Plasterboard screws with wide head

[Possom]

The ceiling plaster in my house is plastered over lathes (1930s).

There is a ~4ft long break in the plaster due to, it appears, someone before I owned my home having moved a heavy water tank in the loft which formed the crack.

This means that one section of plaster along the break hangs a few mm lower.

I was wondering if I could possibly attach some plasterboard screws with wide heads through it into the joists above, then just fill in the joint along the crack.

I tried to screw in a standard 8mm diameter plasterboard screw, though the plaster was not held by this. The screw was just going into the plaster, without supporting it.

Perhaps there is a plasterboard screw with a wide head for this situation? Thanks.

 

[Doggit]

It's more than possible that the whole section has been pushed down, so platerboard screws won't push things back up. You might be able to push it back up with an acrow, and a couple of short scaffolding boards to spread the load, on both ceiling and floor. Unless you're happy with a bit of a fudge, I suspect you'll end up overboarding the ceiling with plasterboard, and then skimming it I'm afraid.

Put a piece of wood across the joists in the loft, and see if you can detect a drop where the crack is.

 

[Possom]

It's more than possible that the whole section has been pushed down, so platerboard screws won't push things back up. You might be able to push it back up with an acrow, and a couple of short scaffolding boards to spread the load, on both ceiling and floor. Unless you're happy with a bit of a fudge, I suspect you'll end up overboarding the ceiling with plasterboard, and then skimming it I'm afraid.

Put a piece of wood across the joists in the loft, and see if you can detect a drop where the crack is.

Cheers, thanks very much Doggit.