Nickfromwales

If introducing a single zone of UFH to an existing oil boiler, you may also run in to issues with short cycling. This would require either certain rads coming on in unison as heat loss (hall / stairs / bathrooms), or a buffer tank being added to the UFH circuit, or the UVC being swapped out to a thermal store (with DHW coil inside it for hot water). You'll also need independent (additional) heating controls for the UFH'd areas to 'zone' them; these will need set-back times that start sooner / end sooner than the areas with rads. Ahhhh....the joys.... UFH here would be a 'want' vs a 'need', so forget any savings or economics tbh. You either do an overlay system and suck up the inefficiencies or dig out and fit lots of insulation, either option will have cost and performance impacts / pros / cons / caveats to swing each argument for / against, so choose wisely. UFH well installed is the best thing of all, but poorly installed (then poorly performing) UFH is utter garbage to live with. Dealing with draughtproofing will be your No.1 priority in any of these cases, to lower the amount of heat required in the first place, so always consider a fabric-first approach at all times. Further note that the closer you get to 'airtight' the closer you get to needing to fit mechanical (forced) ventilation too, so yet another can of worms to then consider for Part O....!

Stopping at the eaves will leave a huge amount of permeability, so I doubt this is anything to hang your hat on, and if 3-3.5 is the target then you'll have fabric infiltration beyond the flow rates of the MVHR which means the heated air will be getting lost faster that the MVHR unit can recover it, so consider your next move based on the worst case scenario so you don't make any unwise investments here.

Are the radiators and pipework being upgraded as part of this install?

What he said...

Bonded too?

Yup, if it's wrong to love a V8 then I don't want to be right 🥰

We usually ask for a 400mm bucket for excavation, with one service laid either side.

I've heard that single room MVHR is less than brilliant, particularly with regards to actual heat recovery. If true "fresh in / stale out" then trickle vents become redundant / unnecessary. Most BC officers don't have a Scooby-Doo tbh.

I fully-filled my undercrackers when the bill to service my car landed.

They're usually in high-end hotels etc, very nice tbh and no complexity / multi-component failures that often go with these things. In absolute honesty these are the least of anyone's worries, as they are changed for a new (replacement) in around 15-20 mins or so. More of a worry for the bath if boxed in, or the shower unit if tiled in on a flush floor arrangement.

Sadly, yes, as if you ask 5 different plumbers you'll likely get 5 different answers that each party swears by. I just go on 3 decades of doing "what feels right" and the confidence that it all worked well (or very well), as I tend to over-engineer a little for 'Justin' but the results always speak volumes.

You need to be asking the supplier / manufacturer, and explaining the floor construction / UFH situation to get the correct technical advice. This then needs to be conveyed to your heating installer to make sure there is a strategy for preventing the flow temp ever exceeding the max allowable temp (usually 27oC). As for floating the floor, don’t even dream about that, the UFH will 1000% need this to be bonded down if it is the only means of providing space heating. Also, have you calculated the room heat loss vs what the floor is likely to emit (heat-wise) per m2 as there are a lot of disappointed UFH owners out there who haven’t

The impact is severe for DHW, so it needs to be addressed. Apologies for the delayed reply, life continues to get in the way

I made some suggestions to the technical director of Nudura a while back regarding this weakness in most suppliers strategies …..she said that it was a better methodology than they proposed at the time……didn’t get done……not much has changed methinks. Life goes on in the absence of anyone wanting to ‘do better’.

Why would anyone choose a woodcrete ICF systems when ANY part of the structure is below ground? I have ‘experienced’ both Isotex and Velox, and compared to an EPS system they would have to come with free supply and fit for me to entertain ever using them. Sorry. Make a better choice and reap the benefits, is my 2 cents.

At worst this would just require a £20 relay and base to allow the live feed to ‘flip-flop” between the 2 demands. An hour or 2 for an electrician if he knows what needs to be done. Very likely this can be done by just wiring it correctly to the OEM control board tbf.

Not at all. I plumb all these with 2-port and don’t really like 3-ports tbh. The 3-port when used is a diverter valve, not a mid-position a-la a standard 3-port in a regular heating install where overrun is required after a ‘burn’. No reason whatsoever why any competent plumber (or very good electrician) couldn’t sort this in a day (including investigative time). Is this problem new or do you not know if it has done this from day 1? My guess is it is an error from the installer which you’ve not been aware of, ergo not a fault, more an mis-configuration.

I’ve found with most good trades, even the best, there’s still huge gaps in coordination. Not so problematic if you have some kind of background in the industry or have a lot of spare time for attendance, but when left to their own devices a lot of trades fail to work with much synergy / harmony, and results ‘vary’. A good electrician should save you ever needing often laughable “lighting designers”……last one on a project I was on looked like a Parkinson sufferer had a bingo marker and charged north of £3k for it, which the client paid, then I just binned it and did it properly for free within our electrical package. My kids have done better looking things stuck by magnets to my fridge

Yup, that is correct. Cheaper than shoplifting, quiet as a mouse farting in a church on a Sunday during mass, and solid as a rock.

Long bloody work holiday lol. I apologise sincerely boss!

Hi mate. To give you a reality check, this sounds like way too steep a learning curve, in too short a space of time, on an extremely fragile budget (being polite there btw). As above, £160k will get you the keys to a house you can just walk in to and put your toothbrush in the holder, switch the telly on, and open a beer. So, question has to be; “Why not take this simple route vs the leap into the unknown”?

Night and day different for your setup then.

Was the 13kw of solar removed and refitted? Eg you’re not adding to or upgrading the solar setup that you have the FiT payments for?

It does (can) if the WC’s are sharing the balanced feed from the UVC multi block aka control group (PRedV). If the cold mains isn’t great, then I always recommend feeding the WC’s off the raw cold main, before any pressure reducing gets done.