Chimneys, fireplaces, heating appliances and utility flues should be inspected annually by a qualified chimney sweep to assure the system is suitable for continued use and there are no safety hazards present. Chimney inspections are normally done at the time of an annual sweeping service, when a house is sold or when there has been an incident such as storm damage or chimney fire.
Hidden damage inside a chimney can allow heat, smoke and carbon monoxide to leak inside the home, which can be a serious health hazard and fire hazard. Improper clearances to combustibles may allow heat to pyrolize (chemically change) any nearby wood and cause it to ignite without flame, which may result in a house fire.
An accumulation of creosote inside the flue, smoke chamber or chimney pipe can ignite via an errant spark, causing a chimney fire to start. Creosote accumulation should be removed by a trained professional with the proper equipment and dust/soot control.
The fact is, masonry chimneys and manufactured chimneys are more vulnerable to damages than most people think. Lack of a proper chimney cover will allow damaging rain to enter the chimney.
Rain, when mixed with creosote, forms an acid that eats away mortar joints between flue tiles and causes clay flue tiles to deteriorate or “spall.” An improperly built cement crown may allow rain water to deteriorate mortar and bricks faster at the top of the chimney than the rest of the structure, and a damaged crown will allow rain to damage the interior chimney.
The use of soft type bricks instead of hard type bricks allows rain water to penetrate the bricks more easily, which eventually causes the brick faces to pop off. Birds and animals may build flammable nests inside chimneys, which can cause poor draft or even carbon monoxide backup into the home.
According to the National Fire Protection Association, chimney fires account for at least 14,190 fires per year and at least $35 million in direct property damage annually. Most chimney fires go unnoticed by the homeowner and the resulting damage is found later by a chimney sweep.
However, some chimney fires are very loud and there may be flames shooting out the top of the flue and even through the side of the chimney. Homeowners should call the fire department immediately, because even if the fire goes out on its own, hidden combustibles near the chimney may smolder and ignite later. After a chimney fire, call an expert to inspect the chimney for damages, which will likely be present.
All chimneys and flues should be inspected annually by a trained professional who can identify problems that the untrained eye cannot. Furnace and water heater flues, boiler flues, fireplace flues, wood-burning insert and wood stove chimneys all need to be inspected in order to be certain that the chimney flue is the correct type, is sized correctly for the appliance and that the appliance is drafting correctly.
One of the most common errors chimney sweeps find is an oversized flue serving a newer furnace and water heater, or water heater alone. The wrong size flue can cause CO leakage into the home, poor draft, poor appliance operation and excessive condensation in the flue liner, which usually results in expensive chimney damage repair.
In completing a Level II chimney inspection of a fireplace, a chimney sweep will check the exterior of the chimney, the interior flue, smoke chamber, damper, fireplace and surround for gaps, cracks or breaks that could allow escape of toxic gasses and heat.
Many of these damages are not visible to the naked eye without the use of a special camera system designed for this purpose. A Level I visual inspection of the chimney or pipe is usually adequate for utility flues and wood stove chimneys.
Finding a qualified professional chimney sweep can be difficult, but with a little research, homeowners should be able to find someone local. The Midwest Chimney Safety Council lists Midwest area professional chimney sweeps on their website, and the Chimney Safety Institute of America has a list of U.S. and Canadian Certified Chimney Sweeps on theirs as well.
After locating a certified sweep, check their website for more information about their company. For repair work, request a certificate of insurance for liability and worker's compensation. Also check the Better Business Bureau and Angie's List to read customer reviews on the company before hiring them to complete any work.