Nickfromwales

Set them down on cardboard / folded dust-sheets, or it'll be a zero coat finish . You'll need to unpackage to inspect for damage BEFORE installing or you can't return them.

Stelrad are (were) good when I was installing gas CH, but lately I bought a Kudos rad ( B&Q / Screwfix ) for my sons room and they are much improved. The number 1 thing to NOT do ( or to allow to happen ) is to put the rad down and scratch the paint on the underside. I always put these down onto folded dustsheets and cardboard to make sure the paint stayed intact. The cause of rads rusting out from the bottom up is them being set down onto floors, without protection. Next place to look is around the disposable blank blank plugs which are there for spray painting, as some will leave bright steel exposed as the paint process was shart. If you see bright steel, expect rust to soon follow. Touch up with white Hammerite (smooth) paint and you'll be right

I just find them acoustically transparent tbh. SIP's roof is the last choice for me, with the latest architect being dismissive by saying "the interior will be connected to the outdoors" which actually meant when it rains had you'll need to turn the TV up. I pointed this out to the client before the ceilings got closed off, and they agreed to spend some more money adding 100mm of acoustic insulation to control the issue, as best as could be achieved, retrospectively. A cellulose blown frame and roof, al-la MBC / WPH is graveyard quiet by comparison. These are genuinely miles apart in performance. That's not guesswork btw, that's from being stood inside them and being able to tell the difference.

Avoid a SIPS roof. Noisy as feck.

You may also do well in asking Adam Wilkinson (Wilkinson Passive House) for a quote. One of the rare few who are meticulous but not 'champagne money' to be so. I am also a huge fan of MBC btw. They are QUICK! Both offer turnkey solutions (foundation > frame > insulation > guaranteed airtightness score) which means they have to produce the minerals SIPS fails to impress me tbh. Would be my last choice also.

If the water pressure is low, fit a 28mm single check NRV with 22mm internal reducing sets to go onto the 22mm pipe. https://www.monsterplumb.co.uk/yellow-brass-fittings-plumbing-3-part-reducing-set-28mm-22mm?gclid=Cj0KCQjwuNemBhCBARIsADp74QTP_RTBfjKXlco3sqsVMfzwwNM2VZD6XPgsquJDBtCMdL0ZOrihwYYaAsvyEALw_wcB

This falls into the realms of an UVC retro-fit. Done loads of them. Get the PRedV at the stopcock raised to 3 bar, as at 2.5 it will be quite restrictive. Install the control group / PRedV as per the MI's, local to the cylinder, but the one thing that all buffoons forget is to add a single check NRV to the hot outlet of the UVC. Do that and you are 100% kosher. . Warranty will be intact with that all done.

There are many ways to skin a cat

Comes with a lifetime warranty then.

Item 4 is the concern. The flue is called “coaxial” as in the products of combustion are blown out via the inner 50mm or so section whilst outside air for supply to the combustion chamber gets sucked in via the larger outer ‘ring’ of the flue. There’s an air switch that needs to see equilibrium between these pressures or the boiler locks out, thinking that one or other is compromised. Safe in that respect, but the way the original installer left this, especially without the cage, is just horrendous. Glad you’ve seen a positive outcome, and I still share the same concerns as you over the pump, but the MI’s will always take precedence over BCO or GSR. The difference between good, or OK I guess!

Spoil yourself lol.

Yes, but 120mm is a lot for perimeter insulation. 50mm would suffice, and will retain more heated m2 of floor area.

An accumulator is like a battery, and it’ll charge up to the max “power” that it has available. Cold mains enters your house at higher static pressure at certain times of the day (usually higher overnight at 2-4AM) so those are the peaks that you’d want to harvest in the accumulated volume of stored energy (water pressure) for use when you wake up with the rest of the world and they use the water ergo you’ll otherwise suffer lower pressure at peak times. To maximise stored volume in the accumulator you need to adjust the back-pressure in the vessel to allow the water in, so you need to know max pressure so you can set the pre-charge accordingly.

The transition from ‘old to new’ seems odd, which may have left a step inside the pipe. Hard for us to comment / judge tbh as these are German standards and fittings not UK.

If I’m in a hotel and the fire alarm goes off, I get out of bed and lay on the floor. Unless it gets to north of 45°C I’m not too concerned.

RCD to lights and sockets, yes, MVHR normally in the plant so would prob be one of the last trips to go. Nobody has front-of-house RCD CU's anymore, do they? Possible if it's a retro-fit I suppose, but during most conversion / refurbishments the CU needs replacing to get a new cert done on the electrical adaptations. All relatively academic as the rule is, see a fire, GTF out. I am just saying to preserve the dwelling, whilst waiting on the fire brigade, stopping air getting in will slow the fire down a lot.

.....fan the flames by supplying fresh oxygenated air in abundance! For preservation of the fabric of a dwelling, you'd discover the fire and close that compartment off as best as possible (close the doors) and get the hell out of there, and then raise the alarm. If the meter is outside then yank the fuse to the house to shut off the MVHR. MVHR would not evacuate smoke, no chance. Dedicated smoke evacuation fans for stairwells etc move huge amounts of air, whereas MVHR at trickle is like a squirrel coughing. You may be asked to install intumescent air valves (ceiling diffusers) but most are just happy with fire-rated spots. This will soon change I believe, as a ceiling should be 30 mins FR throughout. You can buy a self-adhesive intumescent strip to apply to the internal bore but you'd need prior approval from your BCO before assuming it's fine to go with that.

https://www.screwfix.com/p/monument-tools-mains-water-pressure-test-gauge-11bar/82412?kpid=82412&cm_mmc=Google-_-Datafeed-_-Tools?kpid=KINASEKPID&cm_mmc=Google-_-TOKEN1-_-TOKEN2&ds_rl=1244066&gclid=Cj0KCQjwib2mBhDWARIsAPZUn_nCdrUSQHC88zTNOQI8V5NfpgJIhXydzHSQnpCFQWeV3Y66aEvcMT0aAks0EALw_wcB&gclsrc=aw.ds Whack that on the outside tap / washing machine feed etc. It's 3/4" so you'll need an adaptor to get onto 15mm pipe or a 1/2" thread. You'll need to put a double-check non return valve on this and leave it overnight. The non return allows you to capture the highest 'peak' pressure available ( usually around 2-4AM ) to survey this correctly for an accumulator. Accumulators live in the plant room, or garage, utility space etc as these are nominally 200-300L, so quite big.

That will give you the flexibility to add another phase if ever necessary.

Defo 2x radials, but 15mm to the shower will be fine. I fitted a crica £2k Hans Grohe shower in a clients build and the water flow from it was just silly (huge amounts). I did install a 300L cold mains accumulator there though, so you may want to consider space to retro-fit this if the shower dips when a tap is opened elsewhere in the house simultaneously.

All except when the hot water is FOC from solar?

+1.

Try a B&Q, as the larger superstores carry all sorts of weird and wonderful plastic trims (located where the steel and alu trims and box-section / sheets etc are).

I routered the tops of the joists in my mates house, donkeys years ago, just enough to run about 50m of 8mm microbore directly under the chipboard (P5) deck. It was connected to the CH flow and return and was balanced with a single 15mm gate valve which was mounted under the removable bath panel. AFAIK, still works to this day, and I'm talking 20+ years ago. Zero insulation (as it was 1st floor / within the heated envelope anyways), and as the pipe was toasty hot the heat got through. Makes me shudder when I think back tbh, but this was a quick and easy way to get the result when there was a budget of <£50 lol. There are P5 deck boards available which are pre-routered, but I would suggest maybe contacting Wunda and asking them to design & supply a system for you that suits your exact circumstances. They give comprehensive support upon you placing a deposit.