joth

You can heat the DHW however you like, including from the ASHP. The point is RHI is for the space heating. If you have additional sources of space heating this will reduce the RHI, but the mix of sources you use for DHW is irrelevant to the claim. (AIUI. Making my claim in 2 months)

You can claim RHI on an ASHP for the space heating only. You don't have to use the ASHP for DHW at all to claim RHI

This was going to be my suggestion too. I was eyeing up various options like this before we took a very different direction in hallway lighting design https://m.aliexpress.com/item/32904917138.html (Note that like a lot of these large fittings this has down lights in ceilings illuminating the baubles from above rather than each one having it's own powered bulb. Figure out which style you want and browse accordingly!) I've ordered loads of stuff from AliExpress now including all my DMX lighting control gear. Only had a couple things fail to turn up but the dispute and refund process solved both of them. As always online, be sure to use a reputable credit card for payment

I'm a fan of anything I can flash esphome onto. This way I can control it from home assistant and from loxone as I like. In practice I use home assistant+esphome as a glorified development environment. I've written a UDP service for esphome that allows RGBW lightbulbs to be directly controlled by the miniserver. Adding socket relay control to this should be trivial and is on my to-do list. Feeding back the consumption data is not so interesting to me as I prefer to do monitoring and logging in home assistant anyway (that's running on a real computer so no risk of wearing out the SD card through high frequency writing, plus the dashboards and higher level analysis are better there) Specifically, I've found the teckin smart plugs and bulbs on Amazon to be good value, and easy to reflash via tuya-convert.

DNO doesn't have anything to do with the meters, they just provide the cutout and 100A fuses and everything downstream of that is up to your supplier(s). When I talked to our dno about this they said it's very common in London for larger houses to be split to flats and the phases then gets assigned to a different flat, with each occupier getting their own choice of supplier on that phase (or 1 phase unused if there's only 2 flats, say)

Bowtie use this technique on several of their retrofit projects you could have a browse through those. In particular I know Kentish town EnerPhit was done this way (I was lucky to have a site tour just as it was on 2nd fix) We have completed a total internal refurbishment to EnerPHit standard of this Semi-detached four bedroom Victorian house. The interior was completely stripped out leaving only the masonry exterior. A new load-bearding timber internal structure was constructed allowing the layout to be configured precisely to the client’s needs. The masonry envelope was then insulated with ICynene spray foam. This completely isolates the internal structure from the thermal envelope preventing thermal bridging from the heated interior to the outside. Moisture sensors have been installed between the brick and the insulation. Bow Tie Construction proposed this solution and we collaborated closely with the architects as part of the design process to develop an EnerPHit solution for masonry buildings that does not affect the external appearance and is cost-effective.

Yeah I'm guessing here, but I had two installers run the room by room calcs and even with me telling them we're aiming for <1 ACH they still put something a lot more pessimistic in. (Understandably -- naturally they're arse covering, and there's comparatively little downside to them over-specifying).

PHPP says our peak heating demand is 2kW, whereas MCS room-by-room calcs says it's nearer 5kW. Having got both spreadsheets, it seems assumptions around the air-changes accounts for most of this. (AFAICT the MCS handbooks says estimates airchanges based on the age of the house and don't adjust that, so high quality retrofits will be systematically over specified, whereas PHPP takes a more optimistic view that the projects will meet the requirements of certification)

When I asked about this, I was pointed to page 9 of https://www.passivhaustrust.org.uk/UserFiles/File/Technical Papers/BRE_Passivhaus_Airtightness_Guide.pdf as one reference for successful use of OSB as airtight layer. That said, in the end I decided to pay for Smartply Propassiv OSB upgrade, simply because we were already spending so much on renovation stripping back to install OSB we might as well pay the £800 extra to use a certified airtight product. Certainly very happy I did that rather than entertain using an additional membrane -- that's probably fine for a full DIY build you can take your time and attention over, but seeing the 1st fix trades come in and beat up the OSB layer I know there's no way a membrane over it would have survived. (These were all hand-picked trades selected for their experience and willingness in dealing with Passivhaus build techniques!) Our first airtest was 0.5 ACH which is pretty extraordinarily good for a retrofit, so I'm happy with these choices. The hope is second airtest will be better again, with the plaster and render on.

Well no sign of the portal still, but I just received the first process progress update from them. Very non-committal... Thank you for applying to the Green Homes Grant Scheme. Vouchers are now being issued. Homeowners whose vouchers meet the required criteria can expect to receive vouchers within the coming weeks. However, we are finding that many voucher applications are incomplete and require more information in order to be approved. As we work through voucher applications, we will contact you to gather any further information required to support your application for a Green Homes Grant voucher. You will receive a separate voucher for each of the measures that you have applied to install. You can only begin work once your voucher has been issued. Any work that was started before that date cannot be claimed under the Green Homes Grant Scheme. You do not need to do anything in response to this email

Similarly, we've gone for MVHR extract above the sink & dishwasher (against a wall also containing the ovens), and Bora recirculating hob in the island about 2m away from the sink. The Bora will vent out under the plinth all around the island, which has about 9m perimeter, so no specific direction or focus for the draft coming out of it.

If you want "something" to come out of all four speakers, I'd suggest split Left to feed F-L and R-L, and Right to feed F-R and R-R. Make sense? It is "nothing.nothing" , as the 5.1 style notation is about the surround compression codec decoding and your 4-point has no codec decoding. It has 4 channel analog input (F-L, F-R, R-L, R-R) and presumably constructs its own sub channel from a combination of FL & FR (and maybe rear too?) Thus the decoder would need to decode to 4.0 in order to create exactly four channels that your 4-point requires as input. Right - it unconditionally spits out the front to L-C-R and that's not use for you (unless you add a center amp/speaker) as you'll loose all the center channel dialog into a blackhole. Depending on the type of movies you watch, this may either be a blessing, or completely defeat the purpose of the upgrade :-) I've got a similar one and it doesn't seem to do Dolby Digital at all, just DTS, but I now see it may be the 2.0/5.1 switch is unreliable (according to some reviews)

Easiest option is use a 3.5mm headphone splitter to feed the stereo output to both "Front" and "Rear" speaker pairs. If you actually want to place the rear pair behind you for some sort of surround sound effect, you need a Dolby Digital decoder. There's loads of poorly manufactured options to choose from on the Amazon, but you need one that allows selection of 4.0 rather than 5.1 surround and most don't support that. Perhaps this one: https://www.amazon.co.uk/XOLORspace-Switch-Digital-System-Decoder-Black/dp/B08527TR78 Says it supports ARC too so you can connect with hdmi or optical

(sorry too long a post for me to pick through it all right now) I don't understand how you can say I'm completely incorrect. My statement was that the intention of RHI is to increase the number of trained suppliers. This is literally word-for-word relaying what my friend that used to work at BEIS when it was setup told me. Same as Solar PV RHI, they set it up to increase the network of trained professionals, not to make the systems cheaper per-se. I did not claim that this policy is actually working. It's too soon to call, incentives like this will take many years to work through, but right now the evidence is very thin that it's working. Certainly I had incredible trouble finding an installer, and numerous friends/neighbours/acquaintances have asked me for advice simply because they don't understand the technology, can't find info on it, and get the run around if they try and talk to suppliers. And GHG has added acute pressure that makes this even worse, not better at all. Beyond all that, people pointing out their own DIY installed worked out fine is not evidence that it's a scalable solution for the majority of the country to do it. It's once you get out of early adopter and into mass-market that the problems and misinformation highlighted by the OP really starts to get peddled about.

I think you already answered this. 1/ for whatever reason, the evidence is that people regularly install poorly designed systems that under perform 2/ so we can deduce it's hard to design a system that is guaranteed to work well 3/ most lay persons (and self builders) lack the skills and experience to be sure they can design their own system. It's probably the only system they'd ever design so not worth formal training on how to DIY it 4/ there's a dire shortage of professional system designers with proven track record. RHI is explicitly designed to solve #4 (NOT to reduce cost of ownership, as people tend to think) which in theory is the way we (as a country) get out of this conundrum BUT it puts up the "up front" cost of ownership, which combined with the drawbacks listed above makes it extremely unattractive idea to the cautious customer

... that said I also see I2C on the header and 5V supply and a 3.3V regulator so there's plenty of alternatives to explore

To get you started, there's a nice little clue stenciled on the PCB next to the Comms header.... Nice work Phil ?

Here's me testing the rain sensor. Fortunately for my arm, it is very slow moving https://photos.app.goo.gl/aoMvLzQYa9YeGb4e6 (I'm stood on a three storey scaffold to get this high in the vaulted ceiling)

No, I have 3x Fakro. I got quotes for roofmaker, but the price: performance favoured Fakro

Has anyone seen any sign of this GHG portal arriving yet? There's constant adverts on the radio for the grants - wish they'd spend the money on actually making them work rather than recruiting more mugs to a nonexistent scheme.

Batteries should still reduce in price over coming years, and some systems allow you to buy small and incrementally increase capacity. So for your goals, I'd do the 8K now and live with it a year or two and see how much juice you are exporting and make a call how much battery to get down the line (if any). Correction: this in not what I would do, it really is what I currently am doing. Also: if the goal is planet saving it is immeterial if you're using the home grown PV electricity yourself or feeding it to the grid. Each additional kWh you generate is one less needing to come from gas. (Caveats abound)

Recessed meter boxes can be a pain for thermal bridges/breaking insulation and airtightness. I've just laid a duct into the garden from the garage that I can pull cable through in future, and put a few basic lights and plenty of sockets on the back of the house. Generally I'm avoiding wireless lighting control but for outside feature lighting I'm happy to make this compromise. Fwiw long dmx runs can become flaky and hard to debug, I'm using a DMX amplifier/splitter to keep zones separate and trying to keep most of the decoders nearby in the main electrical cupboard

Roofmaker and Lamilux were the other two we looked at. Former is cheap but not many PH certified options (flat roof only IIRC), Lamilux seemed very expensive. https://roof-maker.co.uk/rooflights/pitched-rooflights/luxlite-pitched-rooflights/

Yes, we went with 1x of the pitched roof and 2x of the flat roof lights. Installed a couple months ago. So far so good. My only gripe is they don't have any electrical connections for remote opener, it's z-wave only. The pitched one is over a 3 story void and I'd much rather not rely on wireless to control it. (not least because if I needed to pair a new wireless controller to it, this requires manually pressing a button on the window anyway). So I've cobbled together a wired 'remote control' of sorts by extending the wire that connects to the built in buttons, so I can relocate them. but otherwise, all good!

I have a fan coil in the loft. I was just going to put the pipes in now but the ASHP installer said he'd connect it for no additional cost so I went ahead and got one. Ask me in 2 months if it works! More info here: