Do this now
- Put a bucket under the drip and move furniture and electronics.
- If the ceiling is bulging, pierce the lowest point with a screwdriver so it drains into the bucket instead of collapsing.
- Turn off power to a light fixture or outlet that water is reaching.
- If it is safe, look in the attic with a flashlight to see where water is coming in and place a container there.
- Stay off a wet roof. Call a roofer for a temporary patch or tarp, and photograph the damage.
What usually causes it
- Cracked rubber boots around plumbing vent pipes
- Failed flashing at chimneys, skylights, walls and valleys
- Missing, cracked or lifted shingles
- Nails backing out of the deck
- Ice dams in winter or clogged gutters backing water under the edge
What a professional will do
A roofer traces the leak from the attic and the roof surface, often uphill from the stain, and repairs the actual entry point — usually flashing or a penetration — rather than coating it with sealant. They should show you photos of what they found and tell you whether the rest of the roof has useful life left.
How to prevent it
- Have flashing and pipe boots checked every few years
- Keep gutters and valleys clear
- Trim branches that touch or overhang the roof
- Look in the attic after heavy rain
Rules and paperwork in Pennsylvania
- Pennsylvania’s Home Improvement Consumer Protection Act requires most contractors who perform home improvements to register with the Attorney General’s office and to give you a written contract for any job over $500. The registration number belongs on the estimate and the contract — ask for it.
- Pennsylvania does not issue a statewide license for this trade. Some municipalities register or license it locally, which is one reason to confirm requirements with your own municipality.
Sources: Pennsylvania Office of Attorney General — Home Improvement Consumer Protection Act; Pennsylvania Department of Labor & Industry. Rules change — confirm current requirements with the agency and with your municipality.
Frequently asked questions
Why does my roof only leak in heavy or wind-driven rain?
That pattern usually points to flashing or a wall intersection rather than the shingles themselves. Tell the roofer the conditions when it leaks.
Can a leak be repaired, or do I need a new roof?
A single leak at a boot, chimney or valley is usually a repair. Leaks in several places on an old roof point to replacement.
How soon will a ceiling stain turn into mold?
Wet materials can grow mold within a day or two. Dry the area quickly and find the source rather than painting over the stain.
Go deeper
Our full roofing guide covers how the work is done, what affects the price, and what to ask before you hire, and there is more on roof repair.
Related problems
This guide is general information, not a substitute for a professional assessing your home. If you are unsure whether something is safe, treat it as if it is not.