What is creosote, and why is it bad for my chimney?

Creosote is a natural byproduct of the combustion of wood.  It starts in the form of smoke and as it rises through your chimney it cools and sticks to the inside of your flue.  If your chimney is not regularly inspected and cleaned, the build-up of this highly flammable and acidic byproduct can cause chimney fires and deterioration of the flue. This will lead to expensive repairs, such as relining or rebuilding your chimney.  Small or smoldering fires leave tar glaze creosote which is very difficult to clean.  This can also lead to certain smells coming from your fireplace which impact your indoor air quality.  Hot fires with dry seasoned hardwood create flaky or powdery creosote that is easily cleaned.