It’s a classic image: curling up by the warmth of a cozy fire with a good book and a mug of hot cider. But what you can’t see in this picture may be harming you and your family. Burning wood emits toxins such as dioxin, arsenic, benzene and formaldehyde, as well as microscopic particles (also called particulate matter) that can cause burning eyes, runny noses and illnesses such as bronchitis. Particulate matter can also trigger asthma attacks and has been linked to heart and lung disease. Moreover, open fireplaces and older wood stoves are inefficient and often lose more heat than they produce. Fortunately, there are ways to bring the warmth of a well-tended fire into your home in a healthier and more efficient manner.
A More Efficient Fireplace
The American Lung Association recommends choosing cleaner, less toxic sources of heat than burning wood when possible. Although efficient fireplaces and stoves that burn natural gas or propane eliminate exposure to some of the dangerous toxins wood burning generates, they rely on costly, unsustainable fossil fuels. Gas and propane fireplaces and inserts must be directly vented outside the home to prevent exposure to carbon monoxide, nitrogen oxide and other emissions.
Pellet stoves are an efficient, cleaner-burning alternative, often generating less than 3 grams of particulate matter per hour. They are similar to wood stoves, but instead of wood, they burn other renewable fuels such as sawdust, woodchips and biomass wastes compressed into pellets. A pellet stove usually costs from $3,500 to $4,000 including installation, and they are available as inserts or free-standing stoves. Most models use electricity to control the flow of pellets into the stove. Use premium-grade pellets to help reduce ash buildup.
But for many people, nothing can quite replace the ambiance of burning wood. If you love the warmth of a wood fire, a new wood-burning stove or fireplace insert certified by the Environmental Protection Agency (EPA) is your best bet. They require less wood to generate the same amount of heat and emit fewer harmful particles–2 to 7 grams per hour compared with 15 to 30 grams for models manufactured before 1992. A new wood-burning stove or insert typically costs $3,500 to $4,200 with installation.
If you can’t upgrade your existing fireplace or stove, you can still improve its performance and reduce health risks. Have it inspected annually by a certified professional (see Resources). As often as the inspector recommends, hire professional cleaners to keep your system running smoothly and address dangerous creosote buildup, which can accumulate quickly in older wood stoves and fireplaces. A professional will also check for trapped debris and wildlife, which can force toxic gases back into your home. A well-designed chimney cap can help keep out animals and rain, as well as prevent sparks from landing on the roof or nearby combustible materials.
To help maintain proper airflow and prevent dust and soot buildup, shovel excess ash into a covered metal container and store it outside, away from your home. Once it has cooled for several days, ash can be disposed of with other household trash. You can also use it sparingly in compost piles and to “sweeten” soil if it has an acidic nature. Many plants such as lilacs respond well to the application of wood ash, but to avoid adding toxins to your garden, make sure to use ash only from untreated wood, not from trash or other materials.
Always keep the damper closed when your fireplace is not in use. If you use your fireplace only occasionally, you can help block heat loss through the chimney by cutting a panel of insulating foam board to fit snugly inside the base of the chimney opening. Remove it when you want to make a fire. If you never use your fireplace, you should seal and plug the flue to prevent heat loss.
Build a Better Fire
Whether you’re building a fire in a wood stove, an open fireplace or an outdoor setting, use these tips from the EPA’s Burn Wise website to make it safer, healthier and more efficient.
• Season wood outdoors through the summer for at least six months before burning it. Properly seasoned wood is darker, has cracks in the end grain and sounds hollow when hit against another piece of wood.
• Purchase a wood moisture meter and test the moisture content of wood before you burn it. Wood burns best when the moisture content is less than 20 percent.
• Never burn household garbage or cardboard. Plastics, foam and the colored ink on magazines, boxes and wrappers produce harmful chemicals when burned.
• Never burn ocean driftwood; coated, painted or pressure-treated wood; particleboard; plywood; or any wood with glue on or in it. They all release toxic chemicals when burned.
Each year in the United States, about 3,000 people die in residential fires–mostly from the inhalation of smoke and toxic gases, not as a result of burns. Install smoke detectors in your home and test them often. If you use a wood stove or any kind of fireplace, the EPA also recommends installing a digital carbon monoxide detector.
Alliance for Green Heat
information on choosing clean, efficient heating appliances
list of EPA-certified wood stoves; safe practices
Chimney Safety Institute of America
nonprofit organization dedicated to chimney and venting safety
Hearth, Patio & Barbecue Association
locate a hearth product retailer near you
National Fireplace Institute
find a certified professional to install and repair hearth products
alternative heating appliance reviews