The Facts: Chimney Fires Fireplace and chimney fires can vary in size and severity — ranging from several hundred thousand dollars in losses when a single room is damaged to a multi-million dollar, total burn down of a home. During the three-year period from 2009-2011, each year on average:
- 24,300 chimney fires started
- 23 lives were lost
- 93 people were injured
- $115.9 million in overall property damage occured
Fireplace and chimney fires typically erupt for two main reasons: improper construction and lack of regular annual maintenance.
The Fiction: Masonry Chimneys Are Indestructible Most chimneys in residential family homes today are of two types: masonry or factory built. Masonry chimneys are built on site of hand laid bricks, and have been the standard fireplace construction for hundreds of years. Many homeowners mistakenly think this masonry is indestructible, but in fact, it can be damaged by extreme weather, lightening strikes, or shifts in the earth, as well as general age deterioration. Factory-built chimneys are more popular in new construction because of the lower material and installation costs. However, they do not last as long as a masonry fireplace — generally 25 to 40 years depending on the amount of use and geographic location.
The Ignition: Deposit Build-Up Even with proper construction of a chimney, maintaining it through annual inspection and cleaning is critical. The buildup of chimney deposits — especially in cold winter when you may be building more fires and keeping them lit longer — is a major factor in chimney fire ignition. Creosote, in particular, is highly combustible as these crusty, tar-like and often hardened deposits can ignite when the internal flue temperature becomes very high.
The Prevention: Annual Chimney Inspection and Cleaning The National Fire Protection Agency (NFPA) recommends that chimneys be inspected at least once a year and cleaned as necessary. It’s important to recognize that the inspection and cleaning of a chimney is a specialized job, and should not be performed by a general maintenance company or handyman. “A chimney and flue system is a complicated mechanical system that requires regular inspections, just as HVAC systems, plumbing systems, and electrical systems do,” says Matt Hunter, Loss Prevention Leader for Fireman’s Fund Insurance Company. “The only way to know if you have a problem with your chimney is to have it inspected regularly.” The Chimney Safety Institute of America (csia.org) is a network of 1,400 Certified Chimney Sweeps in North America. The group has committed to an additional 48 credits of continuing education every three years, so they are current with the latest techniques to diagnose proper draft and flow, and spot potential fire dangers.
The Winter Ahead: Tips to Prevent a Chimney Fire The winter of 2013-2014 was one for the record books in many parts of the country, and the upcoming 2014-15 winter is predicted to have the same extreme cold and moisture. This winter weather will put undue strain on chimneys, whether they are 100-year-old masonry or new factory-built. That’s because homeowners will be building more fires, and burning them longer. Hunter explains, “Fireman’s Fund has partnered with the CSIA to help raise the level of awareness of the need for regular chimney inspections and maintenance. This is especially timely as temperatures begin to drop across the country.” Here are some tips from the CSIA to make your winter fire burning a safe season:
- Burn only seasoned wood, as your fireplace will burn cleaner and avoid creosote build-up that can lead to a fire.
- Be sure not to overload the firebox — stack logs only up to half the height of the opening, and flames should never reach up into the chimney.
- Your fireplace is not an incinerator, so do not burn wrapping paper or boxes as those materials can contribute to flue build-up.
- Build smaller fires using hotter burning woods (hickory and ash) so they burn more completely and leave less deposits.
- Keep an inch of ash on the bottom of the firebox — this allows the coals to nestle down and cool off at the end of the burn.
- Factory built fireplaces are designed with a thinner sheet metal, and may not be able to withstand an all-day fire in them. On very cold days, consider building a fire intermittently throughout the day.
- Be sure the fire burns down before going to bed; and close the fireplace doors tightly.
- Avoid putting expensive artwork, precious family photos, or other collectibles on the mantle, hanging above or on adjacent bookshelves.
Copyright Fireman’s Fund 2014
*“2009–2011 Residential Fire Loss Estimates”, U.S. Consumer Product Safety Commission, July 2013