Bitpipe

I have a plant room in basement, it sits under our utility and indeed is useful as it holds the gas boiler, MVHR and UVC plus incoming telecoms, power, PV isolators etc. It's about 3m x 1.5m so yours would have a lot of additional space for storage etc. The basement itself is full footprint with the rest being habitable space so meets full regs on means of egress etc. You may want to check with BC on exactly what regs you will need to meet. If you have a DHW tank that needs to meet G3, it will have to be able to vent externally so that may be a challenge. Be aware that the smaller a basement is, the more expensive it is to build per m2 due to plant mobilisation costs etc. You will need to tie it into the floor structure above to prevent it moving independently.

Another consideration is solar gain, the further recessed the window the more shading will be available.

We had a fixed price groundworks contract which mostly went well and the concrete team they outsourced to were extremely high quality, hard working and professional. But we did have problems, especially at the tail end of the project (basement backfill) and on the one week I was off site, many corners were cut that only came to light later - such as using un-compacted spoil vs the specified clean stone - always hard to say if it's just a lazy worker or a boss decision to save a few quid. I did not pay the residuals though so that was some recompense.

I did it as a DIY job as the ground worker was not experienced in using EPS so just left it to me. Only took a few days to do this (I also had lightwells to install from MEA). Only fiddly bit was cutting the EPS to have the correct height at the top to interface with the timber frame - annoyingly it need to be exactly 80mm higher than the concrete wall itself to match the Kore profile. I also used the EPS to form concrete corbels to support doors (sliding and fixed) that would not sit entirely on the basement wall but would straddle the insulated layer also. This was easy enough, the crew drilled and resin fixed stubs of rebar into the required area, braced with rebar at 90o and I chopped out a 100mm wide, 200mm deep channel on the EPS which they backfilled with concrete - worked great. SE obv signed off this design detail.

We bought privacy screens for the Heras site fencing which was a heavy duty woven material - very similar to your Amazon link but in pre cut sheets, seamed with eyelets etc. Anyway, even a breath of wind turned it into a sail and I was forever rescuing it from the road. Maybe you could cut some vents in it and patch over with squares of the same material, fastened at the corners, to reduce this effect?

If you are doing the supply then you need to buy the materials from a vat registered merchant with your name and address on the invoice. The trade can't buy the materials 'on your behalf'. I had a labour only deal with my landscaper and now and again I would to go to a merchants with him so that he could leverage his discount with the goods were on my account or some other fudge i.e. use his account but my details were on the invoice. Bottom line was that I had a clean invoice for the HMRC reclaim that was in my name and address and I had proof of purchase (CC receipt) - not that this is needed for the reclaim but useful to have.

Soudal LE foam, the type that needs a gun. Simply wet the EPS and the wall with hose and then do a nice big squirty pattern on the EPS and offer up to wall. May need to prop it until the foam goes off. You can then go round and foam up the joints. Always wear gloves as it sticks to your skin and is a bugger to get off. I then dressed the exterior of the EPS with 3mm corex, the stuff you use to protect floors when building. It's the same size as the EPS sheets. Just to give some protection during backfill. Tried stapling that but gave up and just pushed in old nails (had millions lying around from the formwork).

I think the consensus is that you will be marketing to a much narrower segment of the market but they may be prepared to pay a premium for such design. When it comes to 'green' features, I think they're better presented as generating a comfortable, consistent and efficient living space as opposed to virtue signalling. Our house is quite contemporary in appearance and is passive standard. However visitors comment that it's always a consistent comfortable temperature year round, the air is fresh, there is plenty of natural light and the energy costs are low (£2-3 per day over the year).

If you contact a seamless guttering supplier, they use a roll of powder coated aluminium and then run it through a former on site to create the guttering profile. If you use one for your guttering (and soffit / fascia) then they can easily do the plinth base also. @HerbJ did just this. Also consider Ubiflex (or equivalent) - lead flashing substitute. Apply it in a band around your base EPS and then put the bottom batten for the render system over the top.

25mm should be ok, how are you venting at the top? Ensure that the battens are fixed back to the structural members of the timber frame and not just pinned to the OSB. Your render company should have a detail that you can follow, even better is to get them to design the system and warranty it. Be very careful with your choice of renderboard - should be Knauf Aquapanel or similar.

We PMd our new build with zero prior experience. It was made easier by having two major contracts - one for groundworks inc. basement and one for the timber frame - between these two all the critical structural details were covered. The remainder was choosing and scheduling follow on trades & suppliers for windows, roofing, exterior cladding and then the first fix, boarding & plastering, joinery, decorating, tiling, second fix, kitchen etc. We sourced the 'visible' materials ourselves but deferred to the trades for their standard supply & fit items. If you're hiring a single builder to execute the project and they will in turn be providing subs etc then the majority of work will likely be taken care of and you'll be ensuring what's being built is as specified and be on hand to make quick decisions when there is ambiguity.

Your choice obviously, although £8k sounds very expensive for MVHR. The entire system for my 400m2 cost £4k. In my opinion, MVHR's primary function is to deliver continuous controlled ventilation to every room, the heat recovery capability means it does so efficiently. In an airtight house it is essential but as yours is a conversion, you may not reach the airtightness levels to really take advantage of the efficiency anyway. In a sufficiently airtight house you can leave the front door open and there will be no draught in or out as there is nowhere for the air to go.

Guy who did our landscaping has branched into mini digger hire. Leased 5 new machines a year ago with his business partner and kept one in a container 'box fresh' while hiring the other 4 out as his contingency. He says it's shot up in value and he is sorely tempted to sell.

I was browsing B&Q today on the off chance and found 5 bags of ready mix in the next town so bought them. Order cancelled 5 mins later when they tried to pick it. So re-ordered but 4 bags. Same. Went to re-order for 3 but they've finally updated stock to show just 1 bag left which is not worth the journey. Still, kept me entertained for 20 mins...

The COP of MVHR did not bother me that much as, given my house was designed and built with very high airtightness, I *needed* an efficient all room ventilation system so that was my primary concern and the efficiency of the heat recovery was important but secondary. That said, I found this https://www.paulheatrecovery.co.uk/products/methods-of-calculating-the-heat-recovery-efficiency/ so maybe somewhere to start.

I see your challenge. Given your constraints I don't think you have many other options. If you were to forgo the kitchen extract you'd need to double up the ducting for the utility to make the system easier to balance.

One you can get on loan from the forum for £10 Plus £780 for a design you'll get other places for free. £1400 is almost half of what I spent on my whole MVHR system.

I used BPC, design was free and they use the Vent Axia Sentinel Kinetic range. Just take layout designs as a guide rather than gospel. You may well find that you need to adapt it to site conditions so having some buffer in ducting materials is a good idea. Depending where you are with your drawings, the MVHR design is a good indicator of where you may need steel or other structural penetrations. I missed this detail but was lucky to find a few alternative routes, bypassing tricky steel work (ditto for plumbing).

The recent covid recovery stimulus passed by USA govt may also stoke inflation and if they pass their much needed trillion dollar infrastructure bill then demand will go through roof, and inflation with it. My wife works in the semiconductor industry and they are experiencing severe production shortages with lead times slipping out to 52 weeks in some cases. Why? Fabrication (the expensive bit) has been progressively concentrated to a few locations and just one interruption causes massive impact on supply.

Condensate forms inside the unit and flows to an output pipe which is connected to waste water system.

Stash it next to the loo roll and pasta.

Or cement based products (although that's more availability than price).

In our case, after discharging all pre-conditions (no CIL for us), we needed to do some drainage works to facilitate moving into caravan and allow demolition. We had the independent BC onboard at that point and he actually encouraged us to make a start to lock in compliance against the current regs which were about to roll to the newer version. So laying some duct to the sewer ticked the box and we did nothing else for six months.

Popped out for some postcrete for a DIY project - none in town (sheds or BMs) - managed to get last 3 bags in next town along at Screwfix. No cement based products of any description available at moment whether bags of dust or the DIY readymix bags.

No as MVHR is continually running as its the sole means of ventilation, there is summer bypass where you can avoid the heat exchanger. The principal of airtightness is to control the egress of air that you've paid to heat vs having it blow uncontrolled out of the house. For me, the heat recovery element of MVHR is secondary to its primary function of effectively ventilating the whole house. As with others, I leave doors and windows open in summer but I can be more efficient in cooler weather and reduce my heating costs.