Chimney sweeping needs to be performed when the smoke from burning wood cools and forms a resin inside the fire burning system. This resin is called creosote, and is the build-up on the inside walls of the fireplace and the chimney flue. Think of the smoke-like water vapor traveling through a pipe. At first it is hot and steamy. Then as it travels through the pipe, it cools and forms water droplets on the inside walls. The same happens with the smoke that comes from the wood you burn, only as it cools it is like sticky tar that can dry to a granular, rocky, or flaky substance on the inside walls of your chimney.
Chimney sweeping is performed when the build-up is one eighth inch or more. If left unattended, more build-up could lead to a blockage. If you have any concerns or questions about the condition of your chimney you should call a certified chimney sweep to inspect it.
RMR Chimney Sweep
2150 Touhy Avenue
Elk Grove Village, IL. 60007