It's probably roof damage, but two other things I've seen are condensation dropping off a saggingAC evaporator line due to the insulation around the line corroding (not sure if you have central air) and a leak on a wax toilet ring due to heavy plunging. It's worth checking what's above the water damage.
MisterSlippers t1_iqvnd7x wrote
Reply to Leaky ceiling, poked a hole in the ceiling with a screwdriver, and after 15 minutes the dripping stopped. What's going on? by UnofficialSlimShady
It's probably roof damage, but two other things I've seen are condensation dropping off a saggingAC evaporator line due to the insulation around the line corroding (not sure if you have central air) and a leak on a wax toilet ring due to heavy plunging. It's worth checking what's above the water damage.