As summer approaches, you may have started to notice a smell coming from your chimney. Humid, summer days combined with moisture is a good recipe for undesirable odors coming from your fireplace and chimney. This smell is probably not new for homeowners, but it does not have to be something you continue to live with.

There are a few reasons you may be getting a funk from your fireplace and chimney. The cause of which can be discovered during a professional chimney inspection and cleaning.


Creosote Buildup

A common cause of chimney odors is creosote: a natural byproduct of burning wood. If allowed to remain inside the chimney, it could become absorbed into the porous, masonry construction causing the smell to become locked below the masonry’s surface. A chimney sweep can clean the creosote from the masonry, but this will not remove the absorbed smell.

Air Pressure

The real cause of the smell entering your home is air pressure. As air moves down your chimney, it causes all of the smells lingering within to come inside your home. Negative air pressure can be caused by any of the following.

  • Inefficient Damper Closures
  • New Furnace, Boiler, and/or Water Heater
  • New Windows and/or Doors
  • Home Additions
  • Change in Roofing Ventilation
  • Stove Range Exhaust Fans
  • Dryer Vent Exhausts
  • Neighboring Structure’s Height Increase
  • Central Vacuum
  • Additional Chimneys

A quick and simple solution to a negative air flow situation is to crack a window every once in a while. This will cause the negative air pressure to come from this outlet instead of the chimney. Also, close the damper anytime the chimney is not in use to seal off the problem.


Moisture causes plenty of problems for chimneys. One of those being a musty smell if the chimney is not properly sealed off from water exposure. By installing a top mounted damper or chimney cap, you can prevent further water from leaking into your chimney.

Other Causes

Unfortunately, the smells from your chimney can be a lot worse. If leaves are allowed to enter your chimney and decompose, this could lead to a rotting smell. Animals are also known to enter chimneys, and they can leave feces inside it or worse their dead bodies – neither of these smells are pleasant.

Fortunately, both of these problems can be easily solved by installing a chimney cap. This will keep leaves out and will prevent animals from getting trapped inside.

Resources: Sweepy Stories, Superior Chimney

Read for More Information:
Four Common Problems That Require a Chimney Sweep
Is Your Firewood Seasoned?
Cleaning Creosote from Your Chimney

Wells & Sons Chimney Service offers a full range of chimney cleaning and repair services to the Chester County, Berks County, and Montgomery County, PA areas including the cities of Allentown, Pottstown, Perkasie, Schwenksville, Exton, Phoenixville, Norristown, and Gilbertsville. Chimney cleaning services include levels 1 thru 3 chimney inspections, and chimney sweeps using a high-velocity ROVAC vacuum.