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On a cold winter night, you are enjoying the crackling and warmth of a fire in your wood stove or fireplace.  The last thing that you may be thinking about is the danger of a chimney fire because of a dirty chimney due to creosote buildup.

You may ask- what is creosote?  Creosote is a black or brown substance that lines the interior of a stove pipe and chimney.  It may be a sticky tar like substance, or it could be flaky and crusty.  Creosote is highly flammable, and when this substance becomes hot enough it can combust and now you have a chimney fire.

What causes creosote to form? When a fire is burning in a wood burning heating unit, there are by-products of combustion- the substances produced when wood burns. These substances include smoke, water vapor, gases, unburned wood particles, and assorted minerals. As these substances exit the fire place and cool on the way out of the chimney, the residue that sticks to the inner walls of the chimney is creosote.

How can creosote be reduced?  One major cause of creosote is burning firewood that is “unseasoned” or not dry enough to burn. A rule of thumb is to cut and split your firewood a couple of years before you intend to burn it.  This “drying time” can vary upon the species of wood that you burn, but typically hardwoods such as oak and hickory will require more drying time that a softer species of wood, and hardwoods will have much more in heat value when properly seasoned.  Seasoned wood burns hotter and faster than unseasoned wood, so the smoke and other substances are hotter while exiting the chimney, thus resulting in less buildup of creosote.

Clean your chimney and stove pipes that lead from the unit to the chimney before heating season arrives. Also make sure to clean the damper within the stove pipe also.  If you do not have your own brushes to clean your own chimney, or are not able to climb to the top of the chimney to do so, it is recommended that you call a certified chimney sweep to have this done.  If you burn wood on a daily basis it may be necessary to clean your chimney a couple of times during the winter as well. It is also advisable to have a professional inspect your chimney for cracks on the interior and interior of your chimney annually.  If you have clay liners on the interior of your chimney they typically will not last as long as other liners such as stainless steel. In the case of a damaged chimney you may need to have your chimney relined with a new flue.

Lastly, when you are building a fire in your wood burning unit, never use a combustible fuel as ignition of your fire.   This could result in an explosion, injury, or even a home fire. Also, never store combustible materials near your woodstove or fireplace.  Make certain that your wood stove was properly installed with the correct distances from the wall and ceiling, and that there is a certified fire retardant material on the wall and floor around the wood burning unit.

Don’t wait until it is too late. Have your chimney inspected and use these tips to provide a warm and safe environment in your home, and to prevent damage to your home and serious injury to you and your family.

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