Most wood-heat problems trace back to wet wood. Freshly cut wood can be half water by weight, and that water has to boil off before the wood will burn cleanly. Seasoning is simply the process of letting it dry to the point where a fire burns hot instead of smouldering. Get this right and chimney maintenance gets easier; get it wrong and creosote builds quickly.
Moisture matters more than species
Burning wet wood wastes energy boiling off water, lowers the flue temperature, and pushes unburned tar up the chimney as creosote. Well-seasoned firewood is generally considered to be below about 20% moisture content. Below that threshold, the wood lights readily, burns hotter, and produces noticeably less smoke. The species you burn affects density and heat output, but a dense hardwood that is still wet will perform worse than a lighter wood that is properly dry.
Reading a moisture meter. Split a representative piece and press the pins into the freshly exposed inner face, not the weathered outside. The outside of a log can read dry while the core is still wet. Take a few readings and judge by the wettest.
Drying times for common Canadian species
Drying time depends on species density, how the wood is split and stacked, and the local climate. Denser hardwoods hold water longer than softwoods. The figures below are general expectations for split wood stacked off the ground in a sunny, breezy spot; confirm with a moisture meter rather than the calendar alone.
| Wood | Type | General drying expectation |
|---|---|---|
| Sugar maple, oak, ash | Dense hardwood | Longer — often a year or more |
| Birch, beech | Hardwood | Moderate to long |
| Poplar, aspen | Soft hardwood | Shorter |
| Spruce, pine, fir | Softwood | Shorter, but lower heat per volume |
Ash is sometimes singled out as drying faster than other hardwoods, and birch as drying reasonably well if the bark is split so it does not seal in moisture. Even so, planning a full season ahead is the safe approach for dense species.
How to stack so air does the work
Seasoning is mostly about airflow and sun. The way a cord is stacked has as much effect as time.
- Split the wood — smaller faces dry far faster than whole rounds.
- Raise the stack off the ground on rails or pallets so it does not wick up ground moisture.
- Leave gaps between rows and pieces so air can move through.
- Put the stack where it gets sun and prevailing wind, not in a damp corner.
- Cover only the top, leaving the sides open; a fully wrapped pile traps moisture.
A note on the cord
Firewood in Canada is commonly sold by the cord, a stacked volume of 128 cubic feet — the familiar 4 ft by 4 ft by 8 ft pile. "Face cords" and "bush cords" are sold too and mean different amounts, so it is worth confirming exactly what a quoted price covers before buying.
Telltale signs of dry wood
- Checks — radial cracks — have opened across the cut ends.
- The wood is noticeably lighter than when it was green.
- Two pieces knocked together make a sharp, hollow clack rather than a dull thud.
- A moisture meter on a fresh split face reads below about 20%.
Local consideration. Many parts of Canada restrict moving firewood to limit the spread of pests such as the emerald ash borer. Buying or burning wood close to where it was cut is the cautious approach; check current provincial guidance before transporting wood long distances.
Related notes
Dry fuel is the first defence against the buildup covered in the creosote removal guide, and clean burning is part of what an inspector looks for in the chimney inspection guide.
Sources: Natural Resources Canada, CSIA, and WETT Inc. Confirm local firewood-movement rules with your provincial authority.