A chimney that looks fine from the living room can still be hiding a cracked flue liner, a damaged cap, or a dangerous buildup of creosote. Both the National Fire Protection Association and the Chimney Safety Institute of America recommend an inspection every year, regardless of how often you actually use the fireplace.
The three inspection levels
Not every chimney inspection is the same. There are three recognized levels, and which one you need depends on your situation.
- Level 1: The routine annual check. A technician examines the accessible parts of the system, the firebox, the damper, and the readily visible flue, looking for obvious damage or buildup. This is what most homeowners get every year when nothing unusual has changed.
- Level 2: A more thorough evaluation that includes a video scan of the flue lining, plus a look at accessible parts of the exterior, attic, crawl space, and basement. This level is called for when you change fuel type, add a stove insert or reline the chimney, after a chimney fire or malfunction, after severe weather or an earthquake, and notably, upon the sale or transfer of a property.
- Level 3: The most invasive option, sometimes involving removing sections of masonry or cutting into walls to reach hidden problem areas. This is only used when a Level 1 or Level 2 inspection turns up something that needs a closer look to confirm the chimney is safe to use.
What a technician checks
- The firebox and damper, checking brick condition and smooth damper operation
- The flue liner, looking for vertical cracking, gaps, or deterioration
- Creosote buildup and thickness
- The crown and cap, checking for cracks or damage
- Exterior masonry, brick condition, and mortar integrity
- Flashing where the chimney meets the roof, checking for gaps or corrosion
When a cleaning is needed
A dirty chimney can't be properly inspected, so cleaning often comes before or alongside an inspection. Signs it's time:
- Creosote buildup thicker than 1/8 inch, which is considered a fire hazard
- A strong, smoky smell even when the fireplace isn't in use
- Smoke drifting into the room instead of up the flue
- White staining on the exterior brick (a sign of moisture getting into the masonry)
- Crumbling or missing mortar
- A damaged or missing chimney cap
If you notice any of these, it's worth having a certified chimney sweep take a look before you light another fire.
If you're buying or selling a home with a fireplace
A Level 2 inspection is standard practice at the point of sale, and for good reason: it's the level thorough enough to catch a hidden crack in the flue liner or damage that wouldn't show up in a routine annual check. If you're under contract on a home with a fireplace, ask whether a chimney inspection is part of the process, it's a small step that can save a real headache later.
