Nickfromwales

If it's a true buffer and has no immersion, you can blank the T&PRV as it will be already present elsewhere in the system. The buffers only need G3 and T&PRV if there is an immersion heater installed. I've just installed one, last week, from Telford. It came with the empty 1 3/4" immersion boss and the blank 1/2" tapping for the T&PRV to be screwed into, but neither are wanted or required as it's a buffer only. Both will be blanked off, and only the UVC will need G3.

Hi. Firstly I would completely discount your experiences with the rental and what you have there, which I assume is a retro-fit system into a property which is not airtight at all and has trickle vents / leaky doors and windows / structure / cold ventilated roof etc etc. We can only advise for the property that this system is aimed at You cannot manipulate single spaces unless it is by temperature, by inclusion of inline duct heaters in each room. A single fan provides airflow, so different air speeds are only decided upon commission, so the system can be balanced. Once set, each space gets a set input or extract volume of air, and the whole house is either on trickle or boost. There are other types of system that may be of better compatibility to your current remit, but before anyone can advise further we would need to know a few things first; type of dwelling - airtightness score if airtight - is MVHR mandated or a choice purchase?

+1. Patching is putting off addressing what is causing the issue in the first place.

Hi Graham. The only reason it gets up to that temp is because it's a heat trap, and the heat cannot escape. If you tried to tap that heat off for directing elsewhere you'd cool that space in seconds, and would have spent a lot of money on an idea which would produce zero yield. If this were a certified PassivHaus then there would be some useful energy taken from this and added to the math, but not for a regular brick / block dwelling I'm afraid.

Ah, just looked again and I think you will need to go the wool route + air gap as there isn't a lower OSB deck under the furring pieces. My bad, but I can blame the good people of Brewdog for their game-changing Punk IPA. Why not go 50mm of PIR then 25mm service battens for cables, and use flat panel LED lights such as Xcite from CEF vs regular down / spot lights? You'll only need to scallop the PIR slightly to get the transformers in, which will be of little to zero detriment. https://www.cef.co.uk/catalogue/products/4501996-8w-led-downlight-white-4000k?gclid=Cj0KCQjwmtGjBhDhARIsAEqfDEfRUXBbV-rtoRKAKUFI9HandcRD-tQnk9Gc_yo19B-gNVQTcpOgUWUaAgi1EALw_wcB&gclsrc=aw.ds Those lights are the thickness of plasterboard, so you can span a joist without a problem (if you need lights to be where they 'need to go' and a joist prevents the OCD monster from being satisfied). I use them on most jobs and am super happy with them, as are the clients.

I'm about to drag one such company backwards through hot coals on my clients behalf. They may as well have just sat in the car vs walk around being pretentious and self-inflated non-important wombles, tbh. What they've signed off on has since been exposed as is horrific. They've clearly just looked at the lipstick applied by the builder, who I have had sacked, and now we are JUST about at the end of a long and expensive journey putting his utterly fecking garbage works right. BCO is the ONLY tenacious and 'particular' guy on this site to date. Apart from me that is!!

PIR is typically 140 IIRC so quite a difference, but PIR at 140 is way overkill for a raft etc.

Just remember that there are short and long staples Short staples are usually specified for PIR, but won't do jack in EPS. Specify long staples, and bang a load in, particularly on the bends and returns. The trick is to use you body weight to hold the pie down when turning / bending, and do not step off until the bend is formed and you're back on the straight. Expecting one clip to hold as you continue to bend the pipe will never work out. Use the longer clips for everything is my advice.

Hi, and welcome. A word of advice.... IF you do find a plot, tell NO-ONE until you own it! London is so densely populated, apparently the rats are saying amongst themselves "You know, you're never more than 5m from a human being"

Just make sure you zip tie the ducts tight to the lower chord so the cellulose goes over the top of them, bringing them into the insulated envelope.

Whack the ducts in, install a good quality airtightness membrane, hold the membrane in place with service battens at 300mm o/c's, and pump the bugger full of cellulose.

Happy days. The external was an "if" so don't panic about that. All looks good, but lets delete the assumptions All voids in the actual upstand need to be packed solid with rigid PIR. Foamed and foil taped to leave zero gaps. The joist depths are to be filled with rockwool / other?

Yup. Something like Marmox on the outside would help, but not essential. If you can get a 10mm board outside then do that too. The only thing I'd add is some continuation over the upper timber of the upstand, as you don't want any (ideally) of that meeting room temp. The issue is exaggerated here because heat will rise, plus moisture, and they'll both be trapped here and fighting it out against anything 'cold'. More Marmox with a chamfered tuck into the angled section would be beneficial.

Relax, we promise to not let you feck this up The worst cold bridging would be between the timbers at the top, and the plasterboard. Easy solution; use Marmox at 25mm thickness instead of the plasterboard and plaster it directly. Stuff everything with rockwool immediately surrounding the upstand, and Bobs ya Uncle. Not a single mention of Fanny, that would be rude!

Yup. You catch on quick, Sherlock.

Yes, the rotating waste is (was) a revelation. Have you looked at Diamond wetrooms? They have a clever tray which you pick up and rotate 180o and the trap moves 'sides' of the joists.

A decent tiler can make just about anything work.

You can do the same with regular tiles, just the cuts have to be a bit more inventive. Also, depends on whether you've gone for linear trays? Not too late to change and mosaic? Or is your preference for large-format tiles only?

All the area around the actual shower former (Wedi) is slightly elevated compared to the perimeter of the former highest point, eg so I could bench the mosaics in and have a fall all the way from the towel rad to the drain.

Eh? You cannot tell where the former ends if it's being tiled over?

I'd say that's possibly the slates cooling down each evening. Probably be worse while we have some sunshine, and almost disappear during winter. May settle, as new houses do tend to do these things.

Flow will be flow, regardless of duty, so the energy in the pipe gets preserved and delivered where it needs to go to.

You just bench the missing 100mm in with tile adhesive and an off-cut of cement board / other.

One pipe leaving will be flow at the manifold temp, and the return loop will obvs be at the lower temp. Deciding which pipe runs where offers some minimal but additional manipulation of this distribution. In a PH or thereabouts it does become almost moot as the slab will almost completely uniformly acclimatise and there will be very little difference between the two. I only insulate the pipes going to the far side of the dwelling from the manifold, mostly to keep whatever is in the pipe, in the pipe, until I want it 'out'.