How often should a chimney be cleaned

The annual rule

Once a year for a wood-burning fireplace or stove that gets used. The National Fire Protection Association's standard is an annual inspection regardless of use, and a sweep whenever creosote reaches a level that needs it.

When to go more often

Heavy use, wet wood, a cool flue, or a wood stove that runs all winter builds creosote faster. In this county a winter-burning stove can justify twice a year.

When less is fine

A gas fireplace or an unused flue does not build creosote, but the inspection is still worth keeping annual because caps rust, liners separate, and animals move in.