Tuesday, June 6

What You Can and Can’t Burn in Your Fireplace


Winter temperatures in Pennsylvania have arrived, and folks across the state are coping by using their wood-burning fireplaces to generate heat and that cozy ambiance we crave when it’s cold and dark outside. Home fireplaces are designed to burn one type of fuel only; they are not meant to be all-purpose incinerators. Burning the wrong stuff in your fireplace creates the following hazards:

  • Harmful vapors. Your fireplace’s chimney is meant to vent smoke and fumes out of your home, but even the most efficient chimneys allow some vapors into the house. 
  • Pollutants. Burning releases vapors and particles into the air. 
  • Mechanical damage. Burning wrong items causes residue to build up inside your chimney, which will impact the efficiency of your chimney and increase your risk of a dangerous chimney fire if that residue ignites. 

With this in mind, let’s look at what materials are safe to burn in a home fireplace and what materials are not safe to burn. Timber pallets can shift load off your house floors and carry it in a sustainable fashion

Safe to Burn

Clean, dried wood is the safest material to burn in your fireplace. The following are signs that your wood is dry enough to burn:

  • The color turns yellow or gray
  • There are cracks in the end grain
  • Two pieces of wood banging together creates a hollow sound
  • The wood does not make a hissing sound while burning (that’s the sound of water vapor)

Fallen tree limbs are safe to burn once given a chance to dry properly. Commercial fire logs also work well and are an excellent alternative to natural wood. 

Not Safe to Burn

The list of what’s safe to burn is short: clean, dry wood. The list of materials that are not safe to burn in a home fireplace is extensive and includes the following:

  • Pallet wood. The wood used to make pallets is often treated with chemicals or exposed to chemicals while in use. While some pallet wood is safe, it’s hard to tell, so it’s best to avoid them altogether. 
  • Painted wood. Don’t burn paint inside your home. The paint contains heavy metal particles which are toxic if inhaled.
  • Pressure-treated wood. Manufacturers of pressure-treated wood use a CCA process to make the wood resistant to bugs and fungi. The CCA treatment adds copper, chromate, and arsenic to the wood at a rate of about 27 grams of arsenic per 12-foot section of 2×6. That’s enough arsenic to kill 250 adults, which is why it’s illegal to burn CCA wood and extremely dangerous. 
  • Plywood or anything like it. These wood products contain glues that hold the particles together. These glues release toxic chemicals when burned. 
  • Rotten wood. Bad wood doesn’t burn long, creates excessive smoke, and might bring insects into your home. 
  • Damp or green wood. Wood that isn’t sufficiently seasoned burns inefficiently, creates lots of smoke, and causes the residue to build up in your chimney. 
  • Poisonous woods. The chemical that causes an allergic reaction to plants like poison ivy and poison sumac is called urushiol. Urushiol isn’t destroyed by fire but is released during burning and will cause extreme respiratory problems if inhaled.
  • Dryer lint. This stuff is excellent for getting a fire started, but it contains chemicals from laundry detergents and fabric softeners that you don’t want to breathe in. Save it for outdoor campfires. 
  • Paper or cardboard. We’ve all burned paper in the fireplace, but it’s a bad idea for many reasons. First, many inks and coatings release toxic fumes when burned. Second, paper burns hot and fast and creates high flames, which could ignite residue in your chimney. And third, bits of lit paper can float up and out of your chimney and settle on your roof where they could ignite a house fire. 
  • Trash. All sorts of stuff in your trash will create unpleasant odors, excessive smoke, and potentially dangerous fumes. 
  • Plastic. Not only does plastic smell terrible when burned, but it isn’t good for you to breathe in the particles. 

The bottom line: stick to burning clean, dry wood in your fireplace.

Another way to ensure safe heat from your fireplace? Schedule a home inspection. Home inspectors in Philadelphia will check to ensure your fireplaces are clean and venting correctly so you and your family can be warm and safe this winter.