Ripping ceiling down

[Northy1]

Hi,
We live in a victorian mid-terrace. The original plaster in the living was cracking, a bit actually fell off.

We contacted a plastered who boarded over it and plastered, screwing into the joists.

The ceiling has since begun to sag over the window. I'm concerned about it dropping on our head and the extra weight on the joists. I want to rip it down but don't know where to start. Wouldn't ripping at it pull on the screws on the joists? Is there a specific technique someone could recommend?

Thanks in advance,,

Tom

 

[HERTS P&D]

Prop it back up again and then re-screw into the joists.

Andy

 

[Gossamer]

Probably didnt use long enough screws. I use 70's for overboarding. Maybe they used shorter ones and / or hit a dud area of joist.
I'd be tempted to get them back, assuming its a recent job, they may well want the opportunity to sort it out.