5 Tips For Cleaner Fires From A Chimney Sweep

BY ON December 11, 2012

Baby in front of fireplace

This post was written by Kiera Butler for Mother Jones and used with permission:

It’s no secret that fireplaces and woodstoves—wonderful and cozy though they may be—are not great for the environment. The smoke that they produce is full of harmful particles, including, according to the EPA, volatile organic compounds and the likely carcinogen benzo(a)pyrene. Smoke can foul up the air both inside and out, and exposure to the stuff can cause serious respiratory problems.

So should you board up your hearth for good? Not necessarily. The right equipment can help, as can proper burning techniques.

To find out exactly how to make the most efficient fire possible, I enlisted the help of Clay Thompson, a working chimney sweep based in Sacramento, California. According to the Chimney Safety Institute of America, there are about 5,000 working chimney sweeps in the United States. You may be as disappointed as I was to learn that Thompson, who has been sweeping six chimneys a day five days a week for 13 years, says that unlike that other notorious chimney sweep, Mary Poppins’ boyfriend, he sings only in the car and never dances. Also, he uses brushes instead of, you know, climbing on in. “Most modern chimneys are only six inches wide,” he says. “I don’t know how Santa does it.” Anyway, here are Thompson’s tips:

1. If you have a fireplace, consider an insert. A fireplace insert is like a wood-burning stove that fits right into your fireplace. EPA-certified models burn 70 percent more efficiently than an open fireplace.

Upgrading to new equipment could save you money. If your fireplace insert or stove was made before 1992, you might want to consider a newer, EPA-certified model. Although they can be pricey, the agency-approved stoves and inserts not only produce less smoke and soot, they’re also 50 percent more efficient than traditional models—so you’ll end up spending less on fuel. They’re also much easier to clean, says Thompson: “I dread those old inserts. They weigh 600 pounds, and then there’s six to eight inches of soot inside. You can’t even see anything, and it takes two and a half hours. I have to change my clothes after that. I work as a chimney sweep but I don’t like getting dirty.” For several years, people who upgraded their fireplaces and wood stoves qualified for a federal tax credit, but that program expired this year. Some states offer their own programs; the Alliance for Green Heat lists them here.

3. Burn the right kind of fuel. Rule of thumb: The cooler your fire, the more particulate emissions and soot it produces. In order to ensure that your fire is hot enough, Thompson recommends using only wood that has been “seasoned” (dried) for at least a year. Hard woods (like maple, ash, oak, and beech) burn hotter than soft woods (pine and fir). Most importantly, never burn wet wood. Pellet stoves, which take bricks made of compressed wood or other organic materials, generally burn cleaner and more efficiently than woodstoves or fireplaces. This EPA chart compares particle emissions from various heat sources:

Heat source particle emissions chart

Image courtesy of EPA

4. Use the right sized grate for your fireplace.
“A lot of people buy a grate that is too big for their fireplace and then spread out the logs,” says Thompson. For the hottest and hence cleanest-burning fire possible, “you want those logs all bundled together in the center.”

5. Skip the home chimney-cleaning remedies. There are a bunch of old wives’ tales about DIY chimney sweeping; Thompson says that several of his customers have tried to clean their chimneys by starting a fire with potato peels or rock salt. “Those don’t seem to work.” Another bad idea: “Some people try to start a chimney fire to clean their chimney,” he says. “Sometimes it does clean it, but sometimes it burns your house down.” For newer model fireplace inserts and stoves, Thompson recommends a professional inspection and sweeping about every two years, or one cleaning for every cord of wood burned. But if you have older equipment, or if you regularly burn wood that isn’t properly seasoned, you could end up needing a sweeping much more frequently. Thompson’s company charges $149 for a one-story sweeping, but prices vary by region.

It should also be noted that the while fuel stoves in the United States are often considered ornamental, Europeans are increasingly using pellet stoves as a primary source of heat. The Alliance for Green Heat points out that these stoves produce fewer climate-warming greenhouse gases than fossil fuels.

Wood and pellet stoves are far from the only hearth-based heat contraptions available. If you’d like to geek out on hydronic heaters, masonry heaters, and more, the EPA’s site on appliances is a good place to start. Want to compare efficiency and emissions of various models? Go further down the rabbit hole with Cornell Cooperative Extension’s extremely thorough guide.


TOPICS: Asthma, Michigan, New Hampshire, Ohio, Pennsylvania, Pollution

  • Ernest Grolimund

    EDF and other env groups are requesting the EPA tighten stack stds for certified stoves. The ALA is writing that 88% of certified stoves emissions are unhealthy and so their emissions should be made less as required by NSPS law. These stds were supposed to be reviewed every eight years but have never been reviewed, till now.
    Logically, if 88% of the certified stoves are unhealthy per ALA, then the old stoves common in NH are very unhealthy. If the certified stoves allow 100 mcg/m3 pm2.5 conc’s in nightly inversions, and the safe dose for wood smoke pm2.5 is 180 mcg/m3,hr , per ATSDR, then it is 2 hours or less to unhealthy conditions that must be stopped and prevented per DHHS policy for essential services.
    NH mobile monitoring shows community wide pm2.5 at 100 mcg/m3 in Keene NH. But the pm at houses is about 300 mcg/m3 from old stoves per EPA and BAAQMD modeling in ME and CA. Just cleaning old stoves and certified stoves is not enough to solve this problem. They have to be removed following recommendations from the U.N. to phase out all cordwood burning fast. Changeout programs are too slow. London solved the London Fog Air Pollution Disaster problems from fireplaces by banning fireplace use. Keene should do the same and consider banning the old stoves to prevent health problems and even consider banning certified stoves unless the emission factor is equal to oil emission factors. Otherwise, the city is going the wrong way on air pollution and warming and mercury deposition problems in fish.
    This is not just a Keene problem or a NH problem. NH is just ahead of the country in discovering this problem and should be commended for its work so far. Both Keene and NH should call in the EPA and ATSDR like NY and Michigan have done to stop this very bad air pollution problem. The constitution requires it and it requires changing the old rules and laws too if they are no longer protective. This is the job of the legislature and congress but informed people have to communicate their concerns to the politicians or they will not know about the problem. They have thousands of issues facing them and it takes a united voice to get their attention. EDF leaders are dong their part, so I ask EDF rank and file to add to that voice.

  • Ernest Grolimund

    FIRST: Engineering professionals have been leading the way to clean air for 100 years by promoting the change to cleaner energy sources. They helped the country transition from polluting or injurious wood heat to coal heat to oil, gas, electric, heat pumps,solar, and insulation and conservation. Follow their lead. It is wrong to go back to wood.
    SECOND: Weatherize. Reduce infiltration by replacing weatherstripping on windows and doors. Use tape if you have to. It’s dirt cheap poor people. Can cut bills in half in old leaky houses frequently lived in by the poor. You don’t have to replace windows in most case.
    THIRD: Insulate. Insulate more. Superinsulate. Insulate windows like Jefferson did with shutters. Insulate enough and you can heat your house with free solar energy streaming through windows. This generates an annuity of free money in a way for life. FREE, after the initial expense of insulation is paid off.
    FOURTH: Swich to engineered pellet stoves or search out the new gasifier stoves with emission factors equal to oil and no damper that can increase pollution tremendously by choking needed combustion air.
    FIFTH: Switch to leveraged electicity in the form of heat pumps to supplement oil heat until cheaper gas can be brought in perhaps or as a switch from even gas. In NH they do not work as well in deep winter but in fall and spring they are great and can save you money. Buy your electricity from clean renewable sources like hydropower, windpower, and yes even nuclear power when it is available.
    Be a true conservative and conserve resources including our all important air and this garden earth. Beware the fiery furnaces as Jesus warned and the fire and smoke of Ghenna (mistranslated as hell), which is what the smoke engulfing Shelbourne Falls, MA is like. A photo on http://www.MassCleanAir.org shows the town in a cloud of wood smoke. Remember the Golden Rule that trumps all the grandfather rules and do not do anything that can kill, injure, poisen through air pollution.
    Follow the lead of EDF Atty Patton in challenging NSPS stds with the EPA and challenge the local towns negligance in not enforcing their nuisance laws and not controling the air pollution that shojuld be evident to everyone by now. Small sources are the new large source of pollution for provonces aroujnd NH are showing pm going into the air as doubling or tripling and this means the pm conc’s are doubling or trip;ling on average tholugh the monitors are set up by law to avoid “hotspots” or wood smoke. Model the hourly pm from all apliances and match it to known stds and guidelines as well. Make sure the emissions are safe. Clue: If the design level from oil and gas combustion is about 25 mcg/m3 and the legal std is 35 mcg/m3, then do not use more polluting sources of energy, because there is no room for error between the design pm and the std. There needs to be a safety factor for good civil engineering. After all, The consensus scientific std for the world is 25 mcg/m3 for pm and it is likely we are over that on average and definetly on the higher end of the average. The intent of the clean air act is to protect all the people including babies “ANYWHERE”, not just at the pm montors.
    A flaw in the pm monitring system is suddenly apparent. It worked when oil and gas were burned since furnace pm was .1 mcg/m3 and not detectable except by the monitors that could seemingly be placed anywhere. But with pm from an old stove at 300 mcg/m3 and the new safe dose from wildfire smoke and wood smoke at 180 mcg/m3, something has to change to protect constitutional rights to life and health. When governments lose their respect for life itself, then there is gross criminal negligance.
    That is part of the reason why EDF atty’s and other env groups are trying to challenge the NSPS stds. Another reason is that 90% of the people polled in ME said they disliked tobacco smoke in their environment and 80% in Fort Collins CO want nuisance laws to be enforced for wood smoke. Even states are asking them to do this in some instances.

  • Smoke kills

    Ban all wood burning period Wood Smoke is toxic. http://burningissues.org/forum/phpBB2/viewtopic.php?f=15&t=2091

  • Ernest Grolimund

    EDF and CAC filed intent to sue EPA on wood burning stack stds. Good work. CAC says that they are leaning to sue to get old stoves phased out rapidly to follow U.N. consensus science that cordwood burning is bad for health and climate. Even certified stoves. Even if burned wisely which is really unwisely. 500 times more pm emissions with even burn wise operation. 500 times more black soot and climate change pollution. Lot’s of safe alternatives. Let’s all give EDF and CAC a cheer. And a special thanks to Gretchen Alfonso. When I called her, she understood the problem and called Clean Air Council to bring them on board. Everyone did a lot of studying first but finally came on board.
    They even got 4 states to join them: NY, CT, MA and RI. ALA and EHHI too. Good going Nancy Alderman and Dr Brown. Good going NYSERDA. The problem is not the EPA or DHHS by the way, it is the whitehouse and congress. The suit should be a piece of cake as the EPA is on our side and DHHS is on our side. There is just this little problem of damages to 1/3 the population since about 2007. Sue for damages and then use the money to stop the deaths and injuries and sickness from the old stoves. It is only $3,000/burner/yr or $150 billion/yr nationally. And the climate problems are costing us even more. So much for cheap wood energy. Have to add in the social costs.

  • JulieB

    I really think you should remove this story. Wood burning, especially in a fireplace creates an enormous amount of hazardous pollutants inside and outside for you and the neighbors. The baby in front of the fireplace is a poor choice too.

  • Quite nice and informational post thanks………….

  • Bill Lewin

    What silly advice from a clean air organization ” DON’T BURN” is the only good advice

    • Mcat

      So fireplaces create 97 pounds of soot per year,does this reduce it to 96.5 pounds? Or does it just reduce it for the burning household and the 97 pounds of soot aka Particulate Matter invades the neighboring homes? Just wondering.

      • Bill Lewin

        Judging from the so called clean burning EPA wood stoves in my area I’d say all that soot and pm2.5 ends up in neighbouring homes

  • VicSteblin

    A wood smoke cost that is often ignored is the cost of municipal fire prevention.
    A retired fireman told me that municipalities would need fewer firefighters if
    wood stoves were banned. Additional required insurance for houses that have
    wood stoves also proves this expensive reality.

    The early days of unsafe natural gas furnaces also had their share of tragedies. I
    recall a house that blew up and one of the survivors ended up in a nearby tree.
    The wood burners said, “Beware this new technology”. Since those early days, improved
    furnaces have a much better safety record.

    Even with modern wood stove safety regulations, wood heated homes cause many
    needless tragedies. Creosote chimney fires are a regular call out for fire
    departments compared to none for natural gas flues. And chimney sweeps cost $$$,
    whereas no one has to clean out a natural gas flue.

    My retired friend said “the true costs of wood stoves are largely ignored by
    municipal governments”. In these days of looking for savings, officials should
    “open their eyes” and ban wood stoves where natural gas is available.