What is creosote, and how does it form?
Creosote is the byproduct of the incomplete combustion of wood. It first starts as a gas mixed in with the smoke. It comes into contact with the chimney flue and condenses as a liquid. When it cools to below 250° F it solidifies and becomes the creosote that the chimney sweep brushes out. A lot of things can increase the build up of creosote. If you don’t have sufficient draft in your chimney the smoke will linger in it. If you have a fire that is smoldering, this creates a lot of smoke. Soft woods that are not properly seasoned can add to the buildup.
