Water around a chimney needs a source investigation. A stain inside the home does not identify which exterior component has failed.
Updated September 10, 2026
Your home in Pittsburgh.
About 75% of occupied homes in Pittsburgh heat primarily with utility gas. Many chimneys in Pittsburgh therefore vent a gas furnace, boiler, or water heater rather than a wood fire, and those flues still need inspection for liner condition, moisture, and blockage. Fewer than 0.1% of occupied homes in Pittsburgh use wood as their primary heating fuel. Most fireplaces in Pittsburgh see occasional use, and even occasional use calls for an inspection before the heating season. The nearest NOAA climate normals station (Pittsburgh Allegheny Co Airport, about 7 miles from the Pittsburgh city center) averages 5,563 heating degree days per year. That is a substantial heating season, so plan inspections before the first fire and look for new water or masonry changes after winter from a safe position.
What you can observe safely
- Note whether the leak follows rain, snowmelt, or wind.
- Photograph the stain from a dry, safe position.
What to avoid
- Do not climb onto the roof or enter the chimney.
- Do not alter gas components, venting, or safety controls.
- Do not use a test fire to diagnose the problem.
Possible causes to assess
- Roof or flashing connection
- Crown, cap, or masonry condition
- Moisture paths that need tracing
A symptom cannot establish the cause remotely. An assessment of the complete system helps determine the appropriate repair.
Chimney repair in PittsburghA few common questions
Can this be diagnosed from a photo?
A photo can document a symptom and help prepare a visit. It cannot confirm concealed conditions or establish that a chimney or fuel-burning appliance is safe.