How Can I Tell If My Chimney Needs Cleaning?

Proper chimney maintenance is critical for the safety and general upkeep of a home. While general guidelines exist for cleaning frequency, certain chimneys will require more regular cleanings based on the frequency of chimney use and the types of wood burned. You can determine the maintenance needs of your own chimney with a few considerations.

Check for Creosote

Creosote can form along the inner surface of your chimney when wood fails to burn completely. If creosote accumulates, your chimney will require cleaning. To check for creosote, open windows nearby (to increase the air circulation and prevent downdraft from the chimney) and put on a pair of protective goggles and a dust mask. Reach your fireplace poker into the fireplace and scratch the surface directly above the damper (the metallic smoke chamber). If your poker scratches a paper thin groove, you don't need cleaning. If the scratch appears more than 1/8 inch thick, you need a cleaning.

Smell the Odor

Strong chimney odor is an indication of excessive creosote buildup. Odor becomes most prevalent in humid weather (particularly in the summer months). If you want to check for excessive creosote odor, turn on your air conditioner and smell the scent within the fireplace. If you notice an unpleasant stench, contact a chimney cleaning specialist.

Last Cleaning Date

The National Fire Protection Association advises that you have your chimney inspected and cleaned at least once per year. If you frequently use your fireplace, you may require additional cleanings (once at the beginning of wood-burning season, and once at the end), but strive for at least one cleaning per year. Chimneys were responsible for 1,040 reported injuries in 2006, according to the NFPA, so don't take your chimney maintenance lightly. If more than a year has passed since your last cleaning, contact a specialist right away.

Amount of Wood Burned

If you use your fireplace frequently or even daily, your cleaning needs will surpass those of the average household. Chimney expert Clay Lamb, president of American Chimney and Masonry, recommends cleaning your chimney after every cord of wood burned. A cord amounts to 128 cubic feet of wood (4 feet high by 4 feet wide by 8 feet long).

References

• National Fire Protection Association; Home Fires Involving Heating Equipment; John R. Hall, Jr.; January 2009
• Ask the Chimney Sweep; Chimney Cleaning Frequency; Clay Lamb; March 2010
• Chimney Safety Institute of America: Frequently Asked Questions
• "The Family Handyman": When to Clean a Chimney Flue