Oak

Why this fits you

Oak burns around 24-29 million BTU per cord, among the highest of common firewoods, and burns long and steady thanks to its density. The tradeoff is time: oak's dense grain holds moisture stubbornly, and it typically needs a full 1-2 years of proper seasoning before it's dry enough to burn cleanly.

Heat value and burn behaviour

Oak is the benchmark hardwood for heating. Heat content depends on the species, but white oak is roughly 24 to 26 million BTU per cord and red oak somewhat lower, around 21 to 24. It burns slowly and steadily and leaves long-lasting coals, which makes it ideal for overnight burns and for the coldest part of winter. It is not a good kindling wood and does not catch quickly.

Seasoning is the catch

Oak holds a great deal of water, and it dries slowly. Plan on a year at minimum and often two for split wood stacked off the ground in a sunny, windy spot with the top covered. Burned too green, oak hisses, smokes and gives little heat while depositing creosote in the chimney. A moisture meter reading at or below about 20 percent is the practical test, which you can take from a freshly split face.

Splitting, stacking and cost

Straight-grained oak splits fairly well when green and gets harder as it dries, so split it early. Pieces are heavy, which affects how much you can stack and carry. Oak is widely available in much of the eastern and central United States and is often among the more reasonably priced hardwoods, though price varies by region and season.

Cautions

Oak wilt is a disease that kills oak trees, and some states limit moving oak firewood, especially from recently felled trees. Check local rules before transporting wood across county or state lines. Oak firewood also has high tannin content, which can stain a wet surface, so store it off bare concrete.

When to choose something else

If you want wood that is ready to burn within a few months, ash or a softwood will be quicker. If you want the highest density wood available locally, hickory or black locust may beat oak. Choose oak when you can season it well ahead and want reliable, steady heat.

Weight and handling

Seasoned oak is heavy, roughly two tons per cord, which affects how you stack, carry and store it. Build a stack on pallets or rails with space between rows, and keep the top covered but the sides open. If you buy wood, ask whether it was seasoned or green, since green oak weighs more and will not burn well until dried.

How it compares

Buying checklist

• Split and stack at least 12 months before burning, ideally longer
• Cover the top of the stack but leave the sides open to airflow
• Test with a moisture meter -- below 20% is ready to burn

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