Q. I just purchased a home that has a wood-burning fireplace. I was told to have the chimney inspected before building a fire. I'll probably only use the fireplace for aesthetics. Are there any other precautions I should take so I can safely use the fireplace?
A. Depending on the type of wood the previous owners used, the flue could be clogged with creosote, an oily substance that clings to the walls of the flue. Over time a heavy buildup of creosote can be ignited, and the resulting chimney fire can damage the tile liners. Another problem is that the creosote can seep into cracks or voids between the flue liner and the bricks of the chimney itself. If the creosote is ignited by a chimney fire, the fire can spread to the wood frame of the home or the home's attic.
It is very important to have the flue liner cleaned and inspected once a year. If you have a wood-burning stove attached to the chimney, the flue needs to be cleaned and inspected twice a year. According to data obtained from the U.S. Consumer Product Safety Commission, the No. 1 cause of residential fires is either the chimney, the fireplace or a chimney connector.
Estimates of residential fires associated with the chimney:
• 26,400 in 2006
• 27,000 in 2007
• 27,200 in 2008
Select a chimney sweep that is certified by either the National Chimney Sweep Guild, www.ncsg.org, or the Chimney Safety Institute of America, www.csia.org.
In addition to having the flue cleaned and inspected, make sure the sweep inspects the chimney crown or wash (the top flat part of the chimney) and seals any cracks to prevent water intrusion. He or she should also check the firebricks inside the firebox and tuck-point, a process where the cracks between the bricks are sealed, using a refractory fire clay. Never use brick mortar inside a firebox. The damper should be easily operable, and doors and screens should also be inspected to make sure they close properly.
If the chimney does not have a cap on the flue, add one to prevent hot embers from escaping to neighboring homes and to keep birds and animals out of the flue. When removing hot ashes, use a fireproof container and store the hot embers outside and away from the home until they can be safely discarded. To slow the process of creosote buildup, use only hard woods or commercial, factory-made logs for burning.
• Dwight Barnett is a certified master inspector with the American Society of Home Inspectors. Write to him with home improvement questions at d.Barnett@insightbb.com.
Scripps Howard News Service