Firewood sold as "seasoned" can have moisture content anywhere from 15% to 50%+ depending on the dealer. That range is the difference between a fire that heats your home efficiently and one that smokes, smolders, and slowly coats your chimney in creosote.
What happens when you burn wet wood
Wood burns in two stages. First the moisture evaporates — that requires energy, which comes from the fire itself. Only after the water is gone does the wood actually combust and produce heat. When wood is wet, a significant portion of the fire's energy goes toward driving off that water instead of heating your home.
The result: lower flame temperatures, more smoke, harder to keep lit, and a fraction of the BTU output you'd get from the same volume of dry wood. A cord of properly seasoned oak produces roughly 24 million BTUs. The same cord at 40% moisture content might deliver 60–70% of that.
Creosote: the real danger
Incomplete combustion from wet wood produces a byproduct called creosote — a tar-like substance that condenses and builds up on the inside of your chimney flue. It's flammable. Chimney fires start when a spark ignites creosote deposits, and they can burn hot enough to crack masonry or ignite nearby framing.
The National Fire Protection Association recommends inspecting and cleaning chimneys annually. If you're burning wet wood regularly, you'll accumulate creosote faster than annual cleaning can keep up with.
What "seasoned" actually means
In Connecticut, firewood is legally considered seasoned when it has been cut, split, and dried for at least six months. In practice, six months is a floor — not a guarantee. Dense hardwoods like hickory and sugar maple often need 12–18 months to reach ideal moisture levels. The target for burning is under 20% moisture content.
"Air-dried" doesn't mean the same thing as "ready to burn." Wood can sit outside improperly stacked for a year and still be too wet. The only way to know is to measure.
Signs you received wet wood
- Fire is hard to start and won't stay lit without constant attention
- Lots of visible smoke, even once the fire is going
- Wood hisses or produces a bubbling sound at the cut ends
- Heavy for its size — water is dense
- Ends look fresh and light-colored rather than dark and cracked
- A moisture meter reads above 25%
What to do if your wood is wet
If you've received wood that isn't ready to burn, you have options. If it's close — say, 25–30% moisture — store it stacked with good airflow and it may be burnable in a few months. Stack it bark side up off the ground, in a spot that gets sun and wind. Cover only the top, not the sides.
If the wood is significantly wet (above 35%), contact the dealer. All dealers on CT Firewood Delivery are required to accurately represent the moisture content of their wood. Your delivery invoice includes the wood's species and seasoning information.