What makes creosote

Chimneys expel the by-products of combustion, such as smoke, water vapor, gases, unburned wood particles, hydrocarbons, tar fog and assorted minerals. As those things flow up a chimney, condensation occurs. Creosote is the resulting residue which sticks to chimney walls. The burning of unseasoned wood, which has water trapped in the cells of the logs, can contribute to the buildup of creosote.

Signs of a chimney fire

When there's a fire in a chimney, dense smoke will be emitted and there may also be loud cracking or popping noises. There may also be flames visible from the top of the chimney.

Strangest incident with a chimney fire

Here's a strong indication that something is amiss in your chimney. A homeowner in Chesterfield County, Va., was alerted to his chimney fire by the sudden influx of blazing squirrels into his home via his fireplace. The critters ignited several spot fires inside the house. They'd built a nest inside the chimney, and when the homeowner lit a fire, it also ignited the nest and its inhabitants.

The Chimney Swift

A bird so-named because of its fondness for building nests on the vertical walls of a chimney.

Facts about woodstoves and fireplaces

More than half of Americans use fireplaces and woodstoves. Heating fires account for 36 percent of residential home fires. The top cause is cooking.

Most heating-related fires occur in January between 5-9 pm. Eighty-seven percent of heating-related fires are chimney fires.

Across the United States, there are about 50,000 heating related fires annually, causing 150 deaths, 575 injuries and $326 million in damages.