(615) 459-2546 office@ashbusters.net

Chimney Structural Anatomy Image - Nashville TN - Ashbusters ChimneyOne of the most common questions we get asked about chimneys at Ashbusters has to do with the anatomy of a chimney. For a chimney to work safely and properly, there are several crucial components that need to be in good condition. Which parts of the chimney are the most essential? We would like to answer this question by telling you about these components of a safe and efficient chimney system.


Many people confuse the flue with the chimney itself, but a chimney can have multiple flues. Each appliance that is connected to a chimney should have its own separate flue. This means your fireplace, furnace, and wood stove can all be connected to the same chimney. However, this is only true for masonry chimneys. According to Chimneys.com, a factory built chimney can contain only one passageway for venting combustion byproducts.

Flue Liners

For each heating appliance to work efficiently and safely, its flue should be lined with a clay tile, stainless steel, or cast-in-place liner. A flue liner is necessary for three reasons: to protect your home from heat transfer, to keep the masonry materials safe from corrosive byproducts of combustion, and to provide a correctly matched size to the heating appliance.

Chimney Crown

At the top of a masonry chimney, there should be a chimney crown to keep water from rain and melted ice and snow out of the chimney. The construction of the chimney crown is important and should be gently sloped towards the edge to allow water to run off the crown. The flue liners should also extend above the crown at least two inches. Ashbusters also recommends having a chimney cap professionally installed at the top of the chimney to provide even more protection against water penetration.

Cleanout Door

The small metal cleanout door at the bottom of each flue is there to allow chimney professionals to easily remove soot and debris. However, fireplaces typically do not need a cleanout door as the debris from soot and creosote can be removed through the fireplace opening. You may have a door underneath your fireplace. This is most likely the ash pit door, which allows you to easily clean out ashes and ash residue.

Making sure each of these chimney components work properly is an important part of a chimney inspection from Ashbusters. We look closely at each part to ensure there are no problems that could cause your chimney to not work safely or efficiently. Contact us today to schedule your annual professional chimney sweeping and inspection so that you can enjoy safe and warm fires all winter long.