Ceiling replacement

Buford T Justice

Ceiling in the Sitting room is complete pants, and it needs a new one. I'm not going to go through the hassle of pulling down what's there (ugh) but I was wondering, do I need to put up batons for the new slab that's going in or can I slab directly over what's there, knowing where the Joists are and fixing through the old slab into them?

Any reason I shouldn't do that?

Lumen

There may be electrics and or pipes where you put through the fixings.

Buford T Justice

I know where they all are - easy to avoid

alan1963

Hi this is the sort of work i do all the time here in Yorkshire,if its a old lathe and plaster ceiling and some of the old plaster has parted from the lathes,sagging down, then this has to be cut out and replaced with plaster boards before underboarding the whole ceiling, you obviously still have to cut boards to join on the centre of joists,screw boards up with 50mm or so driwall screws about 150 mm apart along all the joists, makes a good solid job and saves a lot of muck.

Buford T Justice

alan1963 wrote: »

Hi this is the sort of work i do all the time here in Yorkshire,if its a old lathe and plaster ceiling and some of the old plaster has parted from the lathes,sagging down, then this has to be cut out and replaced with plaster boards before underboarding the whole ceiling, you obviously still have to cut boards to join on the centre of joists,screw boards up with 50mm or so driwall screws about 150 mm apart along all the joists, makes a good solid job and saves a lot of muck.

No, its a simple 12mm slab ceiling and I want to re-slab over the existing.

alan1963

Hi
if the ceiling is already plasterboard then it is perfectly possible and easy to underboard it, however this is some thing I have never been required to do as,well it is see as a waste of money. I would nomally just cut out and replace any really bad areas(from leaks etc) then paint the whole ceiling with PVA glue and then when it is dry just re-skim the whole thing.

Buford T Justice

Its too much work to fill tbh. The edges are ruined from coving that was there years ago, and it has many holes from downlighters that were there plus an old ceiling rose. I wouldn't be skilled enough to skim an entire ceiling (long story there) but I'm a dab hand at the aul joint & taping.

I don't think it'd be that easy to get a plasterer for such a simple job either.

tonydude

No reason why you can't, figure out how the existing slabs were fitting and stagger the new slabs from that to create an overlap. Ensure the screws you use will get a good bite into the ceiling joists and watch for electrics.

DublinDilbert

Re board it with 9mm slab (not foil backed), find and mark all the existing joist locations so you can join the end of each slab over a joist. Any slabs i've seen/used are metric in one direction and imperial in the other. This might seem like a small difference, but if your run them the wrong way after a slab or two the join will no longer be on a joist. It also depends on when the house was built if the joists are spaced to metric or imperial.

But when its done its a great job, also the plaster will love you as hey like to skim a fresh board. Before doing any work i'd take a straight edge / spirit level and find any bellys in the existing ceiling and remove them, before putting up the new board.

The added bonus is that it improves sound proofing and stops heat rising as fast up to the next floor.

decky1

alan1963 wrote: »

Hi
if the ceiling is already plasterboard then it is perfectly possible and easy to underboard it, however this is some thing I have never been required to do as,well it is see as a waste of money. I would nomally just cut out and replace any really bad areas(from leaks etc) then paint the whole ceiling with PVA glue and then when it is dry just re-skim the whole thing.

Try Thistle bond instead of PVA much better and a bit of grit in it to help grip new plaster.;)

Bullocks

Buford T Justice wrote: »

Its too much work to fill tbh. The edges are ruined from coving that was there years ago, and it has many holes from downlighters that were there plus an old ceiling rose. I wouldn't be skilled enough to skim an entire ceiling (long story there) but I'm a dab hand at the aul joint & taping.

I don't think it'd be that easy to get a plasterer for such a simple job either.

Slabbing it should be no bother to you. Will you have help? Either way a dead man is very handy to help keep the slab up while you're screwing. Usually a 38/42mm screw will be good enough and use plenty. Just check the old ceiling for thickness and allow for the closest screw that will go 20mm into the joists.
Make sure to scrape every little bit off the old ceiling before you start slabbing because it doesn't take much to put a bulge in the new slabs and throw you off.
Uni bond all around the edges of where the wall meets the ceiling to avoid cracking after you have it taped. You could tape onto the wall if you wanted to cover the joint either with corner tape.
Cover everything with plastic (not ould stuff off the silage pit haha). It's a lot easier at the end to pull it all up rather than hoovering dust for a fortnight

Buford T Justice

Ended up with batons inline with the joists above in the end. They weren't running 16 inches apart evenly, so the batons gave the extra leeway. Joint and taping done now. Just need to paint.