How to Use Your Fireplace Safely in Winter
Fireplaces cause over 20,000 home fires every year—and most are preventable. The difference between a warm, ambient evening and an emergency comes down to four things: the right wood, an open damper, careful ash disposal, and never walking away from live coals.
Quick Summary
Time Required
20 minutes per use
Difficulty
Easy with knowledge
Cost
$300–$500/cord of seasoned wood
Choosing the Right Firewood
Wood selection is the single biggest factor in safe, efficient burning. Wet or soft wood creates creosote, the sticky flammable residue that causes chimney fires.
Burn only seasoned hardwood
Oak, maple, hickory, ash, and birch split and dried for 6–18 months are ideal. Hardwoods burn longer and hotter than softwoods. Avoid pine and other resinous softwoods except for occasional kindling.
Test moisture with a meter
A $20 pin-type moisture meter pressed into a fresh split face should read below 20%. Readings above 25% mean the wood is too wet to burn cleanly.
Never burn treated, painted, or construction wood
Pressure-treated lumber, plywood, particleboard, and painted wood release toxic chemicals and arsenic-laden smoke. Stick to clean, split firewood only.
Damper Operation
The damper is the plate inside the flue that controls airflow. Proper operation keeps smoke in the chimney and carbon monoxide out of the house.
- Always open fully before lighting: A closed damper sends smoke into the room within seconds. Double-check by looking up the flue with a flashlight.
- Prime the flue for downdraft: On cold days, the cold air in the flue acts like a plug. Light a rolled newspaper and hold it up the damper opening for 30–60 seconds to reverse the draft before adding wood.
- Keep damper open until ash is cold: Smoldering coals release CO for hours after flames die. Closing the damper too early forces gases into the home.
- Close damper between fires: When the fireplace is cold and clean, close the damper to prevent heated room air from escaping up the chimney.
- Test the handle before each use: Corroded or stuck dampers are common in older homes. If it will not move, call a chimney sweep rather than forcing it.
Safe Ash Disposal
Ash can retain enough heat to start a fire up to four days after the last flame. Every year homes burn down because of careless ash disposal.
Wait at least 48 hours before moving
Even when ash looks cold and gray, live embers can be buried inches deep. The 48-hour rule is a minimum; 72–96 hours is safer after a long burn.
Use a metal container with a tight lid
Never a paper bag, cardboard box, or plastic trash can. Galvanized steel ash buckets are purpose-built, cost $25, and have tight-fitting lids that starve embers of oxygen.
Store outdoors on a non-combustible surface
Place the bucket on concrete, stone, or bare dirt at least 10 feet from the house, deck, or any combustible material. Never on a wood deck or near siding.
Carbon Monoxide Risk and Supervision
CO from a fireplace is invisible, odorless, and deadly at low concentrations. Always treat a live fire as something that requires active supervision.
- Install CO detectors on every floor: Especially within 15 feet of every bedroom. Test monthly and replace batteries twice yearly. Units expire after 7–10 years.
- Never run exhaust fans during a fire: Range hoods, bathroom fans, and dryers create negative pressure that can reverse the chimney's draft and pull smoke into the room.
- Know the symptoms: Headache, dizziness, nausea, confusion, and drowsiness. If multiple people feel unwell simultaneously, evacuate and call 911.
- Never leave a fire unattended: Not to answer the door, not to put kids to bed, not overnight. If you need to leave, extinguish it or keep an adult in the room.
- Use a sturdy screen or glass doors: Screens block sparks that pop out of the fire. Glass doors should only close when flames have died; closing early can crack the glass.
Pro Tips
- •Schedule your chimney sweep in early fall: Prices are lower and appointments are available before winter rush. Every burning chimney should be inspected and cleaned annually.
- •Try the top-down fire method: Stack large logs on bottom, medium on top, kindling and paper on the very top. Lights clean, burns hot, and produces far less creosote than bottom-up fires.
- •Keep a fire extinguisher within 10 feet: A 5-pound ABC dry-chemical extinguisher handles wood, paper, and electrical fires. Check the pressure gauge every few months.
- •Install a chimney cap with spark arrestor: Stops embers from landing on your roof and keeps animals, rain, and leaves out of the flue. A $75–$150 part that prevents enormous problems.
Frequently Asked Questions
How do I know if my firewood is seasoned enough?
Properly seasoned wood should feel light, have visible checking (cracks) on the ends, and make a hollow sound when two pieces are struck together. A moisture meter is the definitive test—readings should be below 20% moisture content. Green wood weighs 40–50% more, has tight bark, and sizzles when burned. Hardwoods like oak need 12–18 months of drying; softer woods like pine need 6–9 months.
Should I have my chimney inspected every year?
Yes. The National Fire Protection Association recommends annual inspection and cleaning for all chimneys, regardless of use frequency. Creosote builds up even with seasoned wood and can ignite at 451°F. A single chimney fire can damage the flue liner and create hazardous conditions for every subsequent fire. Inspections cost $80–$150 and cleanings $150–$300—much less than the $5,000+ repair after a chimney fire.
What causes carbon monoxide from a fireplace?
Carbon monoxide accumulates when combustion gases cannot escape up the flue. Common causes include a closed or partially closed damper, a blocked chimney (nests, debris), downdraft from competing appliances or exhaust fans, and incomplete combustion from wet wood. Every home with a fireplace needs working CO detectors on every floor, especially near bedrooms. CO is colorless and odorless; detectors are your only warning.
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