TerryE

@embra, sorry for the delayed response. If you look at the top pic, you can see how we handled the door thresholds. We cut a 50 mm slot at the top of the EPC insulation / formwork and then added an extender to the planned depth of the span. The guys added rebar in this and tied it to the ring-beam rebar so that the slab pour also flowed into these cut-outs, leaving a cast 50mm deep reinforced "ledge" to carry the door. Well, "carry" is really the wrong word as the Internorm frames were also supported on the sides and top in the same way as the windows, so the door base carries minimal load. You will also see that these door cills were also slated externally to finish off; under the slate, we had a 50mm upright EPC at the edge of the cill to act as a thermal break between the warm slab and the external skin. OK, there is a small thermal path between the cill and the slate, but even in the depths of winter we don't notice any significant temperature drop inside the doors. I did do a spot-thermostat survey the winter after we moved in, and the floor immediately by the doors got down to around 15°C -- enough to notice on bare feet, but well above any condensation threshold.

Not much to be done about that apart from shopping around online. We got a far better price than my builder got with his full discount from TP.

The socks worked well for us, but we had a TF inner. I'll defer to @nod on this one since he's the one with brickie expertise. Even so it all depends on how particular your brickies are. Some are very clean and hardly drop any snots into the gap, and some couldn't give a toss. In this last case, snot build up above the DPC can be a real problem and cause a dampness bridge if not properly mitigated, IMO. In our case we lived adjacent to the build site so we could clear out the socks and reposition them each night after the workmen left for the day. This meant it was zero hassle for them. You just need to agree a workable approach with the tradesmen onsite and check that they are following it. Are you filling the 200 void with insulation? Maybe using some runs of ABS or metal gutter resting on the tie rows might work just drill a hole in one or both ends and tie a cord to it so you can pull it out if it does fall.

IMO, this whole issue of where to place Air Tightness Layer (ATL) and Vapour Barriers (VB) is not settled in terms of proper scientific investigation informing building advice and guidelines, so at the moment there is no right answer. Note ATLs and VBs are not quite the same in that a VB is breathable but generally moisture resistant. As I said in an earlier post, our MBC house adopts the approach of having a minimally breached ATL as a racking plasticised OSB layer on the inside, allowing to frame and insulation to breath outwards. @ggc's seems to flip this. As I said , this isn't settled so we can't say one is right and the other wrong. As I see it, the MBC approach has the advantage that the temperature gradient from inside to out goes uniformly from house to ambient temperature to the relative humidity gradient goes from low to high helping to keep moisture out of the frame itself. But I might be wrong here. However I can make some observations. If you want an airtight (+MVHR) build then you need to have a robust and simple strategy / design for ensuring airtightness from design through to build completion. Tradesmen will not understand this and can easily compromise it. So you need a simple rule to enforce. In our case there is a 45mm service void in front of the ATL, so all wiring, cabling, plumbing, etc. was run in this void; flush to plasterboard pattresses sat in the void, and we personally fitted any through viod ducting. Tradesmen were not allowed to break it. If you don't do something like this, then your as-built house will end up leaking like a sieve. Any twin wall void needs to be breathable on one side. Double ATLs are an absolute no-no, because if there is any water ingress then it has nowhere to go; it can't dry out and rot will set in. Someone on the build must fully understand this strategy and police it. This could be you, a PM or an architect, but this needs to be done preferably on a daily basis, because even with the best intentions some tradesman will make mistakes, and these need to be picked up and remedied before the mistake is hidden and buried. All of the above also applies to the thermal insulation design, thermal bridge prevention, etc. Same arguments apply: Maybe trust, but always verify.

The alternative is to counter-batten the 50×50s. Somewhat like this Swedish guy does here on YouTube, but this does mean that you need to lay your PB in landscape mode. At least this way the studs are supported on 600mm centres. I like this continental idea of running all cabling in ducting, though note that they use multicore, rather than the UK practice of single core.

IMO, one the best things that we did was to provide regular Tea and biscuits, plus morning bacon sandwiches. IMO, tradesmen are good people in general, but with natural biases: they will tend to try to do a better job if they like you and feel that you respect them and their work. And yes, Ian has a point. Many aren't too tidy, but keeping the site ship-shape and making sure that nothing that you are directly or indirectly responsible for impedes their work can help.

I broadly agree with Mark except with one caveat: for some things, you really do need to do what you are doing because lack of knowledge and experience can endanger your home and it's occupants. For example, I wouldn't plumb an Unvented Cylinder because doing this is yourself is against BRegs, and because getting this wrong can be dangerous. I did rewire my last house, but that was before current regulatory requirements and the IEE wiring regs were at Rev 15 and it's now at Rev 18! You really need a qualified electrician to certify all mains wiring and register the certificate for your BInsp to sign off the work. Some electrician might be willing to allow you so do some first fix, but we just subcontracted a decent electrician to do ours. To be honest doing all woodworking, the plumbing, MVHR, all bathroom and kitchen fitting, project management, procurement, house and CH control, etc. was enough for us.

Direct ammonia fuel cells are still very much a developing technology, but even with these the end to end efficiency v.v. BEVs means that the price / kWh is almost double so IMO they will remain a niche use, e.g. for shipping and aviation.

One last codicil. It's worth covering the soil under the deck with a decent build fabric and a thin layer of gravel to keep it down, once the posts are in place; otherwise you might get problems with weeds, etc.

We built our own. There's probably some pics on my blog. We use some spare roof joists for the stringers I just cut a load of rhombus shaped bits of ?15 mm? OSB that acted at tread spacers: put in the next tread, then left and right spacers directly sitting on top with a couple of screws to fix them and repeat until we reach the top. I used 22mm chipboard flooring for the treads but each had a 40 × 60 (IIRC) bracer glued and screwed to the underside. This bracer was 2×15 shorter than the tread so it would butt against the spacer. The treads were directly fixed, but instead I put 2 × 100mm self tapping fixing screwed in from the outside through the stringer and into the center of the bracer. Two staircases because we have 3 stories, with the ground floor one using a platform to do a 90° turn halfway up. They were solid as rock, and did the job well. I precut all of the bits on my table saw so these were pre-toleranced to better than ½ mm. When I say "I" above, I really mean "we" as we swapped roles for the top set and Jan did the erection / assembly whilst I did the fetching and carrying.

The top soil / made up ground will have inconsistent ground bearing pressures across the footprint of the deck. Hence if you use pads that aren't footed on the virgin clay, then you should expect some degree of differential settlement across the pads, and some buckling of the deck in consequence. Pavers are a bad idea for pads unless you correctly load spread and the posts will tend to break them up and punch through them. The method shown in that Wickes video is about the simplest. The holes really just need to go down to the virgin clay, which might only be 30cm or so, but you won't know until you've dug a few out.

We've got an MBC TF with natural stone outer leaf. We didn't use SureCav as discussed in the following topic, but in our case we had a twinwall TF inner that was structural with the insulation internal to it. With your block inner and insulation in the void, this might not work for you. Even so I think that the suggested EPC option is a lot simpler, though I would be loath to drop the ties. The idea of bulging walls in a decade or so is horrifying. You can get long ties to span the gap and these wouldn't be a problem for the EPC fill.

The nice thing about the rivet-like anchors is that the piston gives you enough purchase that the outer flange gets buried slightly so it ends up pretty flush to the plaster. Very discrete. After touching up with paint, even with the hanging removed you can still only see a small hole.

@Temp that one is more understandable as this is big data integration internal to UncleG. All I can assume is that G monitors any pages that reference YouTube, such as @Dreadnaught's above link and it has somehow previously managed to associate my TerryE ID here with my gmail ID. Oh Big Brother where art thou?

I've got to wonder how Uncle Google is listening in. I've just gone to YouTube and for the first time in months I've had something like: YouTube -- Fixing Big Holes from Drywall Anchors! recommended to me. 🤣

The issue with quite a lot of fixings is that they don't service the fixing being temporarily removed because the back bit drops down down the cavity. A total PITA IMO. I find those squeeze-grip fixings very effective but you need to work out how to remove them with the minimum amount of damage if you need to. In the case of these fixings, I find that the easiect way is to unscrew then part rescrew in the bolt then give it a bang with a hammer. This punches the whole fixing through into the void -- at least enough to leave a small indent or even a small whole which can be filled, sanded down and painted. What ever you do, don't try to pull them out as this will tear out a big whole in the board.

A door is ~ 2m2 in area and you only have a few of them, so a U-value of 0.65 vs 1.0 or whatever is small beer in terms of the contribution to total heat loss. What is more important IMO is how airtight it is. If it doesn't seal properly then you will lose far more heat through draft cold air exchange, especially if you are using MVHR.

@Petrochemicals Any member's reputation gets a bump when another member gives them an upvote like or thank-you for a contribution, and this enhances their reputation. It takes a lot of effort / contribution helping other members to get a reputation over 1K, let alone one of almost 4½K as in the case of Nick . The reason that "Anyone would think I'd touched a nerve" is very simple: you have done so by the tone and content of your replies. Perhaps you shouldn't disrespect people when you are seeking free advice from them. I suggest that the wise thing for you to do here is a reboot: try seeking help on another forum. This is my last comment on any of your topics.

I browsed the topic and on reading @Nickfromwales first post, my honest reaction was that they were reasonable scoping Qs aimed at focusing the discussion into something valuable for you. You have now twice replied by trolling in response to reasonable points. Not a good start for a new member.

What is the domestic gas boiler penetration? I would guess of the order of 60%. ASHPs about 1%. If the government is serious about its energy targets then this ratio needs to collapse.

I agree with your basic analysis and that we need to be fairly clear about RoI decisions which should inform such decisions. In some cases equipping a new build was easier because man choices had to be evaluated and executed in line with the overall build program plan. The options where realistically yes or no; there wasn't a sensible defer option. Examples here for us include the decision to a warm loft to create a 2½ storey layout; the adoption of MVHR, the use of SunAmps for DHW. In the case of ASHP, I deferred to decision to install the ASHP itself, but instead I put in the Willis heater as an interim solution and also buried insulated piping and power circuit that any future ASHP installation would need. However we have completed our build and moved in at the end of 2017. So now we have an established status quo with known characteristics and run-rate costs. Any future material change should be based on an informed cost / benefit trade-off. However, one issue that really complicates all this is that the whole environment is still very dynamic, and any trade-offs need to take an honest reflection of this: just extrapolating out the status quo can be a real mistake. For example: Components such as batteries and ASHPs are still on the steep part of Engineering Experience Curve and so will be experiencing real capability improvement and price/performance drops year-on-year, so it can often make more sense to defer decisions year-on-year if you are going to get a better / cheaper system as an end result. Take the case of an ASHP, ASHP units cost roughly 5 times the gas-boiler equivalent, with a comparable gearing on installation costs. This is because we are still on the 'low volume, high price' end of the price curve. Even at current high energy prices, I can't make the case to install and ASHP and demote the Willis to fallback. This might not be the case in a year's time. Battery technologies and chemistries are still rapidly evolving, so I double that current Li-based systems will remain in pole position for house-based systems for long (other than perhaps for V2G solutions). I also think that UK Energy Providers will be forced to offer new time-of-day pricing models to create demand-side leveling as the percentage of renewable increases. This will all help, but for us the installed price of powerwall-style batteries would need to fall by a factor of 4 or so, for numbers to add up, as I can for do load shifting on roughly 80% of my high winter-based load by scheduling without any local storage.

I use a Sonoff USB Dongle attached and old Laptop that I use as a VM host and which runs Home Assistant to drive my ZigBee devices. HA has preconfigured support for all sorts of devices including LED controllers, though I don't know if it directly supports this one. However, my suggestion is that you work out what home automation system you want to choose, then pick a controller that is properly supported by it.

You could also just feed a HW tap direct into a drain and then you'd get through the HW a lot or you could ask what your objective are here and modify behaviours accordingly to minimise costs whilst maintaining those objectives. In terms of our DW and WM, these are both cold-fill and have timer functions in-built so 90+% of the these go on overnight to use cheap rate electricity. My aim in having a shower is to get clean, quickly and efficiently. All of this COVID focus on the "right way" to hand-wash reminded me that the three most effective components in removing microbes, dead skin, sweat and dirt are (i) soap solution on skin, (ii) contact time, and (iii) mechanical friction. A high-flow volume doesn't really help here, as this buggers up (i) and (ii). So my strategy is to do a quick wet down (say ~10s), then a full body lather and rub down for at least 60s, then a quick rinse and blade off to remove 99% of the soap and then a final rinse off. Our showers have a 8 L/min click-stop and I probably have under a min flow under this stop limit. We have ~2bar head at normal flow rates so unstopped we get maybe 15-20 L/min but I find I need maybe 30 sec final rinse-off to come out spotless and soap-free, so perhaps 15-20L in total for the shower. Maybe this might seem a bizarre behaviour to most members, but all I can suggest is that I come out of the shower cleaner than if I'd just stood under it for 3-5min @ 20L/min, so I view this latter as pouring money down the drain for no benefit. Or just call me boring old Mr Pompous. 🤣

Not really. The point of an ASHP to pump heat as cheaply as possible. Two things drive this cost per kWh heat pumped: the effective CoP and the unit rate of electricity. If you have an energy-efficient house which has a long thermal time constant (e.g if I was to lose heating now my house temp drops around 1-1½ °C per day) so it doesn't really when you pump the heat during the day, just that you pump enough day-to-day to balance out overall heat losses. The "when" bit becomes: when I can buy it cheapest.

Electrics 2nd fit, Gas, UVC must be done by a certified professional. Some trades require a lot of skill / learning curve so it just isn't worth trying to do then yourself unless you are "in the trade": plastering, slating, bricklaying, precision concrete work, etc. In our case we use a local builder to do our groundworks: we had to drop the entire site by ~ 0.6m to get the headrooms we wanted and maintain ridgelines; that was a lot of 40 tonners of subsoil to dump. (Luckily a farmer in the village was culverting a stream that ran alongside his yard and happily took it all.) He also did the drainage, stone skin and other outside work. We use MBC for the TF, warmSlab, insulation and air tightness. We used some of our builder's preferred tradesman subbies: electrician, tiler, slater, plastering. MBC's structural engineer did all of the structural calcs and worksheets. Internorm did our fenestration. We pretty much did the rest ourselves: Overall architectural concept, but an architect technician (AT) did all of the initial AutoCAD drawing for Planning Applications; these were passed to MBC's TA for the basis of the build drawing sets. Overall project managed, planning submissions, procurement. I was recently retired and had done some (IT) PM professionally, so we were comfortable taking these on. Thermal specification and design; heating implementation (less 240V electrics), home automation. All joinery / woodworking including fitting a custom staircase spanning 3 stories. Used to be an occasional hobby, and I was a lot more comfortable with my standard quality of work than that of my builder's preferred chippie. Fitting kitchen and all sanitaryware. All plumbing, and MVHR, both design and implementation. Also external rainwater and weather proofing. Decorating (though used / paid a nephew who does this professionally for a lot of this). Jan used to run a custom-made curtains business, so she did all of our window hangings. (i) This saved a shed load of money -- maybe 40% of what the build would have cost us if we had subbed out these. (ii) We had far better over design and implementation cohesion and quality because we could consider the issues end-to-end and were motivated to achieve a standard that we wanted to live in. However you need to be realistic: What are your own skills / aptitude experience? For example Project Managers and Architects charge a lot because the work is skilled and time consuming. Doing these functions yourself can save maybe 20% of the total build costs, but you have to be totally honest about your own skill levels here because you doing them badly could end up costing you a lot more. BRegs impose certain requirement v.v. certification and those are primarily triggered by safety / risk issues. e.g you cannot do electrical installation because the Regs mandate that it is inspected and certified by a registered qualified electrician. So even though I have rewired my previous house to the then Regs, it was a lot easier to subcontract this all out to a known and competent sparky. However some here have done the first fit themselves and used an electrician for second-fit and certification. We used an approved private BInsp rather than the LEA inspector, slightly more expensive but better overall because the Inspector was more customer focused, whilst still enforcing the regulations, but we found we could discuss issues with him and he occasionally made excellent suggestion of an implementation approach that would still comply with the regs. For example, I still had to submit and self certify all the required design and test documentation for things my MVHR, foul and potable water (including why my system was exempt from relevant the Part G HW safety thresholds.) I did the SAP-as-designed calcs myself. This was a mistake in retrospect, because the as-build calcs must be registered by a certified practitioner. All of our local SAP firms would only quote for a job lot and weren't interested because I'd done the as-designed myself. Luckily I found a company that was more flexible and were willing to do the as-built submission, but TBH, it probably cost just as much in the end. Time is money for other trades, so you holding the work up is going to lose goodwill and prove costly. We always made sure to have any prep work that we were responsible for completed before it was required. We were helped because our TF + fenestration was erected and weather proof in under a couple of weeks. After that we were largely responsible for all internals at our pace and the builder could get on with the externals. This made the interfaces straightforward and stress-free.