Assessing your Home for Wood Heat
If you've never burned wood for heat, if your home hasn't had a wood-heating appliance in continuous winter use in recent years, or if you plan to install a new wood-heating appliance, you'll need to inspect the chimney and make sure the house is set up to burn wood in the intended appliance safely and efficiently.
Consult an expert
If you feel unsure about your own ability to make the assessments recommended here, please consult an appropriate professional or town official to help you. Woodstove vendors may offer home assessments, stove installations, and referrals to experienced chimney professionals, masons, builders, or energy auditors. Some vendors offer a complete array of woodstove services.
Check with local fire and building officials before you install a wood stove
Although New Hampshire has adopted the National Fire Protection Association's 211 Standard for chimneys, fireplaces, vents, and solid fuel-burning appliances, some cities and towns have adopted additional requirements, which typically involve inspection of the wood heating appliance before use. Contact your town fire department or building inspector to make sure your plans follow all state and local regulations.
Notify your insurance agent of your plans to install a wood heating appliance
Each insurance carrier has its own standards regarding installation, inspection, and other aspects of heating an insured home with wood. Your agent can advise you about how to proceed and whether you'll need to modify your current coverage.
Inspect your chimney (or have an expert inspect it)
Wood stoves must be connected to a lined chimney with a flue of adequate size to carry the smoke from your wood heating appliance.
(Note: A wood stove can't share a flue connected to another fuel source such as heating oil or propane.) You may want to hire an experienced chimney professional or mason to inspect your chimney and recommend repairs or other changes.
The Chimney Safety Institute of America (CISA) homepage has a good tutorial on the various levels of masonry chimney inspections. This nonprofit association also certifies chimney sweeps. The Canadian nonprofit woodheat.org has an excellent primer on how chimneys work and how to avoid common chimney problems.
Your local building inspector or fire official may make chimney home inspections. If not, they probably can refer you to an experienced chimney sweep or mason who can. Before you hire, ask for credentials or certifications, and ask for and check references from previous clients.
Make sure you have a good location for the stove
Will your home's design and layout accommodate a wood heating system?
First, consider how the heat from your wood stove will move around and through the living space you intend to heat. While central heating systems (including indoor and outdoor wood furnaces) use pumps and fans to distribute heat throughout the building, wood stoves radiate heat directly into the space around them.
Although some stoves come equipped with fans, and some stove users install fans to help distribute the warm air, the air warmed by the stove's radiant heat rises through natural convection, through open stairwells, ceiling grates and other spaces between levels of a dwelling, gradually displacing cooler air to warm those areas farther from the stove.
Follow manufacturer's instructions
Although it makes sense to locate the stove or stoves in the rooms where people spend the most time, your home's design may not permit a woodstove installation in one of them. Each wood-heating appliance will have specific requirements for safe distances ("clearances") between the stove/stovepipe and the room's walls and other combustible materials.
To comply with state and local codes, follow the manufacturer's instructions for installation and maintenance of your stove. If you bought a second-hand stove that came without an owner's manual, contact the manufacturer to get one for your model. If you can't locate a manual, or you have any questions about safe woodstove installation procedures, call your local fire department or building inspector for help.
"Backdrafting" occurs when a woodstove puffs smoke into the living space instead of up and out the chimney. It's always a bad sign. Wood smoke should never enter your living space. An inadequate or clogged chimney can cause a backdraft.
Like all fuels, wood needs oxygen to burn. A woodstove needs air for combustion and also for the draft, to keep combustion gases (smoke) going up the chimney. Typically, woodstoves draw their combustion air (sometimes also called "makeup air") from inside the house.
Well-insulated homes that contain other vented appliances such as kitchen and bathroom exhaust fans, clothes dryers, water heaters, and furnaces, may not always have enough inside air available to allow efficient operation of woodstoves. When other power-vented appliances switch on (see diagram to the left ), they can overcome the natural draft of the chimney and pull wood smoke down and out through the stove into the living space.
Consult your stove vendor or a heating and ventilation professional experienced with wood heating systems if:
- You have difficulty getting a wood fire started or you can't keep a fire going.
- You smell smoke or get soot on your walls.
- Your carbon monoxide detector keeps sounding alarms.
Designed more for show, traditional open masonry fireplaces should not be considered heating devices... Only high-efficiency fireplace inserts have proven effective in increasing the heating efficiency of older fireplaces. Essentially, the inserts function like woodstoves, fitting into the masonry fireplace or on its hearth, and use the existing chimney. A flue collar must be installed that extends from the insert to the top of the chimney. A well-fitted fireplace insert can function nearly as efficiently as a woodstove.
A note about rental housing
If you live in rented housing, contact your landlord before installing a woodburning appliance. If you do install one, or if the unit already contains a woodstove you plan to use, learn all you can about safe woodburning and follow the guidelines faithfully. Consult experts or local fire officials if you have questions or concerns.
Reviewed by J. William Degnan, N.H. State Fire Marshal, who also contributed.