Some are obvious, like plastic, but others might surprise you. From Christmas trees to dryer lint, here are materials you should never burn.
17 Things You Should Never Burn in Your Fireplace
Updated on Feb. 09, 2025
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Treated or Painted Wood
Painted wood and lumber that are treated to resist rot and pests can release toxic chemicals when burned. This includes pallets and leftover construction materials.
“These chemicals can also be more corrosive to your firebox and chimney flue, leading to damage,” says Dan Morris, founder of FireandSaw.com.
Is burning treated or painted wood in the fireplace dangerous?
Yes, it is dangerous. Numerous chemicals can be released from burning these, including arsenic and lead, which can cause health problems ranging from irritated lungs, eyes and skin to cancer and other diseases.
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Furniture
Furniture is often treated and painted, automatically putting it on the no-burn list. But it can also contain nails and screws that can cause cuts and punctures while you’re breaking it apart, feeding the fire and cleaning out the ashes.
Is burning furniture in the fireplace dangerous?
Yes. “Furniture is a mix of different wooden materials and sometimes you don’t even know exactly what it contains,” says Nikolin. “Burning it releases a mix of chemicals and toxins, posing a dramatic risk to your health.”
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Particle Board
While particle board falls under the same categories as treated wood and furniture for what not to burn in your fireplace, it’s getting a separate mention here because “burning particle board is an especially bad idea,” says Nikolin. “It is full of adhesives and chemicals that release harmful toxins when burned.”
Is burning particle board in the fireplace dangerous?
Yes, burning particle board is dangerous. It releases many chemicals that can cause short and long-term health problems.
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Moldy or Rotting Wood
Burning moldy or decaying wood releases spores into the air, which can trigger respiratory issues. It’s also less dense and more moist than proper firewood, which means it won’t produce as much heat but will smoke a lot. Plus, there’s an environmental ethic component to collecting this wood, as dead trees and downed logs are often habitats used by nesting birds and other animals.
Is burning moldy or rotten wood in the fireplace dangerous?
Burning moldy or rotting wood can be a little dangerous, as it could contain fungi and bacteria that irritate your eyes and throat.
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Wet Wood
Wood with high moisture content, aka trees that have been recently cut and not properly seasoned, will smoke excessively, in turn causing dangerous creosote buildup on the walls of your chimney. It’s also aggravatingly difficult to light (which is also a reason why you should never cut down a tree at a campsite).
Is burning wet wood in the fireplace dangerous?
Yes, burning wet wood is dangerous. “Wet or green wood produces excessive smoke and creosote buildup, which is a fire hazard,” says Glenn Gault, CEO of Gault Heating & Cooling.
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Driftwood
This one almost always surprises people, and for me personally, it has caused a couple of arguments while beach camping. Ocean driftwood contains salt, so burning it releases chlorine gas and dioxins, which are bad for your health and corrosive to your chimney.
Is burning driftwood in the fireplace dangerous?
Yes. The fumes from driftwood are carcinogenic. While all wood contains some dioxins, they are much more concentrated in ocean driftwood.
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Newspaper and Cardboard
It’s almost irresistible to toss that old pizza box or Sunday paper in the fire, but these materials can create long-lasting embers that float up the chimney, potentially causing a chimney, roof or wildfire. One exception: it’s generally considered okay to use a small bit of tightly twisted newspaper to start a fire.
Is burning paper and cardboard in the fireplace dangerous?
Yes. Especially in large quantities, products containing wood pulp tend to flake off as large embers, which can start a house fire.
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Glossy Paper
Similar to burning newspaper and cardboard, glossy papers like magazines, wrapping paper, candy wrappers, and chocolate boxes can also cause house fires. Plus, paper with colored inks releases toxic gasses when burned.
Is burning glossy paper in the fireplace dangerous?
Yes. “They seem to be made of paper, but they contain a mix of plastic, glossy or colored inks and foil, which produce a lot of smoke and ash that might clog your chimney, and toxic chemicals that are harmful to your health,” says Nikolin.
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Plastics and Synthetic Materials
You surely know this already, but never, ever, ever burn plastics. They are packed with carcinogens, which get unleashed onto yourself and anyone else who catches a whiff of the smoke when burned, even people far downwind.
It doesn’t matter what type of plastic you have—plastic bags, bubble wrap, plastic bottles, styrofoam, cigarette butts—never throw it in the fireplace. Also, remember that even some to-go food containers that appear to be paper are lined with a thin plastic coating.
Is burning plastic and other synthetic materials in the fireplace dangerous?
Yes, extremely. When burned, they contain chemicals that are dangerous to inhale, many of which are carcinogenic.
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Dryer Lint
I had long hailed dryer lint for its fire-starting prowess, so I was particularly disappointed when I found out that it’s not something to burn in your fireplace, or anywhere, for that matter. One reason is that it contains microplastics from clothing—polyester and nylon are forms of plastic, and more than two-thirds of our clothing is made from those two materials. Also, because dryer lint is super combustible, it can be hazardous to light.
Is burning dryer lint in the fireplace dangerous?
Yes. The synthetic fibers in dryer lint can release dangerous chemical fumes into your home and chimney.
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Charcoal
It seems like a no-brainer to burn some charcoal from the barbecue grill in the fireplace, but doing so releases carbon monoxide, which is not something you want inside your home. Even if your fireplace has good ventilation, there’s a chance your home air filters won’t be able to keep up with the excess amounts emitted from charcoal.
Is burning charcoal in the fireplace dangerous? Yes. Burning charcoal releases particularly high levels of carbon monoxide, a deadly gas that is odorless and colorless and therefore, you won’t know you’re being exposed to it.
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Some Plants
Dried-up plants seem kind of like firewood, and especially after the holidays, it seems easy to dispose of decorations like holly, mistletoe, eucalyptus and dried magnolia leaves in the fireplace. But many of these plants can cause an allergic reaction when their fumes are inhaled, plus can create flare-ups and thick smoke, says Nikolin.
Is burning plants in the fireplace dangerous?
It can be, depending on the plant. “Do not burn invasive plants or vines, such as poison ivy, poison oak or sumac, even when dried, as they release oils that irritate the lungs and skin,” says Gault. Oleander smoke is also particularly dangerous to breathe.
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Christmas Trees
It seems logical to get rid of your old Christmas tree in the fireplace, but please don’t. Not only is the wood not properly seasoned, but evergreen trees and their needles contain high levels of quick-burning resin, which can reach high temperatures and result in a chimney fire or even crack your chimney.
Is burning Christmas trees in the fireplace dangerous?
Yes, they can cause house fires. “The needles can pop and spark, sending embers flying, and they burn quickly and unevenly, often causing flare-ups in the fireplace,” says Nikolin.
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Leftover Food
Leftover food is not as harmless as it might seem, says Nikolin. “First of all, it smells terrible when it burns,” he says. “Just as crucially, the smell of leftover food burning spreads widely around your property and attracts pests, especially rodents, to your home.” Food residue can also stick to your chimney and become an entry point for mice and rats.
Is burning leftover food in the fireplace dangerous?
Burning food in your fireplace is not dangerous, but it can smell bad and attract pests.
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Scented Candles
While they add cheer to other places in your home, refrain from burning scented candles in your fireplace. That’s because they contain synthetic fragrances and dyes that release toxins. The melted wax can also coat your fireplace or chimney, causing clogs, poor ventilation and inefficient burning over time, says Nikolin.
Is it dangerous to burn scented candles in the fireplace?
A little. They release volatile organic compounds (VOCs) which can create a range of health problems, including aggravating asthma.
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Old Photographs
Tempted to cleanse the slate by tossing all of those photos of your ex into the fire like they do in the movies? Don’t do it, says Nikolin. “First of all, older photographs are coated with chemicals and plastics that release harmful fumes when burned,” he says. “Secondly, in nine out of 10 cases, people regret getting rid of old photographs they can’t ever get back.”
Is it dangerous to burn old photographs in the fireplace?
Yes, similarly to other treated papers, they contain plastics and chemical coatings that create toxic fumes when burned.
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Fire Accelerants
Are you frustrated by the time it takes to start a fire? While it might seem like an easy shortcut to use accelerants like gasoline, grill lighter fluid or kerosene, these highly flammable liquids can cause a fire to quickly get out of control and become too hot for your fireplace and chimney.
Is it dangerous to burn fire accelerants in the fireplace? Yes, they can quickly cause a fire to burn out of control, jeopardizing your home and the integrity of your chimney.
About the Experts
- Sergey Nikolin is president of Product Air Heating & Cooling in Washington state, which he established with his brother in 2019 by drawing on his extensive experience in HVAC, indoor air quality and electrical systems.
- Glenn Gault is the CEO of Gault Heating & Cooling, a family-owned business established in 1955 by his father. Gault loves sharing his expertise with homeowners, and has been featured in many popular publications.
- Dan Morris founded FireandSaw.com, where he shares expert insights on everything firewood, wood stoves and chainsaws.
