Quiz: firewood knowledge
Find out how much you know about firewood
1. True or False?
Three kg of kindling produces less heat than a 3 kg log.
2. True or False?
Newly cut wood contains a natural fire retardant that loses its effectiveness over time.
3. True or False?
Firewood for heating is sold only in full cords—a volume of 4′ by 4′ by 8′ (so clear some space for that colossal pile of wood you’ll be getting).
4. True or False?
A fire in the stove, but no smoke out the chimney, means you’ve left the draft open too wide.
5. True or False?
If you’re heating with wood, burn hardwood, not softwood.
1. False. All other things being equal, both kindling and logs give the same heat output, but kindling burns faster (and then the heat is gone) because it has more surface area. For a slow, all-night-long burn, the denser the wood, the better. That’s why a big log of maple or oak keeps you warm until morning.
2. True. That fire retardant in green wood is water, which reduces the log’s heat output and slows ignition. Buy wood in late winter or spring to give it time to dry, or season, and it will burn well by fall (oak takes a little longer). Seasoned wood trumps the slow, sooty burn of wet wood, because energy isn’t wasted evaporating the water that’s still hanging around.
3. False. Firewood is usually sold in a more convenient, but less precise unit called a face cord or stove cord. You’re still buying a pile that’s 4′ high by 8′ long, but it’s only as deep as one piece (usually between 12″ and 18″). Knowing the average length of a piece lets you calculate and compare a full cord’s cost among suppliers, as well as double-check that the wood will fit your stovebox.
4. False. A plume-free chimney probably indicates a newer, B415- or EPA-certified stove, which burns so cleanly it leaves only a visible heat wave above the flue. Such stoves release only 3 to 4 grams per hour of pollutants—not enough to be visible and squeaky clean compared to old stoves, which give off about 60 g/h.
5. False. Hardwood burns longer and produces more even heat output, but seasoned softwood makes good fuel too. Have both on hand, burning softwood in spring and fall when you need your stove for only a few hours at a time. Keep the hardwood for winter, when you need heat around the clock.
This article was originally published on July 9, 2009