Protect people and belongings
Stay away from sagging ceilings and wet electrical fixtures. Move possessions and collect dripping water only when that can be done safely. Describe the active leak when you request help.

Water inside the building can start at a shingle, flashing joint, pipe boot or low-slope roof detail. The repair needs to find where water enters, even when that point is away from the stain.
Water follows surfaces before it drips. It can move beneath shingles, along underlayment or down framing, then appear in a room some distance from the entry. Wind-driven rain can also reach a gap that stays dry in ordinary rain.
Leak tracing considers those paths and the condition of the assembly. A wet room location is useful context, but repairing only the spot directly above it can leave the actual opening untouched.

The failed piece needs to be reconnected to the layers around it. A replacement boot, flashing repair or shingle patch should restore the water path, not simply cover the symptom.
When the roof is opened, wet or weakened decking can change the amount of work. Interior drying, insulation or ceiling restoration may involve separate trades after the roof entry is addressed.
A split boot or loose connection lets water follow the pipe or opening into the assembly.
Step and counterflashing direct water back onto the roof. Gaps or poorly connected lower ends can send it behind the covering.
A torn or displaced shingle exposes what lies below. The surrounding material must be sound enough to receive the repair.
Active water entry and the permanent roof repair are connected but different jobs.
Stay away from sagging ceilings and wet electrical fixtures. Move possessions and collect dripping water only when that can be done safely. Describe the active leak when you request help.
Temporary protection can limit more water entry while conditions or materials are resolved. The lasting repair still needs compatible materials and a sound connection to the roof layers.
Tell us what you have noticed and where the property is. A free roof inspection helps put the next decision in focus.