Stay clear, then call
A collapsed ceiling means more weight came down than the fixings could hold. The remaining ceiling next to it has often shifted too. Get everyone, including pets, out of the room. Don't try to push it back up. Call us — we'll get there as fast as we can.
What we do on arrival
Assess the structural state of the surrounding ceiling
Safely remove any further unstable material
Identify the cause — water, weight, fixing failure
Provide a written quote for full replacement
Schedule the replacement as soon as possible
Why we replace rather than reinstall
A ceiling that has come down has failed for a reason — fixings, water, weight, or age. The honest answer is a full new ceiling on properly-spaced framing, not a re-hang of whatever was there before.