How to select, store and season firewood

It’s never too early to start planning for next winter, and that’s especially true if you heat your home with wood. Although it sometimes seems like a never-ending cycle of splitting, stacking and storing cords of wood, the heat is worth it.

Incidentally, not every log is created equally. There are various factors to consider when selecting, storing and seasoning firewood.

Selection

The first thing to consider when choosing the right wood to burn is whether or not it was cut locally. Firewood cut from a native tree decreases the risk of transporting invasive pests to your property.

The second factor to take into consideration is the density of the wood. Hardwood like birch, maple and oak take longer to season, but provide nearly twice as much heat. Softwoods like spruce, fir and pine can season in half the time, but produce half the heat.

Hardwood

• Cut from trees with leaves
• More dense
• More British thermal units (BTU) per cord
• Burns slower
• Leaves a hardy bed of coals
• Heavier

Softwood

• Comes from trees with needles
• Less dense
• Lower BTUs per cord
• Burns rapidly
• Doesn’t produce a lasting bed of coals
• Lighter

Using low-heat firewoods gives you the benefit of seasoning your wood in about half the time, but will directly affect your heating efficiency. It may require two cords of softwood to produce the same heat as one cord of hardwood, according to the University of Alaska Cooperative Extension. Softwood is better used as kindling to start fires because it splits more easily.

Even if a less dense wood feels heavy before it’s seasoned, it will weigh about half as much as a hardwood variety when both are seasoned. This is because softwoods have a high moisture content when they are green, suggesting they are denser than they actually are.

Although hardwood takes longer to season, is heavier and burns slower, it is your best bet for maximizing heating efficiency.

Seasoning wood

It’s best to cut firewood in the late winter and early spring to allow the wood to dry over the summer months to be ready for the following winter. Wood that hasn’t been seasoned has a higher moisture content. Green wood requires a lot more heat to evaporate the water trapped inside before it can burn and give off heat. Burning wet wood creates a lot of smoke and may cause a dangerous creosote buildup — a blockage that collects on flues and inside chimneys when combustible gases don’t burn in the firebox and condense.

Wood burns best with a moisture content between 10 and 20 percent, which requires about six months of drying for softwood and 12 months of drying for hardwood. Split wood dries faster; however, it’s still important to season wood for the suggested amount of time as freshly cut logs generally have to drop from 80 percent moisture or higher.

Once you’ve seasoned your wood for about a year, you want to make sure its dried to the ideal moisture level. Wood with a moisture level under 10 percent is too dry because the trapped water regulates how fast it will burn. Burning wood that is too dry can damage your stove as the rapid fire creates excessive heat. It’s best to aim for an average moisture level of 20 percent.

How to check the moisture level of wood

1. Use a moisture meter to ensure wood is at or under 20 percent.
2. Lift the wood. Dry wood weighs less.
3. Inspect the ends to look for cracks. Wood cracks as it dries.
4. Knock two pieces together and listen for a hallow sound.
5. If it’s not already, split a piece and check to see if the inside feels dry to the touch.
6. If you’re still unsure after trying the first five steps, burn some test pieces outside. Wet wood is hard to light and smolders.

Storage

Outdoors

The best way to store wood is outside at least 25 feet from your home, off the ground, with the top covered. Stacking wood on pallets is one way to assure good air flow and reduce the risk of insect infestation. You don’t want to treat the wood with pesticides as the chemicals can release toxic fumes when they are burned.

It’s also a good idea to have some sort of ordering system to make sure you’re burning the most seasoned wood first.

You can find plans and a material list for a modular wood shed on the United States Environmental Protection Agency’s website.

Indoors

When you’re storing firewood indoors never try to dry green wood by stacking it close to your stove. Make sure to maintain a three-foot radius between your wood stack and stove at all times.

Don’t burn

You have to be careful what you put in your wood burner. In addition to unseasoned wood, this is the EPA’s list of things you shouldn’t burn:

• Trash — cardboard, plastics, foam and the colored ink on magazines, boxes, and wrappers
• Coated, painted or pressure-treated wood
• Ocean driftwood
• Plywood, particle board or wood with glue on it
• Rotted, diseased or moldy wood
• Plastic, asbestos, rubber, manure and animal remains

If you’ve made it through the final check-off, you’re ready to start preparing for next winter. Enjoy your wood stove!

Related content

• How to prepare your wood burner for winter
• Wood stove/fireplace inspection checklist
• Heating with wood: Three mistakes to avoid
• Firewood basics: Tips for drying, storage and safety

Resources

• United States Environmental Protection Agency
• Alaska Department of Environmental Conservation
• University of Alaska Cooperative Extension
• University of New Hampshire Cooperative Extension