Nickfromwales

What size joists are going in the floor, and how much insulation are you installing? The UFH will need a significant amount of insulation under it to perform well without huge running costs. What will be supplying the heated water? Existing heating system T'd off to a single room UFH kit?

Shut off the UFH so the primary's are only flowing the the FF heating eg so whatever the pump has to offer is only pushing water to the FF rads. Leave that run for an hour or two and revisit to see if the air ( which is the problem here for sure ) has made its way into the rads. Do you have / did the plumber install an AAV ( automatic air vent ) on the upper ( flow ) pipe feeding heated water to the cylinder?

That’s the problem with a heat pump Nobody knows until you fit it in it’s new surroundings and switch it on. Ambient air temp, target flow temp, external air temps etc etc all go towards the output power. Output power is only ever stated as a hypothetical, and the design / suitability / expectations get managed by “running the numbers”. Each instance differs so it’ s down to the individual circumstances which will dictate ‘power’.

So basically a 2-speed system Where do you think the “noise” goes?

Any of this get you out of the 💩? https://www.tlc-direct.co.uk/Main_Index/Ventilation_Index/Ducting_Flat_6/index.html

12mm is the smallest gap I would ( now ) allow for ( after being force-fed window installation do’s and don’ts ). It was only after having no choice other than to step in and help a client out with a ( now evaporated ) window companies aftermath(s) that I now know this. The fixings are cranked or nearly straight, so you choose the correct brackets / fixings for the job, simples. Peo0lecoften turn up with whatever they’ve got left over / whatever saves them buying the correct stuff in, so question everything and settle for nothing less than the correct fixings and the job done properly.

Rock wool is fine, the sound issue is non-factual. I recommend installing 20mm too much of the rock wool to make the plates become a little ‘distended’ and promote great surface to surface contact. My preference is to get to the underside and staple the plates to the deck boards, using thousands of staples to keep things in place for the duration. Can you access these from underneath?

Usually indicates that the openings weren’t big enough for windows? Nope. I’ve recently had to organise the removal and refitting of a load of Rational and Velfac units, and the original fitting crew used “universal” plates which were a complete bag of shit. The replacement fitters I drafted in took one look at them and just conformed what I thought. They then produced the proper brackets which actually lock into the frames by design, almost not needing screws at all, by offering them up parallel and then inserting into the profile of the frame, and then the bracket gets rotated 90° to lock the bracket into the frame. Rock solid. Anything less is a huge bodge. Drilling through the frames with concrete ( or other ) screws is the very last option imho.

….that he was a salesman. They won’t tell you that there are better / more cost effective / more efficient / less obtrusive solutions to the same problem, as their job depends on sales to feed their kids. Ergo, their product is a good idea.

If you can tell me you’ll notice gaining 2.5mm then I’ll buy the drinks 😜. You’ve asked about acoustics, the 15mm PB will help. In case you’re snowed under, I’ll put this into context; eg that’s less than the thickness of 4 credit cards.

The garage temp wouldn't drop if you vent the 'very cold' exhaust air to atmosphere. You'd need a transfer grille in the external wall of the equivalent size eg to input the equal volume of 'fresh' air as the exhaust expels ( I'd recommend 20% bigger to stave off resistance and risk air being pulled from the house ), and this would then only allow air as cold / damp as outdoors to arrive at the garage interior. To be perfectly honest, I think the heatpump will suck the available heat energy out of the garage in a matter of minutes, and the exercise is flawed / pointless as the CoP will then drop like a rock.

First question is, have the studs been installed at 400 o/c? 600mm centres is no good for a bathroom. If so, I’d say MR PB at 15mm thickness and tanking will be bombproof 💣 . That’s how I’ve done every single bathroom that I have been in charge of the specification for, and that’s served me well for over 25 years of bathroom fitting / tilling. Just make sure you have a PB ( drywall ) screw ( 32mm long ) going into the studs every 120mm and it’ll be rock solid.

Fernox TF1 was my weapon of choice. Thought the expensive ones aren’t worth the money.

Yup. Hot water via diverter is numero-uno, EV second, batteries last if you can 1000% justify it.

Likewise.

Big hairy load of bollocks. PM me your plans and a Google earth image showing north and I’ll work it out for you. Then, you will be buying the beers ma’ G.😎🍺

If a 4kWp system is generating less than 3.48kWp at year 30 it will be replaced. It is very simple. There is no grey area, just facts. No smoke and even fewer mirrors. The situation is; the panel ( manufacturers ) won’t let this happen. Underwritten by a company which doesn’t want provoke disgruntlement, or have to run around replacing thousands of systems at their own cost.

But very easy to consume the residual ~2kW in winter, that which the 10kW system will then only provide. Or less. Or none. If you want winter generation you have to max out and accept the export in winter, it’s just a matter of finding the “sweet spot”. Economy of scale says it’s cheaper to put more on when you’ve mobilised a company and paid for scaffolding etc, so I’m an advocate of this policy, and with EV’s on the horizon, or already owned, you cannot have too much PV afaic. If you have “his and hers” EV’s then leaving one routinely tethered during the day, whenever possible, is a great way of deleting a domestic battery from the capital expense, and absolutely maxing out on self-consumption. My philosophy on the “bigger is better” approach is as so; For all the electricity you then don’t buy in summer, plus the hot water you don’t heat, plus then the increased longevity of your boiler / ASHP ( from it going into ‘hibernation’ for around 6 or more months of the year ) all added together goes into a hypothetical glass jar. So you have made yourself energy rich in the summer months / times of discernible generation. You then take that saving and use it to off-set your wither heating costs / inevitable draw from the grid during times of poor generation and reliance on the grid. That ‘pot’ is as good as cash, so can go towards either gas or electricity based heating systems. After that ‘pot’ has been exhausted, only then do you go back to absolute grid reliance ( less the 0 - 25% winter solar generation ) making for a very wise investment, imho. Factor in the few quid for export, which can be improved via Agile etc, and it’s a no-brainier to go large’. Further consider that the PV will go much further in winter if it’s diverted into a heat pump, so that residual ~2kW could then be producing as much as 8kW of heat energy. If the pockets are deep enough, “go large”. Amen.

The ‘premium’ panels we use ( Solarwatt ) have a 30 year performance guarantee. That states that they will still be a MINIMUM of 87% efficient 3 decades from now or they’ll be replaced for free. That warranty + guarantee is underwritten by BMW ( as they own Solarwatt ), eg “worth the paper it’s written on”. So my panels will still be up in the 90th percentile in 30 years from now or they’ll be replaced for free. I expect my panels will still be putting out around at least 50% in a half century from now. The longevity is attributed to the glass-glass design, where the solar element is hermetically sealed away from atmosphere, bonded between two layers of glass ( laminated ). It’s the only panel I know of that can go coastal without any degradation, whereas “others” will state not to install them within 12 - 15 miles of the coast. For a lot of installs the RoI will just get better and better; as the price of electricity goes up, your break even comes down. All the surveys we do allow 50% or more redundancy in the purchase price of electricity, ( IIRC that assumes 17p/kWh ) so a) the breakeven point ( RoI ) is actually much better than we state, and b) the self-consumption figures we state are based on 50%, whereas most are using a lot more “in-house” and managing / minimising their export far more scrupulously, FURTHER reduced the breakeven point. The year that you’d break even would be just into double-digits in most scenarios, if you’ve a straightforward mono-pitch single array, with prices going up by around £1k if the array(s) are fragmented over a couple / few elevations ( so have to be multiples of strings and all optimised ), but as electricity prices go up, your breakeven point comes down. That will continue to get better and better as time goes by. Time for you to dust of what you think is a poor investment old boy

About £8,500 worth of kit if NOT optimised, so ~£4,500 - £5,000 installation costs ( not labour costs ). A bit heavy tbh as a standing seam ‘on roof’ is a pretty simple install if all on a single mono pitch elevation?

TRV’s are cheap and reliable, and reasonably accurate tbh. Been fitting central heating for nearly 30 years so I’ve installed ‘a few’ of them. Manifolds are fine, done plenty of them to rads via actuators / wall-mounted room stat per room, but a bit OTT tbh. I mostly employ this type of system strategically in major developments / builds / refurbishments so you’re not continuously draining down and re-filling as the project progresses. Why are you so averse to standard series plumbing? Copper pipe with soldered joints are good for a minimum of 30 years, and I have hundreds of these types of installs under my belt without issue. Yes the odd leak here and there at the point of commission, but no different to any other system. Guys installed with Pressfit for me the other day, 2 failed joints, and a PITA to cut back and re-make the duff ones as the pipe gets compromised with the compression of the joint. Soldered joints; just re-flux and sweat it again ( if it has leaked from the first fill up ). Zero manifolds, additional pumps and controls / manifolds wiring centres etc if you install ‘traditionally’. Remember that you can go for smart TRV’s and “whole of house” smart heating controls for not much money.

Dead simple. As you say, it just gets retrofitted. It gets inserted into the correct sized gap and ‘works it’s magic’ from there. Your brickie will need to be very meticulous when running / returning the brickwork and they need to leave you the correct, continuous gapping to allow this retrofit.

+1.

Amazon for those vacuum sealed big bags?

I can ask a mate, but tbh I’ve not done a job in Wales for over 4 1/2 years 😵‍💫 so a bit ‘detached’ from my old pool of fitter / mates in the trade here theses days. I’ve cut a fresh set of grooves in the bloody Severn bridge. @connick159 what make is the ASHP