mm sheets?

Ok but my advice is to watch their work closely as it's not typical and it's your insulated envelope, not theirs. Don't let them bodge it. I purchased, supplied and laid my own EPS as the GW was not familiar with it. Check with your TF company where the EPS needs to finish, for MBC it needed to extend past the walls by 80mm to match their Kore slab system.

Yes, VAT applicable to disconnections, alterations and service moves. If you can, just move it once from the house to a kiosk that will initially give you site temps but can also be your final supply - you just run the house supply back to the kiosk and need never bother the DNO again or pay their fees.

Totally agree - things that drive you mental now, you will struggle to notice when it's done.

Ok, get out your pen and paper and figure out the best way to lay the 1200x2400 blocks to give you the necessary footprint, plus a bit of excess 'toe' under the slab to sit your vertical panels on. If you have a chainsaw that has a bar long enough to cut through the slabs then use that if required.

It depends on panel & inverter cost (In roof systems can mitigate some of the cost by removing the need for other roof coverings in those areas) but if you think year round it may make more sense. If you're building to a reasonably high standard then you will find summer overheating as much of a challenge as winter cold. In fact, overheating can be an issue in spring and autumn when the sun is low and comes straight through windows. An electric based comfort cooling system (split air con or if you have UFH and ASHP, cooling the slab) will effectively be free when the need it at its highest. We have a solar PV diverter which heats the UVC through immersions when energy is not otherwise being used and that has paid for itself very quickly. Timing laundry and dishwashing to the day time (easy with modern appliances) also means they run for free. If you have or are considering an EV then you can charge that at home during the day for free also.

As long as it's just bearing a flat load and is not expected to contain concrete then you are fine. Get your SE to spec the lowest strength EPS you need for the slab based on N/M2. EPS200 was good enough for us - it gets progressively more expensive for 250 and 300 grade. If you can, avoid cutting the slab EPS it as it is very dense - a hot wire or small chainsaw are effective means - the latter does generate a lot of EPS chaff! Walls don't need to be more than EPS 70 but again get the SE to confirm. Easy to fix these to smooth concrete, simply wet both surfaces with a hose and apply a generous bead of Soudal LE foam (with a gun) and slap them together. You may need to prop the vertical slabs until they adhere, takes 15 mins or so. Then squirt any gaps between sheets. Our SE advised putting sheets of 2-3mm corex over the EPS to protect when back filling. It's very cheap. I tried stapling it but reverted to using old nails salvaged on site to peg it in place!

The heat loss only tells you your space heating requirement - from memory you plug in your desired year round inside temp (say 20o) and you'll get a w/m2 value. This is what your heating system needs to inject to get the required temp on the coldest day of the year so helps you size the system. If the house is well insulated and airtight, MVHR etc then you'll probably be looking at a low temp UFH system with additional underfloor (electric or wet) in tiled bathrooms for comfort plus towel rads. If your house is going to perform very well, you likely don't need heating in bedrooms as convection will circulate heat in the house - note MVHR does not significantly move heat around, it is intended to ventilate and minimise heat loss while doing so. Domestic hot water (DHW) is a function of how many people in the house, how many concurrent baths and showers there are likely to be etc - more a consideration of storage (UVC vs Thermal store, and litres stored) plus acceptable recharge time, cost to run etc. If you are on mains gas and want to continue with that, you'll have a nice efficient boiler (e.g. greenstar) which will deliver hot water for DHW and then mix it down for the UFH. If you're all electric then you may use an ASHP and follow the same plan or target it at the UFH temp and consider a means to boost for DHW - Jeremy used inline electric impulse heaters. Others have used Willis heaters etc for their hot water generation and timed with PV generation or E7 etc. Plenty of more knowledgable people will now come along and polish what I've said

Given we were using traditional timber and steel shuttering for the concrete works, we just used plain EPS 200 forms (300mmx1200mmx2400mm) for the slab and laid them on a 50mm blinded sand layer over 150mm compacted crush in a simple flat layer that covered the slab footprint with a 3-400mm overlap all round. I though they may need pinned but they are so heavy they stayed where they were placed. The EPS slab was covered in membrane and the ground workers built their slab upon it as they normally would. When the vertical walls were cast, I simply glued (using LE foam) sheets of 200mm thick EPS 70 to their external face, sitting them on the EPS 300 that projected from under the slab. This completed the EPS envelope that rose to meet the MBC frame. MBC provided a steel and timber web as the ground floor into which we laid UFH spreader plates & pipes and decked over with 22mm OSB. The build progressed as usual from there. My understanding is that Kore and the like are used when the EPS is the shuttering for the concrete.

Many here have done it and can provide advice. @jack @HerbJ to name two!

No, you should still be able to install the windows once the frame has been erected but you will probably want to frame out the internal reveals if your windows are straddling the insulated layer. I recommend Compriband between the window and frame for a good seal (not foam) and when your VCL is installed you can use airtightness tape on the internal perimeter of the windows back to that. The MBC approach is to erect the structural frame and then board out the interior face to create the insulation cavity and allow windows etc to be fitted. They then cut holes in the internal OSB and pump the insulation in before sealing and completing the airtightness detail. On my build they used a new internal board that also provided the airtighness layer, at @HerbJ they applied this layer over the OSB. The service void is created by facing the insulated layer with 50mm battens onto which the plasterboard is applied. This means that sockets boxes, cable runs and the like are fixed to the battens and never penetrate the airtightness layer. If you want a penetration from inside to outside, it's easy to do but you use conduit (drilled and placed at a downward angle to stop rain ingress) and tape up where it exits the VCL. When the cable or service is run, you can seal the interior with silicone etc. It's all about detailing!

+1 to the advice above. We were novice builders and having one company erect the frame and get it watertight & airtight plus all internal stud walls, floor decks and temp stairs, plus roof felted and battened meant we were able to tightly schedule windows, doors, roofing and cladding within a few weeks and could go straight to first fix. If time=money for you then it's a good approach. Just be prepared to normalise a lot of your quotes as many vendors include / exclude different items - some material and some operational (like crane hire) so it can take a bit of work to get an apples to apple comparison.

We have engineered wood in all the upstairs and it's rock solid. Decent quality obviously.

That is the best way forward - kind of thing you can do yourself - start with a 1m2 excavation from the meter and you should not need to go super deep. https://www.hse.gov.uk/pipelines/faqs.htm#:~:text=A gas main should normally,mm in footpaths and highways. Once you find it you just follow it along until you get to the road or the point where you will pivot to another supply trench. Out of curiosity, what's the plan once you've exposed the existing pipe? Have Cadent Gas agreed to the plan and come back with a list of contestable and non contestable works? - Contestable means they're ok if you do it (e.g. digging a new trench) whereas non contestable means they will do it at their cost and charge you whatever they like!

If you're not having gas at the new build, where (& why) are you moving the meter to? From my experience, when you are demolishing you need to get National Grid to decommission your meter and have your billing company collect it to close the account. You are not allowed to mess with their supply to your meter, even if its on your land. Ok, I didn't see your answer above. If your supply pipes is metal then a CAT detector may find it. If it's plastic (mine was) the only way to find it with a Cat detector is to insert a sonde in the pipe which the detector picks up. But obviously this means removing the meter and putting the probe in their pipe which is a no-no, but is how national grid determined where to dig up the road at mine. Mains gas is actually relatively low pressure so they put a blob of black gunk at the meter end of the supply pipe until they located it in the street and properly capped it off there. You probably need to carefully dig a trench by hand near where the pipe exits the meter / house until you find it and then try and determine where it goes. I did this with my electricity supply (the CAT scanner was not terribly useful) and dug the jointing pit and trench to the new meter location which was in a kiosk). Question is whether they will agree to make a new joint on the original pipe to the new location (no idea), whether the existing pipe can be lifted and relaid in a new trench to the new location (assumes it's long enough) or whether they will want to run a new pipe from the street main to the house. You'll need to provide the yellow perforated trunking for new pipe runs as they don't bury them unprotected anymore. Gas supply pipe is not that flexible so you need a pretty much straight run and any bends will need a very generous radius.

How big is big? I had a 20m x 6m lawn at the front of the house that was the last to get done. Had used turf everywhere else and that acts as its own kind of weed suppressant. This patch was mega weedy, I used a bog standard spray from a shed and it worked well - although only really effective in the growing season when the plants are active and will want to absorb the weedkiller. I also dug out any stubborn weeds by hand and raked and levelled the soil. It was December at this point but I sowed the seed anyway and it germinated fine. By May the lawn had established enough that it weathered the summer dry spell just fine - I'd had other areas that were seeded in April initially flourish and then wither at the first blast of summer (we're in SE so I suppose depends where you are). We now have a lush lawn, much better quality than the turf elsewhere. Still needs a regular manual weed but the grass growth does act as a natural inhibitor. So, I'd get out there now weed and then sow once this cold snap has passed. Grass seed is not that expensive so worst case you do it again if it doesn't germinate.

I think you're on to something, I can think of a few other threads that could pull in the money - although @Onoff 's bathroom thread would be like Corrie or the Archers (40 years & counting...)

More anecdotal than evidential but a fair chunk of our build (frame, basement elements, bathroom fittings, internal doors, velux windows, stairs, furniture) was euro priced. We built from summer 2015 to summer 2016 so benefited from the 1.4 exchange rate pretty much to the end before it dropped post referendum. Looking at the historical exchange it looks like we were lucky in that respect. I've had a few trades back over the last years and their day rate has not changed appreciably.

Can't wait to see the delivery charges for that

We have a bog standard Harvey Dual Flow unit supplied and installed by the plumber, takes the pellet salt which is widely available and inexpensive (I get a bulk delivery of 20 x 25kg bags every 18 months or so). It's wholly automated, does not need any power supply. It's a bit messier to refill than the block salt alternatives and it's run out a few times without me noticing so I now tend to top up weekly on bin night just to make it a regular habit. I recall that block salt was in short supply last year so maybe that's a consideration.

You can't do that as the panels need to be in the trays to make your roof watertight. Theres another active thread with pricing for trays & panels, look at that for some lower pricing suggestions.

Usually a sliding door to let the dog out. But we got a lab so I'm banking on it's heat output offsetting the heat loss.

Have you ever lived in a passive house? That statement is clearly silly. Our passive standard house (not certified but met all of the requirements) was not noticeably more expensive to build than a 'just passes BR' equivalent. The frame cost, which provided the majority of the passive compliance/performance, was about 20-25% of the overall build budget and included all internal walls and floors also. We opted for triple glazing which was not that much more expensive that double. Majority of our costs were aesthetic and lifestyle driven. MVHR was a few thousand and we saved on installing any heating beyond the ground floor and bathrooms so that pretty much cancels out. We open windows and doors a lot, whenever we feel like it. I pay about £1/day for gas and £1.50 for electric over the year in a 400m2 house occupied by a family of 4. What is harder to monetise is living in a house that sits at a constant 20o year round, low humidity and continually refreshed air.