We live in a house built in 1920. The ceiling in my sons room is still the original plaster and lath – or was, until approximately 1/5 fell down without warning.

We have had a couple of quotes from plasterers and both are recommending addressing the issue by boarding on top of the original ceiling – rather than taking the original down and starting again.

I’m not looking for the cheapest repair, but a long-lasting ceiling with a good finish.  Will their recommended approach do that?

There are others on here more able and capable than me. But, there’s little logic in covering something that is structurally unsound with a new surface.
Speaking as a DIYer as opposed to an expert, it would not be a big job (although it would be messy) to remove the old ceiling and re- board and skim with new plasterboard. If 1/5 has already fallen down, it would be the correct way forward.

I would board over it.

The mess involved in removing a lath and plaster ceiling is incredible.

Its also not guaranteed to separate cleanly from the plaster on the wall.

over boarding is pretty common. for not underestimate the mess of removing a ceiling. you will need to seal the room and wear decent ppe. my tip also charge for plaster waste

Yeah just overboard. So long as it’s screwed through into stable underlying substrate e g joists, what are you worried about? It will save a lot of work.

You might need to think about how to deal with coving. This can be sorted out using beading

Having renovated a Victorian house (including overboarding! It hasn’t caved in yet or even cracked!) I now realise a lot of what makes a cost effective job is avoiding doing work that you don’t need to do.

Same as in may facets of life and work!

I have a 1930s house that I refurbished, I’ve done a bit of both  Boarding over is a good solution, you can take down the old ceiling but all you will gain is more effort and mess aka a bigger bill.

Overboading is fine – they’ll find the joists and screw through into those.

Removing lath and plaster is not at all worth it.

This does of course assume it’s not the underlying joists which are the problem!

assume it’s not the underlying joists which are the problem!

This is a good point. Why has the ceiling come down?

My money is on there having been an “incident” that the son is keeping quiet about;-)

I too have a 1920s house that I’m renovating, and I too have done both.

If you can stand to lose the the height then boarding is the way to go. I’ve just removed the lathe a plaster section of my hallway ceiling (the extension is board only) and it was a horrible job that I wouldn’t have done if boarding wouldn’t have lowered the ceiling enough that I’d hit my head on it going up and down the stairs.

The nails on the original lath are usually quite short with small heads. They also have a tendency to rot/rust so do check there is no water ingress. You obviously need to clean up the fallen area and place a piece of board in the gap as a packer, make sure it is as close to the original depth as possible 9/12/15 mm then overboard fixing to the original ceiling joists.

“The mess involved in removing a lath and plaster ceiling is incredible.”

+1

It’s the worst DIY job I’ve done – the dust gets everywhere and removing the nails from the joists takes *hours* and you can say goodbye to any floor covering however much protection you put over it.

And once you’ve finished you still have to put up the plasterboard and give it a skim.

Having said all that – if the rest of the existing ceiling is in poor shape with blown plaster etc then it may not be flat enough to plasterboard directly onto. In one room I ended up screwing slim battens through the lathe and plaster ceiling to push it back up flat and give a good base for the plasterboard. It was a Victorian house so there’s was enough height to do it.

Thanks all for putting my mind at rest.  I’ll let the preferred plasterer know he can book us in.

My money is on there having been an “incident” that the son is keeping quiet about;-)

Possible but not likely. It had just been painted by some decorators and the day they finished it fell down in the middle of the night.  They deny all liability though…

The mess involved in removing a lath and plaster ceiling is incredible

I have much regret in tearing down all of mine. I honestly swear that the dust, most noticeable in the morning after polishing a pair of shoes the night before, took two years to settle.

https://www.youtube.com/watch?v=wvQb0pTxqN4%5D

Edit: How do you embed a ******** video?! I swear I could do it a few weeks ago.

… It had just been painted by some decorators and the day they finished it fell down in the middle of the night. They deny all liability though…

Rollers used for the ceiling?
Heavy handed use of rollers disturbed the “barely hanging on” ceiling and it later fell.

Not really the fault if the decorators to be fair. Sounds like the straw that bike the camels back really.

boarding over is the way i do it if possible, the existing plaster will probably be much flatter for the boards than the joists. they werent that fussy about how flat the under side was in those days as the lath and plaster would flatten it out.
last time i had to remove a ceiling to get sound insulation in it took a lot of work to get it flat enough for boards.

It had just been painted by some decorators and the day they finished it fell down in the middle of the night.  They deny all liability though…

As above, not really their fault.

Lath and plaster ceilings have a real tendency to hang on by the skin of their teeth and then suddenly let go catastrophically.

I had one collapse  in its entirety whilst i was standing still in the middle of an empty room.

Plaster doesn’t stick to wood so prior to the invention of plasterboard, they relied on squidging the browning coat (basecoat) through the gaps between the lathes; the whole weight of an inch of plaster then hung on these “keys”. It only takes some water ingress of a knock for the keys to break and then the whole thing relies on surface tension or wallpaper to keep the ceiling up.
Actually the lathes are nailed to 1″x1″ timbers called branders and these are nailed to the joists which is why when you’re looking for a joist (to hang a clothes pulley for example) you’ll find they’re sunk 2″ behind the plaster face.
Plasterboard is actually a really smart invention; most folk think it’s shit!

I’d get the lighting updated while the ceiling is a wreck.

As above, not really their fault.

To be fair – I didn’t blame them, just asked if anything seemed wrong with the plaster and they responded by saying that it hadn’t and they hadn’t done anything…