How much firewood do you need this winter?
Enter your home, your climate, your stove and your wood. You get the number of cords (or cubic metres) to stack, how big that pile is, and what a season of wood heat costs next to gas, oil, propane and a heat pump.
How this firewood calculator works
Most firewood calculators ask how big your house is and guess. This one estimates how much heat your home loses over a winter, then works out how much wood your stove has to burn to replace it.
Heating degree days measure how cold your winter is: the colder and longer it is, the higher the number. Minneapolis sees around 7,500 °F-days, Chicago around 6,200, Atlanta about 2,700. In Europe, Brussels and London sit near 2,700 °C-days and Oslo near 4,000.
The heat-loss factor is how many BTU the house loses per square foot for each degree day. A tight modern house loses about 3–4, an average one 5–6, an older drafty house 8 or more.
Stove efficiency is the share of the wood’s energy that ends up in your room. An open fireplace sends about 90% up the chimney. That is why the same house can need three cords with a modern stove and twenty with a fireplace.
Firewood BTU chart by species
Heat per full cord at about 20% moisture. Dense hardwoods hold almost twice the heat of light softwoods, so one cord of oak replaces nearly two cords of white pine.
| Species | Million BTU / cord | kWh / m³ stacked |
|---|
Cord, face cord, rick and stère
Firewood sellers use units that sound alike but are not.
- Full cord: a tightly stacked pile 4 ft high, 4 ft deep and 8 ft long, or 128 cubic feet (3.62 m³). This is the legal unit in most US states.
- Face cord (also rick): 4 ft high and 8 ft long, but only one log deep. With 16-inch logs that is a third of a full cord. Always ask how long the logs are.
- Stère: one cubic metre of stacked 1-metre logs, used in France, Belgium and much of Europe. Logs cut to 33 cm settle closer, so one stère becomes about 0.7–0.8 m³ once cut.
- Loose (thrown) volume: wood tipped into a trailer or bag takes up about 40–50% more space than the same wood stacked.
Why moisture matters more than species
Fresh-cut wood can be 45% water by weight. Your stove has to boil that water off before the wood gives you heat, and the steam cools the fire and coats the chimney with creosote. Wood at 20% moisture or less burns hot and clean. Split it, stack it off the ground with the top covered, and let it dry for at least one summer (oak usually needs two). A moisture meter pressed into a freshly split face tells you where you stand in seconds.
Frequently asked questions
How many cords of wood does it take to heat a house for a winter?
A 2,000 sq ft house with average insulation in a cold northern climate burns about 3.5–4.5 cords of seasoned hardwood when a modern stove is the main heat source. A mild climate or a well-insulated house can need half of that. A drafty house with an older stove can need twice as much.
How much firewood do I need for occasional fires?
If you light the stove a few evenings a week for comfort, half a cord to one cord usually covers the season. With an open fireplace you burn through it faster but get far less heat.
How long does a cord of wood last?
With a modern stove as the main heat source in a cold month, a typical house burns roughly one cord every four to six weeks. Used only in the evenings, one cord can last the whole winter.
How much should a cord of firewood cost?
In the US, seasoned hardwood usually costs $250–$450 per full cord delivered, more in cities and in the Northeast. In Belgium, the Netherlands and France, a stère of dry hardwood typically costs €80–€130.
Should I buy extra wood?
Yes. Winters vary by 15–25% from year to year, so stack about 20% more than the calculator’s average figure. Dry wood keeps for years under cover, so leftovers are not wasted.
Is heating with wood cheaper than gas?
It depends on what you pay for wood and on your stove. If you cut your own wood or buy it under about $200 per cord, wood usually beats gas and oil. At $400 per cord with an older stove it often costs more. The comparison above uses your own prices.