WOOD STOVE SAFETY

Heating with solid fuel requires that you become aware of these and other hazards and take whatever action is needed to correct them.

TYPES OF WOODBURNERSwoodburning appliances

There are many different types of woodburners available. For example, there are circulating and radiant; woodburning furnaces; and fireplace inserts or hearth stoves. Safety requirements will vary by the type of unit you choose.

Generally, factory-built woodburners that are "listed" by a nationally recognized testing laboratory are superior to homemade units because of better construction, design, materials, and testing. For example, woodburners that are homemade have unknown clearances and may use a material that is too thin or deteriorates easily. In addition, be aware that barrels, drums or other containers that stored chemicals or flammable materials may pose health hazard.

PLACEMENT OF WOODBURNER

The proper placement of a woodburner is critical. Remember that all woodburners must be installed to comply with local fire/building codes and manufacturer's specifications. Have a qualified heating contractor experienced with woodburners install your unit.

If your community does not have an ordinance covering these types of units, make sure your unit is installed to meet the National Fire Protection Association (NFPA) Standard #211: the Standard for Chimneys, Fireplaces, Vents and Solid Fuel Burning Appliances. NFPA #211 is a nationally recognized standard on solid fuel burning appliances.

CLEARANCES

Some general clearances requirements:

WALLS
NFPA #211 recommends that freestanding woodburners (not including furnaces) have a minimum 36-inch clearance to combustible materials on all sides. Clearance requirements are different for other types of woodburners, such as furnaces.

The high temperatures produced by the unit can actually decrease the temperature at which the wall coverings (for example wood paneling) will ignite. Walls can be protected by noncombustible wall protectors or shields to reduce clearances Prefabricated wall protectors are available and should be installed according to the manufacturer's instructions and "listed" by a recognized testing lab.

Sheet metal, brick veneer, drywall, aluminum foil, etc., placed directly on a wall is not considered an approved wall shield. Heat will still penetrate through the material and could start a fire in your home.

FLOORS
minimum clearances
Floors with wood, carpet, linoleum, and other combustible coverings must have a floor protector underneath, in front of, to the sides, and to the rear of the heat producing appliance. The type of floor protection to use will depend upon the type of appliance you have. Review your owner's manual for details on floor production. Prefabricated floor protectors are also available. The floor protection should provide a sturdy base and extend at least 18 inches on all sides of the heater.

STOVEPIPE
Stovepipe is used to connect the stove to a chimney. Clearances between the stovepipe and combustible materials are equally important as those given for the woodburner. Unprotected walls and ceilings need at least 18 inches of clearance from the stovepipe. Stovepipe sections should be securely fastened together by screws and have the crimped ends pointing down. The length of the stovepipe should be as short as possible. To connect to a chimney, follow your instruction manual or use an insulated pass-through device that has been "listed" for that purpose. Never use stovepipe as a chimney or pass it through an unprotected wall.

CHIMNEYS

fireplace requirement The consumer Product Safety commission estimates that about 45,000 chimney fires occur each year. These fires are often a result of poor maintenance and inadequate cleaning of the chimney.

MASONRY CHIMNEYS
Masonry chimneys should have a flue liner to help reduce the possibility of the masonry absorbing creosote. If the flue liner in your chimney is cracked or damaged, it may allow creosote to accumulate and heat to escape. This could increase the chance for a chimney fire. Several products are available to reline your masonry chimney and repair a damaged flue.

FIREPLACE INSERTS OR HEARTH STOVES
These types of woodburners should have the vent directly connected to the flue of the chimney. This positive connection is intended to reduce the creosote accumulation in the flue.

FACTORY BUILT METAL CHIMNEYS
chimney requirements Factory built metal chimneys specifically designed for use with a solid fuel heater are often called prefabricated, Class A, or all-fuel chimneys. Do not try to use a natural gas or fuel oil vent, well casing, stovepipe, or other material as a chimney. These materials are not designed to withstand the high temperatures produced by a woodburner. Most prefabricated metal chimneys have a minimum of 2 inches clearance to all combustible materials such as wood studs or joists and any type of insulation.

CHIMNEY MAINTENANCE
All chimneys (metal or masonry) require special care so smoke and flue gases are properly vented. Have your chimney inspected and cleaned before each heating season. Some of the things to look for include the items in these pictures.

masonry chimneyBesides having your chimney inspected, you should also have it cleaned regularly to reduce creosote. Creosote accumulates in stovepipes and chimneys and may ignite unless it is removed periodically. Creosote is mainly caused by slow smoldering (smoky) fires, cool surfaces, and burning unseasoned wood. Creosote buildup varies with the type of fires you burn, heater design, draft and the type of chimney. A rule of thumb is to clean a chimney whenever there is more than 1/8 inch to 1/4 inch of creosote. At the very least, you need to clean the chimney on an annual basis. Chemical chimney cleaners are generally not effective in reducing creosote buildup.

MULTIPLE VENTING
A special note of caution on using a chimney: only one woodburner or heater should be vented into a single flue. If a woodburner is connected to a flue already used by another heater, serious problems may arise:
1. Increased creosote accumulation.
2. The possible deterioration of the flue.
3. The blocking of a lower heater vent by creosote.
4. The flue may not be large enough to handle an extra heater and allow carbon monoxide to drift back into your home.

 

metal chimneyWoodburners must be used carefully. Some basic precautions you should follow when using your unit include:

1. Read the instruction manual that came with your woodburner.

2. Never use any type of flammable or combustible liquid to start a fire! This includes gasoline, kerosene, lighter fluid and other flammable liquids.

3. Do not burn plastics, garbage, wood that has been treated with a preservative, paint, or other chemical. These materials can cause corrosion in the heater, the vent and in chimneys, or produce dangerous toxic gases that could be harmful to you and your family. It is best to avoid smoky fires and use only well-seasoned wood.

4. Children should be taught not to touch or play around the stove.

5. Burn wood in your unit according to manufacturer's recommendations.

6. When cleaning ashes out of the unit, put them in a metal container that has a metal lid. Place the container on a concrete floor or other noncombustible surface, away from other combustible materials outside your home. Do not place the ashes in a paper sack or cardboard box; there may still be a hot ember that could ignite the container. Embers may stay hot for several days.

MAINTENANCE OF YOUR WOODBURNER

Keeping your woodburning system maintained is important. Solid fuel units require more maintenance than other types of heating systems. Regular maintenance is vital to their efficiency and safe operation. Some areas you should review on a regular basis include:

  • Look for cracks or breaks in the joints or welds of the unit. If you find any, have a qualified person repair it immediately! Do not use the woodburner until this problem is corrected.
  • Check the condition of your firebrick liner in your stove (if applicable). If the liner appears to be wearing out, replace it immediately and discontinue using the heater until the liner is replaced.
  • A stovepipe can deteriorate and should be replaced if it is suspected of burning out. Be sure that the joints are securely fastened together by screws.

FIRE PROTECTION

SMOKE DETECTORS/CARBON MONOXIDE DETECTORS
These detectors are desirable for any home, but are especially important if you have a woodburner. Place detectors throughout the house as the manufacturer recommends. Make sure the unit is UL "listed" or Factory Mutual (FM) approved and is tested monthly.

FIRE EXTINGUISHERS
In addition, place a multipurpose fire extinguisher in the same room as the heater. The fire extinguisher should be UL "listed" or FM "approved" and have at least a minimum rating of 2A-10B:C. Check the extinguisher monthly.