@Orionaut how did you find removing the lathe and plaster ceiling? We need to do this with the bathroom in the future, wondering how long it takes.
It is hard work and
very very messy. Lots of dust and it gets
everywhere. The dust doesn't just come from the plaster but also the accumulation of other crap (Dead spiders, mouse nests, muck that has fallen thorough the floor boards above etc over the previous 100 years or so) It doesn't take long to pull the lath down but It will take quite a long time to clean up afterwards so it is best to do it all in one go so you only have to do this once.
You also generate far more debris than you might expect, While I cannot comment on your ceiling, the plaster on mine varied from 2-3cm thick over an area of around 12-15 square meters. Make sure that you have a load of rubble bags for packing up the rubbish afterwards.
Are you intending to do this in an "Empty" bathroom or are you going to have to work around installed fittings? (Working around installed baths/showers/units would be awkward. Dust sheets will not be sufficient to protect them. I would actually get some cheap ply and box in anything that could not be removed
You will need gloves, a well fitting face mask (Not the little paper ones, they don't work very well), eye protection (The lath is quite springy and can flick plaster into your face) and thick soled foot ware (The Lath has little nails in it and you will end up stepping on them)
I did it in stages, pulling it down until the dust was too thick to see, letting it settle, and then going in to renew the attack. Be careful cleaning the eye protection. since the dust is quite abrasive and if you just wipe the glasses they will get badly scratched very quickly. (Same also applies when tidying up generally afterwards with any plastic surface)
You will need to take care of any wiring or plumbing that might be in the ceiling space, you do not want to risk damaging it.
If you used something like a scorpion saw
https://www.amazon.co.uk/BLACK-DECK...81ZP43YE79A&psc=1&refRID=N3HCZBXSQ81ZP43YE79A then you might be able to make it a bit less messy by cutting it down in sections rather thasn just pulling it down as I did, but it would take a lot longer and it would still be messy.
If I was going to do it again, I would get dust sheets throughout the house (I do mean everywhere) and tape some plastic sheeting over the door to the room that I could lift to get through, it would reduce the spread of dust throughout the house but not stop it. It would still be messy.
Unfortunately, acquiring such materials is not easy at the moment which is why I didn't do it. But in hindsight it is strongly recommended.
If you have other family (Especially children, older relatives) living in the house, it might even be worth putting them in a B&B for a couple of days until you have tidied up.