Nickfromwales

Where can I buy one of these bad boys????????? I haven't baited as I have a dog, plus I don't like the idea of the Kyte's or neighbours cats snacking on poisoned rats.

Because you can't beat a Greggs mate

The mechanicals will always need replacing, that’s just acceptable as things that move wear out. The backbone (such as UFH pipes etc cast into screed or slabs, plus MVHR ducting set into the frame and fabric of the dwelling) is where you should focus concerns of “ultimate longevity”. Most build systems have to withstand 50-60 years of occupancy and ‘use’ but that’s mostly for sub and superstructure; the pretty stuff can be changed retrospectively, and one can assume a full cosmetic makeover (x2) in a 50 year span, to allow for end of life or keeping up with modern taste / style etc.

Or

Seagulls need a massive cull too. Had 2 of my kids food out of their hands, and a whole pasty literally as I was about to pop it in the pie hole. Just heard a whoosh and a flap and the damn huge thing was sat on the floor in front of me trying to polish off a steak bake in one gulp. Queue one angry Welsh plumbers right foot and off it went sideways. Cut my sons thumb open and took an entire Big Mac off him. In Asda a few weeks back I had my shopping loose in a trolley and a mate stopped to chat. He said to look behind me, where another flying rat was ripping my shopping apart. It grabbed a 2x 12 slice pack of bacon and attempted lift off. Just before I got to strangle it, off it flew. The beak had gone through the plastic packaging and right through 10 slices of bacon, ffs. These types of vermin are rife and something needs doing.

Cocker spaniel. Mine has seen 2 big bastards off in my back garden. Feckin things are rife everywhere tbh. Running across the roads early evening, largely because lazy twats keep them fed. Neighbours with open compost heaps and allotments don’t help.

The units I referred to would do UPS / EPS in a black or brown out, where the 50hz metronome from the grid goes bye-bye. AC coupled parallel inverters would instantly go into island mode and shut down. Hybrid units would allow the 50hz signal to be created artificially, and then the solar and batteries would perform as normal in a power outage. You can even then connect a genny to charge the batteries simultaneously if you want to use a lot of power / sunshine isn’t suffice. Lots of different products / options / scenarios / solutions. Best to choose inverters that offer export limitation too, as at >253v your inverter is supposed to switch off.

Chaps. AC or MVHR?

Yes. It’s quite common practice amongst the Chinese stuff. Typically you’ll have a master unit that provides the 50hz metronome to the slave units, linked by the AC signal or a cat 5 cable. Been a good while since I dipped my toes into this stuff, so I expect a lot of the more reputable industry standard manufacturers are also ‘parallel capable’ by now.

Why cable tray? Lots of expense and faff. All round patent band is fine for bunching and laying, and clips are less time consuming than hundreds of cable ties. Seems a massive ball-ache and cost for very little practical return? You’ll need spacers behind the trays to get cable ties in / out, so further projection outwards too. Rows of 38x 25 and 38x 16mm trunking would be quick and simple, using the self adhesive to lay these out and then a few mechanical fixings to corners and joints where you’ll be pulling on them.

Kind of contradictory? Easier said when you’re in the industry but when we’re advising first time, novice self builders then what should we actually be saying here? Cautious approach, manage risk, appoint liability, measure twice, cut once.

Don’t bother with a duct. Sharp sand or pea shingle below / above. 👍🫡

That’s only true if you’ve gone for a single thickness raft, on good ground, and with MUCH thicker concrete. That’s when you can say the loads will be spread out, so what is your actual foundation detail? Point loads are almost unavoidable, unless it’s a small dwelling, they just become less of an issue with one beefy slab. One of the one’s I’m on currently (MBC PH TF + passiv raft) had to have 2 sizeable pads installed under the EPS level, to take the posts (x2) used to break up the weight of the ridge beam. People don’t use terminology well, as raft can mean a few different methods for that one discipline. An SE is absolutely necessary, please don’t assume otherwise

Not if you’re renting to build.

In winter they’ll have masses of cold air infiltration and bump their heating bills up.

You, sir, are correct. I now routinely dissuade anyone from 'diverting' excess PV as these days it's either going into a battery or they're getting paid for the less complex method of selling and buying back. KISS at its finest. Hoooooooooooooooooooooooooooooooowever....... I would like to interject. In terms of promoting longevity for ones ASHP, I suggest that my clients use the ASHP at dawn, and again at dusk for recharging the DHW, and only topping up at midday off the grid, via the immersion, if it is at all necessary. I dislike the idea of having the ASHP jump from a relaxed state of cooling to a panic state of DHW recharging, and the subsequent downturn in COP. I like to look holistically at how the M&E is presented at the design and concept stage, but furthermore, how long the homeowner will have a reliable system that doesn't need replacement prior to it delivering a ROI. Most ASHP's don't come with a warranty longer than 7 years, which is pretty crap, gas boilers around 10 max, so anything simple that can stave off a premature replacement of a bit of kit in the multiples of thousands, is a worthwhile pursuit imho. Kicks the beloved BUS grant saving into touch if you need to replace these any sooner than expected.

Usually PV would sort that, or just a midday blast on the immersion heater, direct from the grid, so the cooling can just plod on in the background.

They get it all year round. We don’t .

Agreed, but it’s a little like being imprisoned by the sun, and also that’ll be on the handful of nice days where you want to be able to look out of those lovely (and very expensive) glazed elevations, to the views outdoors. In the villa we stayed at in Faro (Portugal) there were a few days where dropping all the external shutters was necessary, as well as AC running, but it was horrible to sacrifice the views. For those current projects I’m on, we’re using solar reflective glazing, and the blinds etc will only be needed for privacy. The AC on these will only react to a slight rise in temps, and will have very little to do, so it won’t be a cure it’ll be a prevention.

Depends on whether the one without had trickle vents? You know me and my impartiality lol. “Resistance is futile” 🤣

Sorry, but this is barking mad. They're not "nice to have", they are a B Regs mandated requirement in an airtight house. AC just recirculates the same air in the same space, it doesn't dump heat or moisture or stink to outdoors. If someone has made an airtight home and doesn't install MVHR, or worse that they have installed it but don't use it, then they must be nuts.

Are you cooling the GF slab with the ASHP? I guess you intend to retro-fit the downstairs ones if you deem that necessary?

Getting the cellulose pumped isn’t cheap either. It’s good, but rockwool + DIY will be more cost effective.

It’s Friday. Let’s settle this at the pub!

It’s all about blame / risk / return visits and arguing over who’s part of the install or kit is to blame. Good luck, but I’d walk away from that job every day of the week.