State University Extension
Home Maintenance And Repair - 01500595
If constructed properly, fireplaces will perform safely and dependably.
Fireplaces, just like anything else, wear over a period of years and
need to be maintained to extend their life. Here are check lists to
follow for safely installing, maintaining and operating a fireplace.
Check to determine that the fireplace complies with all building codes
in your community, including special requirements such as earthquake
construction. Be sure the flue is of adequate size, equal to at least
1/ lOth the area of the fireplace opening for chimneys more than 15
feet tall and at least 1/ 8th the area of the fireplace opening for
chimneys less than 15 feet. Extend the chimney at least 3 feet above
the highest point where it passes through the roof and at least 2 feet
higher than any portion of the building within 10 feet. If the roof is
flat, the chimney should be at least 3 feet above the roof.
Be sure the flue is tight, well-built and well- maintained, with a
smooth interior. Each fireplace needs its own flue, but more than one
flue may be located in the same chimney.
Extend the hearth in front of the fireplace at least 16 inches into the
room and at least 8 inches on either side of the fireplace opening. Use
brick, stone, tile, concrete or other non-combustible, heat-resistant
material at least 4 inches thick.
Support the chimney and fireplace properly. Wall-hung chimneys and
fireplaces are apt to put undue weight on walls and partitions, cause
the floors to settle and cause masonry flues to crack. A masonry
chimney should rest on its own foundation below the frost line.
Install metal flashings to protect areas where the flue goes through
the roof, and keep them in good repair.Install a metal spark arrester
on top of the chimney to keep sparks from setting the house afire.
Be sure prefabricated metal fireplaces and chimneys are approved by the
Underwriters' Laboratories (UL) and installed as specified by the
instructions. Free-standing fireplaces should be at least 3 feet from
unprotected walls, drapes or other flammable materials. Use necessary
wall protection to protect walls closer than 3 feet. Place a pad of
brick or insulated fireproof material on the floor beneath the
fireplace. Be sure that pipes connecting free-standing stoves and
fireplaces to a chimney are at least No. 24 gauge steel, UL listed and
installed in accordance with the listing. No pipe should be longer than
10 feet nor more than 75% of the vertical height of the chimney,
whichever is less.
For a modified fireplace (a firebox inserted into an existing
fireplace), select one with a steel liner at least 1/4-inch thick to
decrease the likelihood of it eventually rusting out.
Install bird and animal guards on the chimney. Squirrel and bird nests
can stop up chimneys.
If you choose a natural gas "log," follow instructions for installation
and use. Look for the American Gas Association label.
Maintenance for Safety
Keep the fireplace in good condition by repairing cracks in the flue
lining, bricks and mortar.
Keep the flue clear of soot, creosote and obstructions. Inspect the
fireplace and chimney at least once a year to prevent creosote buildup.
Equip the house with fire-warning devices. Install a type ABC fire
extinguisher near the fireplace. Install a screen that completely
covers the fireplace opening to keep sparks from flying out. Keep
combustible materials such as carpets, furniture, paper, logs and
kindling at least 3 feet away from the fireplace. Arrange andirons so
logs can't roll out.
Use only enough fuel to keep the fire at the desired temperature. Avoid
"roaring" fires. They can start chimney fires from soot and creosote
deposits in the flue.
Do not use gasoline or other flammable liquids to kindle or rekindle a
fire because the flammable vapors can explode. Never use fuels near a
fire; explosive vapors can travel the length of a room.
Keep the damper open while the fuel is burning to provide for efficient
burning and to prevent accumulation of poisonous or explosive gases.
Never burn Christmas tree greens. They cause many sparks when burning
and can cause a chimney fire.
Remove colored comic sections before rolling newspapers into logs. The
colored inks contain lead and can produce toxic gases.
Do not use coal, charcoal or polystyrene packaging in a fireplace
unless the fireplace is designed to handle the excess heat and smoke
which occurs when burning these materials.
Do not treat artificial logs (made from sawdust and wax) the same way
you treat real wood logs. Use only one at a time. If you use more, they
can produce too much heat for some fireplaces to withstand.
Keep children away from the fire because their clothing can easily
ignite. Warn the entire family about this hazard.
Be sure that all ashes have thoroughly cooled before you dispose of
them. Put ashes in a lidded metal container to prevent a possible fire
and provide a sturdy place to store them. Ashes make good fertilizer in
gardens, flowerbeds, etc.
Be sure the fire is out completely before retiring for the evening.
Safe Supply of Air
A fireplace fire requires about 5 times as much air as most houses need
for liberal ventilation. With today's tightly-constructed houses
incorporating weather-stripped doors, caulked windows and self-closing
exhaust vents, a fireplace can set up reverse draft and suck poisonous
carbon monoxide fumes from combustion-type (natural gas, etc.) water
heaters or furnaces and discharge them into the living area.
In tight homes, the fireplace may also consume enough oxygen from the
air in the house to cause problems to occupants. To be safe, a positive
source of outside air should be supplied to all fireplaces and
wood-or-coal burning stoves to bring in enough fresh air for efficient
burning. This can be provided by installing an outside air vent or
opening a window when the fireplace or stove is being used. To keep
smoke from entering the room, turn off kitchen and bathroom exhaust
fans and close the registers of forced air heating systems which are
near the fireplace.
This information comes from Michigan State University Extension
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This information is for
educational purposes only. References to commercial products or trade
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not mentioned. This information becomes public property upon
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are open to all without regard to race, color, national origin, gender,
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beliefs, sexual orientation, marital status, family status or veteran
status. Issued in furtherance of MSU Extension work, acts of May 8 and
June 30, 1914, in cooperation with the U.S. Department of Agriculture.
Thomas G. Coon, Director, MSU Extension, East Lansing,MI 48824. This
information is for educational purposes only. Reference to commercial
products or trade names does not imply endorsement by MSU Extension or
bias against those not mentioned.
information.was reviewed as
of June 2008. For more information about the contents please
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