Santa Claus wasn't the only one up on the rooftop this winter.
Chimney sweeps, made famous by the movie "Mary Poppins," don't wear black top hats and dance on housetops, but their profession, cleaning chimneys, can save lives.
According to a report on residential fire losses for 2008-2010 that was compiled in September by the U.S. Consumer Product Safety Commission, heating and cooling equipment constituted the second largest share of total residential fires -- behind only cooking equipment -- with an annual average of 51,800 fires reported and 210 deaths.
Fireplaces and chimneys were by far the largest single cause of such fires, accounting for an average of 25,900 fires and 20 deaths each year.
The Chimney Safety Institute of America is a nonprofit that certifies chimney sweeps by testing their knowledge of safety, codes and standards. Membership to an industry group, such as CSIA, isn't necessary for chimney sweeps, although they need to be licensed as contractors in Pennsylvania.
The CSIA and the National Fire Protection Association recommend annual inspections and chimney sweeping to reduce the risk of fire or carbon monoxide poisoning, but Michael Schock, president of Advanced Chimney Sweeps in Uniontown, said he feels it's sufficient to clean a chimney once a year, or after each cord (a 4-foot-by-8-foot bundle) of wood is burned, whichever comes later. Other experts said they believed cleanings every three or four years are sufficient, though inspections should be done on an annual basis, they said.
George Spanos, owner of Nickos Chimney Co. in Unity has been a chimney sweep for 35 years and said he thinks that cleanings every three years for fireplaces that are occasionally used is sufficient. But wood-burning stoves or other similar devices used to heat homes through the winter should be inspected annually, he said.
Inspections are classified by level, with a basic visual inspection of the interior and exterior of the chimney in Level 1. A technician will check the basic condition of the chimney structure and flue and will look for obstructions or a buildup of combustible deposits in the flue.
A Level 2 inspection should be done if there has been a change, such as the relining of a flue, or during a routine home purchase inspection. A Level 2 inspection is also recommended if there has been an operational malfunction, fire, earthquake, chimney damage or strong storm. To complete this type of inspection, a technician will gain access to the roof where a video scanner can be used to inspect the interior of the chimney and its parts.
A Level 3 inspection occurs when special tools are necessary to gain access to concealed parts of the chimney.
The cost for a Level 1 inspection and cleaning locally ranges from $150-$200, depending on the company and whether the work will be done in the peak season, which runs from late summer through late winter.
The CSIA recommends that before a technician inspects your chimney, you should avoid lighting a fire for 24 hours and you should remove furniture and breakable items from around the fireplace.
The technician will clean the chimney and contain dust and soot through a HEPA filtration device that prevents particulate matter from entering the home. Technicians usually wear coveralls and a respirator and use drop cloths during this procedure, which takes about 60 to 90 minutes.
Technicians use special plastic or wire brushes to sweep the flue liner and smoke chamber -- the area between the fire box and the flue.
To prevent scratches to the interior glaze of the flue, brushes with plastic bristles are used for light buildup. Heavier, more stubborn deposits might have to be removed through the use of chemicals and wire brushes.
The deposits are creosote, tiny tar droplets that form as a byproduct of burning wood.
Whether using certain types of wood contributes to creosote buildup depends on who you ask.
Mr. Schock and Mr. Spanos believe high-sap woods, such as pine and other evergreens, contain more resin and therefore produce more creosote. For that reason, they do not recommend using pine except as kindling or tinder. Wet, green or treated wood also produces excessive creosote and should be avoided as well.
Mr. Schock, 42, said that of the dozens of chimney fires he investigates each year, more than half are caused by burning pine or wet wood.
His company is the largest chimney company in Pennsylvania, with multiple locations throughout the Pittsburgh region. Employees clean and inspect more than 2,000 chimneys every year and his company is contracted with 25 insurance companies to investigate chimney fires. He conducts at least 80 fire investigations each year and another 20 that involve carbon monoxide leaks from other types of chimneys and flues, such as those associated with hot water tanks and furnaces.
Mr. Schock said that while most homeowners recognize the importance of maintaining their fireplace chimneys, few realize the dangers of not inspecting the other types.
"They don't understand how frequently these incidents happen," he said about carbon monoxide leaks. "It's a heat source that you use every day, so I would put more emphasis on my furnace than I ever would put on a fireplace. All of them should be inspected annually."
Accelerants, such as gasoline, also should "never, ever" be used in a fireplace, he said. Instead, you can use pine cones or prepackaged wax burners to light a fire.
Before every fire, Mr. Schock recommends opening the damper to the flue and holding up a lit piece of paper or wax burner. This allows the flue to warm up and to change the air buoyancy, creating an upward flow of air.
Air flow balance tricky
Maintaining that upward flow is a difficult balancing act in some homes, according to Bradley Powell, owner of Totally Exhausted in Franklin Park. A chimney sweep and mechanical engineer for 40 years, Mr. Powell said he has seen downdrafts caused by the seemingly insignificant changes -- such as having a pet door installed or canned lighting in a cathedral ceiling. The lights allow small pockets of air to form, altering the air flow in the home.
"We get calls on that constantly," Mr. Spanos said of homeowners complaining about downdrafts. "We can fix any draft issue. It's a process of elimination. Any fireplace can be corrected."
The best way to keep a chimney clean, Mr. Powell has found in sweeping 1,200 each year, is to burn a "good, hot fire."
"I change people's burning habits all the time and we come back in a year or two and the difference is amazing," he said.
Mr. Powell, 60, thinks creosote buildup is more a product of condensation than wood resin.
"Creosote is just tar and soot that didn't burn off in a fire, not resin," he said.
Rather, Mr. Powell said overusing gas starters on wood-burning fireplaces is the No. 1 contributor to creosote that he sees. Because the starters superheat the air, they create more initial condensation, Mr. Powell said, so they should be used to light fires for only a maximum of 10 minutes.
"In it's simplest form, it's incomplete combustion," Mr. Spanos said of creosote. "If you see smoke, you know there's going to be creosote. You should only see smoke coming out of your fire when you light it or when you add wood."
Though smoke is a sign that creosote may be building up in a chimney, clear vapors are a good sign, he said, meaning that the fire is burning cleaner.
Mr. Schock said the easiest way to think about how a chimney works is to relate it to the human body.
"The chimney is the lungs of a house," he said. "So if your chimney becomes blocked, the products of combustion can't exit the home so they'll go into the house."
Mr. Spanos, 64, a chimney sweep for 35 years with 1,000 regular customers, recommends using hardwoods in a fireplace, such as cherry, maple, oak or locust.
Chimney Sweep Guild trains
Mr. Spanos is a founding member of the Pennsylvania Chimney Sweep Guild, a nonprofit group that sponsors training, education and networking opportunities for those who work in the industry.
He started the business in 1977 when he and his wife bought a historic home in Greensburg with six fireplaces.
"I had no idea what to do," he recalled. "I had never lived in a house with a fireplace. There were bricks and soot all over the place, and I realized nobody in this area was doing that kind of work."
Because of his interest in historic properties, Mr. Spanos does a lot of restoration work, but he also isn't afraid to try something more modern. Next year, his store along Route 30 in Latrobe will offer a new remote-controlled, wood-burning fireplace that can be lit with a cell phone application.
Other common problems that chimney sweeps have to contend with are animals inside chimneys and construction mistakes.
Mr. Powell said he frequently finds the wrong type of brick has been used to construct a fireplace, or it isn't the required thickness to withstand high temperatures.
"Most of the problems stem from the fact that they're all built wrong," said Mr. Powell, who estimates that only about 1 in every 300 fireplaces that he inspects have been built up to code.
He recommends using stone instead of brick to build a fireplace, or purchasing pre-fabricated fireboxes.
"Pre-fab fireplaces are pretty foolproof," he said. "They work pretty good."
Sweeping the swifts
Mr. Schock said he often finds nests for an array of animals inside chimneys, including squirrels, raccoons and chimney swifts, a type of migratory bird that is a protected species under the Migratory Bird Treaty Act of 1918. Such bird nests cannot legally be removed from a chimney until they are abandoned.
He recommends the installation of a rain cap with a spark arrestor, which acts as a screen to keep the furry warmth-seekers at bay.
Mr. Powell said one way to keep raccoons and squirrels from nesting in a chimney is to be sure that there are no low-hanging branches above the rooftop.
"As long as they don't have access to your roof, you're OK," he said.
Janice Crompton: email@example.com or 412-851-1867.