water on ceiling causes 21

https://thehowtellifitsroofleakscope.fotosdefrases.com/how-to-tell-if-it-s-a-roof-leak-or-something-else-on-your-ceiling

A wet patch on the ceiling usually means trouble—could be a leaky roof after heavy rain, a burst pipe in the floor above, or condensation from poor insulation. If it's actively dripping or bubbling, act fast before the drywall sags or stains spread. Structural rot and mold join in if you let it sit, so grab a bucket and a fan for now, but call a pro to trace the source before it becomes a costly headache.