Creosote & Chimney Fires: What You Must Know
A chimney fire can be devasting if the fire spreads and engulfs your home. Even when the fire is contained to the chimney, it can cause severe damage to the flue lining and chimney exterior. Every year, more than 25,000 homes in the U.S. suffer a chimney fire. The total cost of these fires is over $125 million in property damage. The leading cause of chimney fires is creosote.
What is Creosote
When you burn wood in a fireplace or stove, it produces combustion by-products. Those by-products include water vapor, smoke, gases, tar fog, unburned wood particles, and hydrocarbon. When they condense in your chimney, the result is creosote.
Creosote is an extremely flammable chemical compound made up of combustion by-products. It can be black or brown. In the early stage, it is crusty and flaky. As it builds up, it becomes sticky and tar-like. Eventually, it will harden and look shiny. All three stages are highly combustible. A stray spark or high temperatures in the flue can ignite creosote deposits.
Chimney fires caused by creosote can burn for long periods of time at extremely high temperatures. While some chimney fires are loud and noticeable, others are quiet and go unnoticed the damaged is discovered during an inspection. A quiet chimney fire can be just as destructive as a loud one. Using your fireplace after a chimney fire, even if you don’t realize you’ve had one, increases the risk of a house fire and of carbon monoxide poisoning.
How to Prevent a Chimney Fire
Most chimney fires are preventable. The best way to prevent a chimney fire is by taking these two steps.
1. Reduce creosote build-up.
You can minimize the amount of creosote in your chimney by employing clean burning techniques. Using clean burning techniques reduces the number of combustion by-products produced by your fire. Fewer combustion by-products results in less creosote. Clean burning techniques to follow include:
- Only using safe, natural fire starters like pinecones, dried twigs and old newspapers. Never cardboard or magazine paper (both contain chemicals that emit toxic gases when burned) or liquid fire starters.
- Always burning seasoned hardwood that has less than a 20% moisture content.
- Making sure the damper is fully open when the fire is going so that there is enough airflow to feed the fire oxygen.
- Horizontally layering seasoned logs, with space in between, to produce a hot, long burning fire.
2. Schedule an annual chimney cleaning and inspection.
Even a small amount of creosote can cause a fire. That is why both the National Fire Protection Association and Chimney Safety Institute of America (CSIA) recommend an annual chimney cleaning and inspection. Having your chimney cleaned and inspected once a year has been proven to reduce the risk of a chimney fire and prevent the risk of carbon monoxide exposure and poisoning. During the inspection, a CSIA-certified chimney sweep will look for signs of damage or disrepair that could cause a fire or allow carbon monoxide into your home. They will give you a full report at the end of the inspection with recommendations for next steps if they uncover risks.
Ensuring the safety of your chimney is the top priority of professional chimney sweeps and technicians like us. Every year, we invest in CSIA training and certification to ensure we can provide you with the best chimney services. If your chimney needs cleaned or inspected, contact us today!