Everyday
Wood Stove Size Calculator
Enter your floor area, climate band and house details, and the page works out the heat output your stove needs, the size class to shop, how many cords you will burn in a season, and what that firewood costs.
How it works
Behind the numbers
The load starts with a climate band figure per square foot at 8-foot ceilings and average insulation: 25 BTU in mild climates, 35 in moderate ones, 45 in cold ones and 55 in very cold ones. Ceiling height scales it, and insulation, windows and air leakage each adjust it up or down. The multipliers are: insulation good ×0.85, average ×1.00, poor ×1.20; windows few, modern double-pane ×0.95, average ×1.00, many, old single-pane ×1.10; air leakage tight ×0.95, average ×1.00, drafty ×1.10; ceiling height scales by height ÷ 8. A 1,500 square foot home in a moderate climate with average everything needs about 52,500 BTU per hour. That is a planning estimate in the same family as the sizing charts stove dealers publish; a heat-loss calculation on your actual house is the number to buy on.
Stove classes follow the required output. 40,000 BTU per hour or less is a small stove, over 40,000 to 65,000 is medium, and above that is large. Check the class against the manufacturer's square-foot rating as well, since a long open floor plan heats differently from the same area cut into small rooms. Above 80,000 BTU per hour, one stove rarely covers the house, and the page says so rather than rounding up to a stove that cannot do the job.
Seasonal firewood comes from equivalent full-load hours, which run 800 in mild climates up to 1,800 in very cold ones. Multiply the load by those hours for the season's heat, then divide by your stove efficiency times 20 million BTU per cord of seasoned hardwood. A 1,500 square foot moderate-climate home at 75 percent efficiency works out to about 4.2 cords a season. Wet wood, short burns and an oversized stove all push that number up, which is why the efficiency and cord price are editable.
FAQ
Questions, answered
What size wood stove do I need for 1,500 square feet?
In a moderate climate with average insulation, about 52,500 BTU per hour, which is a medium stove. The same house in a cold climate needs closer to 67,500 BTU per hour and a large stove, while a mild climate with good insulation drops to around 32,000 BTU per hour and a small one. Climate and insulation move the answer more than floor area alone.
How many cords of wood will I burn in a season?
A 1,500 square foot home in a moderate climate at 75 percent stove efficiency burns about 4.2 cords of seasoned hardwood a season. Cold climates and drafty houses push that toward 9 cords for a 2,000 square foot home. The page estimates it from your load, your climate band's full-load hours, and the efficiency you enter.
Can one wood stove heat a whole house?
Up to about 80,000 BTU per hour, usually yes, if the floor plan is open enough for warm air to reach the far rooms. Above that, most homes need a second stove, a furnace backup, or a stove zoned to the main living area. Stove placement matters as much as size: a stove at the far end of a closed-off house leaves the bedrooms cold no matter how big it is.
What does EPA certified mean for a wood stove?
Stoves built since 2020 must meet the EPA limit of 2.0 grams of particles per hour. Certified stoves also burn cleaner and hotter than old uncertified ones, which is part of why they run 63 to 80 percent efficient on seasoned wood. Some areas restrict uncertified stoves, so check local rules before buying a used one.
How far does a wood stove need to be from the wall?
Unlisted stoves need 36 inches to combustibles under NFPA 211. A listed stove follows its own label, which is usually 12 to 18 inches, and a listed heat shield can cut that further. The label on the stove you buy is the authority; the page flags this because clearance, not BTU, is the most common reason an install gets redone.