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5 Causes of Chimney Odors

5 Causes of Chimney Odors champion chimneys

Let’s look at some of the most common sources of bad chimney odors.

Burning wood isn’t the only odor that comes from your fireplace. Chimneys can have all sorts of issues with them, often resulting from an internal blockage. This blockage can come in many different forms – if you have a terrible smell flowing through your home, you may need to take the time to clean it out properly. Let’s look at some of the most common sources of bad chimney smells.

Leaves, Branches, and Other Debris

Have you noticed a smell of rot or decomposition coming out of your chimney? Then, you may have leaves, moss, branches, and other things stuck up there. A pile of leaves can accumulate on the top of the chimney and create a blockage – making it smelly as it rots and dangerous as it can start a fire. Even a few branches or leaves can be a problem if your chimney is flooded with soot. That is why it is important to have a chimney cap properly installed.

Creosote Buildup

One of the leading causes of chimney odors is creosote accumulation. Creosote is a byproduct of burning wood and starts as a flaky powder that sticks to the chimney’s interior walls. As it accumulates, it becomes a thick tar-like substance. It’s highly flammable at this stage and the source of the strong, smoky odor you smell, especially during heavy rain or high humidity.

Moisture Issues

Moisture can enter the chimney through cracks or if you don’t have a chimney cap. Dampness leads to musty odors and mold growth, worsening the smell. Moreover, breathing mold spores can increase allergic reactions and breathing difficulties. 

Negative Air Pressure

Another way odors can easily enter the home through a fireplace is negative air pressure in the house. This problem occurs most frequently during the summer after making home improvements, such as updating the venting system or installing a new roof, windows, or kitchen exhaust fan. When your home is sealed too tightly, even mild odors escape into the home instead of up the chimney.


Birds are the most common animal found in chimneys, and they often cause some of the biggest problems for homeowners as they are known for building nests that create blockages and fire hazards. Many birds can carry diseases, making removal of them dangerous or even deadly. To make matters worse, the removal of many bird species is illegal, making it particularly difficult to address this issue. Other animals often found inside chimneys include bats, squirrels, and raccoons. These animals can carry diseases like rabies or roundworm, while also potentially causing home damage if they make their way inside.

Schedule Your Chimney Cleaning from Champion Chimneys, Inc.

When you need a trusted company for your chimney inspection and chimney cleaning, you can trust our team. Champion Chimneys, Inc. is a fully licensed, bonded, and insured chimney service company that has served customers in Baltimore County, Howard County, and Anne Arundel County, Maryland, since 2001. Our team is trained and certified by Certified Chimney Professionals, Inc. (CCP, Inc.). We specialize in all aspects of your chimney system. Whether you need chimney and flue cleaning service or a full chimney rebuild or inspection, contact us at 443-Chimney today and let us fix all your chimney problems. Also, follow us on Facebook, Twitter, LinkedIn, and Pinterest.

This entry was posted on Friday, February 2nd, 2024 at 11:04 am. Both comments and pings are currently closed.