MikeSharp01

Again I think the units are quoted per fan, so you need a bit less - 75L/s plus you must work the system so supply and extract are handling the same volume otherwise you will get a rise in pressure across the house. You need to decrease the supply or increase the extract - naturally ensuring you stay above the statutory (Building Regs) limits.

We are looking at this right now and we have been told, 3 sources and here, that you should aim at the unit running between 50 & 65% of max capacity in normal mode.

Found this quote on Google: but the associated link does not work. "ZIPLEVEL® is a high precision pressurized hydrostatic altimeter. It works much like an aircraft altimeter that measures the weight of the air above it except that ZIPLEVEL does not use the atmosphere to measure elevation."

You do wonder don't you!

PS there is also the old adage of keeping the flow velocity in any duct below 2.5ms for reason of noise.

I think you only need to do the extract side of the system as the supply has another fan and to keep things in balance will deliver the same volume of air (so you will need to adjust it down to 57). So each side can be independent and that will sort of halve you extract pressure drop to 90 (ish) much better and your supply at about 140 but each fed by their own fan. Least I hope I have that right as I have always assumed there are two systems and the pressure unit ratings are for the two independently not added together.

How did you work this out - did you include the incoming / outgoing ducts feeding fresh air in and stale out to the atmosphere. Also remember that runs in parallel don't just add up.

but are tidy targets like anything else fixed down the location of which is known!

any chance the plaster board is supported as shown?

Ok so what is the wall made of? You could drill through, and afterwards make good, the 6cm pelmet so as to drill into the wall square then fit a rawl plug, or similar then screw in the hook 80mm should be enough room to do that.

Audio, especially the MP3 style stuff has very low bandwidth demand, even the Tidal studio quality is not much more hungry, the latency is the issue and Sonos, other systems EG Naim are available, deals with that anyway so I can't quite see the need to wait for WiFi 6

The 'ideal for double thickness Plaster board' bit gives away the pull through issue you might experience with single layer stuff. 12Kg is probably too much for a single point on a single layer of PB. @Adsibob you are probably going to have to spread the load. When I needed to do this, although my need was only a couple of KG, I cut a slot in the PB slid a piece of plywood in over the place I wanted the load, secured the ply with PB screws from inside the room, fitted the 'hook' and then made good the slot with easyfill.

If you have some airflow through the beads then although you have insulation you don't have air tightness is this unimportant?

Yes but 2% feels like a lot of mW in the case of London, can you get that from a few weirs? It seems there are 7 of them on the thames: https://www.shareable.net/a-people-powered-legacy-community-hydro-on-the-river-thames/.

Wonder what the definition of large format is. 600x600 bigger or smaller?

You can get mortgages on land only, so you could go almost anywhere for that and then pay that off with a self build mortgage when you are ready.

Does not matter who goes first its the after you have gone bit that matters and is a real challenge - documentation obviously helps. For those creating code you don't just need to maintain the target device but also the development environment, which is increasingly difficult given the continual need to move it from one PC to the next or keep a special PC with it on just in case.

What about looking at a monthly pattern (well it is close), did it also happen on the 6th December but you not notice it, or could it be the router leases timing out / not renewing somehow - there seems to be quite a a bit, no pun intended, on this on the RPi forums.

I am no architect so please take my thinking with a pinch of salt. It does look a bit 'complicated'. Cannot see why you need the two doors in the corridor to the kitchen, (lounge exit - which would create more functional space in the lounge if removed & kitchen entrance - which adds nothing other than complexity in my view) - many like open plan living and no doors are a hint at that and would allow a view from the Lounge to the garden. The kitchen does feel 'pinched' there is no seating / dinning area there so not sure where you intend to put yourselves for eating - unless the run beside the dishwasher is a bar of some sort. So, overall, I think making the extension longer is a big plus.

And half a wind farm in a force 8 gale to get it to full brightness?

Wonder what the trick is to sound proofing them? We have one on our Utility, not yet fitted so I could change it.

Welcome to THE forum for people like us.

Farnell have been doing this for some time, they call it a handling charge - I save up my orders.