joth

We're using OSB lining for the internal airtight layer on our renovation & extension. I had thought Smartply Propassiv OSB3 would be the obvious choice but just discovered the spec only called for OSB3 and contractor has quoted a basic price, not for Propassiv. They have good experience getting great airtightness results taping on the Propassiv but never done it with standard OSB3 before. I'm getting prices for upgrade to Propassiv, which is my gut instinct to go with, but I'm trying to figure out how much risk we're taking on if we did keep with taping standard OSB? Has anyone here taken that route (or got references to anyone that has) and achieved good results? (Or horror stories!?) Thanks

... except their (£450) DALI extension - presumably if only works via that, not KNX. I see they updated the DALI extension data sheet last month (but doesn't mention DT8), do you know if it's a new HW version? (just asking out of curiosity so not urgent)

I'm drawn by this rationale too. "Fabric first" philosophy of hw cylinders, focus on high insulation rather than smart tech add ons. (And vitally, no dependence on cloud connection to any server not under my control) Looks like the "geocoil" is their heatpump ready cylinder, but can't find any pricing for it https://www.osohotwater.com/en/domestic/delta-geocoil They do list a UK direct sales info so I might shoot them an email/call https://www.osohotwater.com/en/contact

I wondered about this, but when I looked through the WRAS and Building regs requirements it had requirements that if you do this, the DHW secondary return must operate at 60+ deg C or so, and must run "continuously" (or wording around that effect). I could not tell if N hours a day would satisfy this "continuous" requirement, and of course would add another requirement to have the secondary return operate all year even if away on holidays (ah, those were the days when being out the house for a week at a time didn't seem ludicrous). Combined with the excellent points @Jeremy Harris makes on here of the simplicity of direct electrical heating (for towel rads and bathroom UFH) we decided to go that way. To the second part of the question, I'm curious what could stop any heating element work with loxone? Hook them on a 16A relay extension and away you go? I guess a very high end element could have built in smarts that need a manual prodding if the power is removed? So just go for a good value, dumb element.

That report is interesting, as it shows that a standard tank's usable volume decreases as the flow rate increases (as expected, more turbulance results in loss of the thermocline), whereas the Mixergy actually has a slight increase in usable volume as the flow rate increases. Any idea why? Couple interesting points on this from the report: - It states: "The Mixergy Tank is a hot water tank that makes use of a novel inlet diffuser and angled heating element scheme to increase the utilisation of stored water within a domestic hot water tank" - It seems they used a Newark tank as the reference "standard" tank (going on Table 7 & 8) so does make a direct comparison of the two - The tests were carried out by Newark on their premises (but under instruction of NPL), so not entire independent, but sure what more to read into that if anything.

I've got the older Loxone miniserver with KNX interface built in, so only need the one gateway I was 95% decided on Loxone, but the recent (predictable) change in their online shop, locking it down for partner companies only, no retail sales, has given me cold feet. I already have most of what I need, basically everything except a couple more Touch tree switches, so might keep with them. The alternative is MDT KNX switches, and either use the Loxone purely as KNX->DMX gateway or buy a dedicated gateway. I have 30 channels of DMX triac dimmers from AliExpress, which is a very straight forward solution and seems to work with all the mains dimmable LEDs (GU10 etc) I've thrown at it.

Do you have any tunable white DALI LED modules? I have a Merten KNX->DALI gateway which works OK with Loxone, after a fashion, and AIAUI in theory supports DT8 but I don't have any drivers/modules that support it to actually test out. btw I've mostly decided against the DALI because of the costs and additional wiring complexity, so will post up the bits I have for sale at some point.

Just noticed 2 of the biggest passive house certified suppliers have merged: https://www.enhabit.uk.com/enhabit-joins-forces-with-green-building-store/ https://www.greenbuildingstore.co.uk/green-building-store-joins-forces-with-enhabit/ Obviously they both do more than just MVHR, but these seems to be their biggest area of overlap

It'll depend on the insurance company, ours absolutely requires all windows have locks, but they specifically say they'll honour claims if we forget to use them.

To the original question (can I DIY Loxone), the answer now appears to be a clear "No". sigh. At some point since I last looked at their webshop, they've locked it down so now only their Installer Partner network can order direct, and the rest of us have to purchase everything through a partner. At least they still have component prices listed on the website, but that surely can't last very long: next thing will be a hidden pricelist, installers refusing to supply kit unless they're also installing it, and being able to charge whatever markup they fill the local market or your specific project can bear. And then once installed, you're completely locked in with no way to DIY upgrades or maintenance etc. I'd already been paring back the functionality I was looking to use Loxone for, to just the most critical building services like lighting and heating, and was getting familiar with Home Asssitant for less mission critical stuff. But now they've pushed me away completely. Given the current situation, when work resumes I anticipate we'll just want to get the electrics done ASAP so I'll probably scale right back my ambition: make a future proofed wiring plan and come back to it another year with some kind of retrofit.

Some recent thoughts on the very subject here:

Appeal to keep builder's merchents open: https://www.insightdiy.co.uk/news/leaders-of-builders-merchants-offer-to-meet-with-government-over-potential-uk-support/8226.htm Which implicitly somewhat suggests they're closer to be closed down than I realized. This would be real hit for us; our renovation is currently back to the shell and open to the elements on 2 sides, we'd have to do some emergency boarding & shuttering if we should have to mothball the project due to lack of materials. (The building crew are keen to keep going as long as they possibly can)

Sorry I can't directly answer that but I definitely have read on here that there's different categories of permitted development, and even if your PP has a clause to remove PD for extending/improving the dwelling this doesn't remove the other classes of PD. I can neither find that thread nor remember the name of the author, but IIRC it was one of those helpful professional architect types that often help out on this board ? Just to clarify: I have no idea if ASHP falls into which class of PD. That's the crux of the question AIUI

I don't quitefollow this, ASHP are still permitted development even in a conservation area, just a couple more restrictions (must not be on or in front of a wall facing a highway)

They will do, but it must be a graded alarm with an annual maintenance contract (recurring fee) from a registered installer that provides an "URN" reference number (one time fee) for the system. Any trigger must be confirmed (two different sensors activate) and is routed via an alarm receiving center (recurring fee) to triage. They have a three strikes policy for false alarms and such like. If you don't want to pay recurring fees, the best you can do is self monitoring with some sort of system that notifies you on your phone

It would be impractical and perhaps impossible to get a Tesla-battery qualified electrician to rewire my home if I'm not actually planning to install a Tesla battery at this point. I was hoping they'd say something more like "it depends whether you want to plan for a partial or a whole-house backup? Take a look at the UK version of this guide, and here's some additional information to help you figure what sort of backup you might eventually need".

Yeahbut my electrician's first question is "what is the Tesla MIs and their technical recommendations"....

@Dan Feist when I spoke with Sunamp they were adamant their own testing would be needed due to control systems (in)compatibility catching them out repeatedly with so many other ASHPs. I think I mentioned at the time they could just as well test with an existing Vaillant aroTherm ASHP as surely the control logic would be pretty similar. Agree with the other points. I personally don't care tooo much about the cost implicartions of a legionalla cycle. Between PV eliminating it in summer and an occasional blast in winter (or not, per other views on here) we're talking about pennies really. The hassle of getting formal G3 maintenance once a year is more of a motivation to go Sunamp, plus space saving, but offset by the lack of long-term reliability evidence. I'll probably continue to prevaricate and make a panic decision in a few months based on which suppliers actually want to talk to me at that point.

In daytime you need more primary lighting (direct, overhead e.g. downlighters) but in evening secondary/indirect lighting comes more into its own, so +1 to @PeterW's approach of using different temperatures in different lights. Another option we're looking into is dimmable LED bulbs that change temperature as they dim. There was a recent thread on this suggesting IKEA bulbs. Worth a look, very price effective and no extra control complexity needed. Last resort is bulbs that use Bluetooth app to adjust temperature or dedicated Dali fittings that have fully adjustable temperature. They're all are too fiddly or expensive (or both) for me to consider, but a colleague recently redid their whole house with temperature adjustable DALI fittings (controlled from Gira server and KNX) and love it.

Similar. For me internorm, GBS and Gaulhoffer were all similar sort of prices, but weru sufficiently more we didn't even write them down in the comparison spreadsheet. (Unlike OP we were specifically after timber+alu so YMMV)

Do something with the corner castings? No idea what, but my starting point is to design a grid/platform that bolts to all four corners and install on that, then see how to simplify that idea.

While you have them on the phone, ask if they have any published guidance for how to future proof/prepare a new build or rewire for later installation of their system. ?

Right yes it was early in the morning and I not enough coffee yet. I realize now I'd already found the 4.8 figure last month and commented on that upthread, and indeed already done the PHPP experiment too. The new UK spec matches the one previously published on the vaillant.nl website so same findings hold: we'd save 1.5kWh/(m2.a) on PER so about 227kWh/a or £35/a having this ASHP vs the Panasonic. (And discount the Daikin as both uncredible, and no cooling), and a bit more ontop from having lower heat losses of the Sunamp. Add on top there's going to be a delay until Sunamp have tested this new heatpump to certify its use, plus installer availability is so limited, I am leaning towards whatever presents itself as the most trustworthy/reliable option but still open minded it could be this setup.

Looking through the COP figures I'm a little underwhelmed by it, tbh On the 7kW model I see A7/W35 COP of 2.8, which is actually lower than the A7/W55 score (2.9). The higher power units fair even worse at low flow temperatures (COP=2.4). Compared to the 4.52 on the Panasonic monobloc we've currently selected, I'm not sure if the improved DHW performance (with addition of a Sunamp) justifies this kind of hit in heating. EDIT: ignore all that. I was mixing up A-7/35 with A7/W35 due to very unfortunate word wrapping in their spec sheet. A7/W35 COP is 4.8 so much closer to what I expected! I'll put it through PHPP later and compare. Lower GWP is obviously nice idea. But the main issue I've had is exactly zero of the Vaillant installers will talk to me. The only returned calls/emails were to say we're out of their service area (by, like, 10miles). Many thanks again @Dan Feist for sharing this info though. You really got some better contacts there than my attempts managed!

Thanks! We've really cut corners with the main door, selecting the same internorm patio style door as we are using for the kitchen side door. Our front door is not visible from the street (on side of house, perpendicular to the road) and will eventually be covered by an external porch, so really seemed a waste of money getting a statement door. But seeing yours gives me serious doubts as this is exact look I originally had in mind!