Find out exactly how many cords of firewood you need to heat your home all winter. Enter your house size, climate zone, wood species, and stove type — and get cords, face cords, storage space, and cost in seconds.
A full cord is a standardized unit of stacked firewood measuring 4 feet wide × 4 feet tall × 8 feet long, for a total of 128 cubic feet of stacked wood. That's the only legally recognized cord measurement in most U.S. states. However, because wood logs stack with air gaps between them, the actual solid wood volume in a cord is closer to 80–90 cubic feet — the rest is air. This is why BTU figures "per cord" vary slightly even for the same species: a tighter stack has more actual wood and more BTU.
A face cord (also called a rick or a third of a cord) is the same 4×8 foot face but only one log-length deep — typically 16 inches, which is the standard firebox length for most stoves and inserts. A face cord is exactly one-third of a full cord. When someone advertises "a cord" at a suspiciously low price, ask whether they mean a full cord or a face cord — the difference is 3x the wood.
A rick is a regional term used mostly in the South and Midwest. It typically means a face cord (4×8×16 inches) but can vary — always ask the seller to give you dimensions before you pay.
When you buy firewood, you're paying for stacked volume. Always measure the stack yourself after delivery: width × height × depth in feet, divided by 128, gives you the fraction of a full cord you received. A 4×4×8 pile is one cord. A 4×4×4 pile is half a cord. Never pay for a "truckload" without measuring — pickup truck beds range from 50 to 100 cubic feet, which might be a half cord to nearly a cord depending on the truck and how high it's stacked.
The confusion between face cord, full cord, and rick is responsible for more firewood disputes than anything else. Here's the definitive breakdown:
Most home stoves and fireplace inserts use 16-inch logs, so your firebox holds exactly one face cord's worth of depth. When planning storage, think in face cords for daily use and full cords for purchasing and annual planning.
The best firewood in any region is the hardwood that grows most abundantly there — because it's cheapest, freshest, and best seasoned locally. That said, BTU output per cord varies significantly between species.
Northeast and New England: Sugar maple and yellow birch are the standard benchmarks — both dense, high-BTU hardwoods that season in one summer if split properly. White and red oak are also widely available and among the highest-BTU species, but they need at least a full year to season due to their density. Ash has long been prized because it seasons faster than oak (6–8 months) while still delivering solid BTU output. Avoid cherry and poplar as primary heat sources — they're low density and burn fast.
Midwest: Osage orange (hedge apple) is the undisputed BTU king if you can find it — it burns so hot it can warp stoves. For mainstream use, bur oak and white ash are the standards. Elm is available but difficult to split and burns mediocre. Cottonwood and silver maple are soft, low-BTU, and best avoided for heating.
South: Live oak is extremely dense and high-BTU but very hard to split and slow to season. Red oak and white oak are more manageable. In pine-heavy regions, longleaf pine is denser and higher-BTU than other pines but creates more creosote — clean your chimney more frequently if burning pine.
Pacific Northwest: Douglas fir is the most common heating wood and is actually reasonably efficient for a softwood — about 20M BTU/cord when seasoned. Avoid alder and cottonwood for primary heating; they're too low-density. If you're in an area with red alder as the main available species, plan for 30–40% more cords than this calculator suggests for equivalent heat output.
Mountain West: Ponderosa pine and lodgepole pine are common but softwood-class BTU. Aspen is extremely common but one of the lowest-BTU woods available — count on needing 50–60% more aspen than you would need of oak. Pinon pine burns hot and smells great but is expensive and creates more creosote than hardwood.
Properly seasoned firewood is the single biggest variable in actual heat output. A green oak log and a seasoned oak log contain the same total energy — but the green log uses a large fraction of that energy evaporating its own moisture rather than heating your home. Green wood can contain 50–60% moisture by weight. Seasoned wood typically runs 15–20%. The difference in usable heat output can be 25–35%.
When to split: Split immediately after cutting. A round log dries from the ends only; a split piece exposes the interior grain and dries far faster. Small splits (4–5 inches across) dry in one season. Large rounds can take 2–3 years and still have wet centers.
How to stack: Bark-side up on the top row to shed rain. Stack off the ground on pallets, 2x4s, or a purpose-built rack — ground contact traps moisture and invites rot and insects. Leave space between rows for air circulation — don't stack against a barn wall with no airflow behind the pile. A roofed shelter is ideal; a simple tarp over the top is adequate if you leave the sides open.
How long to season: Dense hardwoods like oak and hickory need 12–18 months of proper outdoor drying after splitting. Ash and maple need 6–12 months. Softwoods like pine and fir can season in 6 months if split small and stacked in a dry, sunny location. If your wood hisses when it burns, smokes excessively, or leaves heavy creosote deposits on your chimney glass, it's too wet.
How to test moisture: A moisture meter (under $20 at any hardware store) takes the guesswork out. Split a fresh piece and test the interior. Below 20% is good. Below 15% is excellent. Above 25% and you'll significantly underperform the BTU figures in this calculator.
Order in spring for next winter — this is the single most important piece of advice for anyone heating with wood. Here's why: in spring, wood dealers have just cut their winter inventory and the wood is still green. It needs 6–12+ months to season. If you order in October for a November start date, you're getting green wood, paying fall prices (which are typically 20–40% higher than spring prices), and competing with everyone else who also procrastinated.
The optimal sequence: order in March or April, accept delivery of green or freshly split wood, stack it correctly, and let it season through the summer and fall. By October it's ready, and you paid spring prices — often $50–100 per cord less than fall prices in most markets.
If you're cutting your own wood, the same timing applies. Cut and split in late winter or early spring so the wood has the maximum drying time before the heating season. Wood cut in March and stacked in a sunny, breezy location is reliably seasoned by October in most of the country.
Buy more than you think you need. A cord buffer beyond your estimate gives you insurance against a longer-than-expected winter, wet wood, or a stove that runs more than planned. Seasoned wood stores indefinitely under a proper roof — any leftovers roll into next year and are exceptionally well-seasoned for it.
The range is enormous because it depends on house size, insulation quality, climate, stove efficiency, and how comfortable you keep the house. A well-insulated 1,200 sq ft home in the Midwest (roughly 6,000 HDD) using a modern EPA-certified wood stove as the primary heat source typically burns 3–5 full cords per season. The same house in New England's cold interior might burn 5–7 cords. A poorly insulated older farmhouse in a cold climate with an open fireplace might burn 10–15 cords — most of which goes up the chimney rather than heating the room. The biggest single lever on cord consumption is stove efficiency: upgrading from an open fireplace (10% efficient) to a modern insert (75% efficient) can cut your cord consumption by 85% for the same amount of delivered heat.
HDD stands for Heating Degree Days — a measure of how cold your winter is in aggregate. Each day is measured against a baseline of 65°F (the temperature below which most buildings need heating). A day with an average temperature of 30°F contributes 35 HDD (65 − 30). A full winter's HDD total is the sum of every day's contribution. Boston, MA averages about 5,600 HDD per year. Minneapolis averages about 8,400 HDD. Houston averages about 1,600 HDD. A higher HDD number means your house loses more heat over the winter, which directly translates to more firewood needed. This calculator uses HDD as the primary driver of your heat load, which is how professional energy auditors and fuel dealers size heating systems and estimate annual fuel consumption.
For heating purposes, an open masonry fireplace is nearly worthless — it operates at roughly 10% efficiency, meaning 90% of the heat your wood produces goes up the chimney. Worse, when a fireplace is drawing air to feed the fire, it's pulling heated room air out of the house through the chimney, which can actually make the rooms away from the fireplace colder even while the room with the fire feels warm. An open fireplace is excellent for ambiance and worth having for that reason, but it's not a serious heat source. A modern EPA-certified insert dropped into an existing fireplace opening converts that same masonry to 75%+ efficiency and can become a legitimate primary heat source for the zone it's in. The cost of an insert plus installation is typically recovered in fuel savings within 3–5 years if you heat primarily with wood.
Creosote is a tar-like byproduct of incomplete combustion that condenses on the inside of your chimney flue as smoke cools. It's highly flammable — chimney fires caused by creosote buildup are among the leading causes of house fires in wood-burning homes. The primary cause of creosote buildup is burning wet (unseasoned) wood. Wet wood burns at lower temperatures and produces far more smoke and unburned particles that condense on the flue walls. Burning dry, well-seasoned wood in a properly sized stove with adequate air supply dramatically reduces creosote formation. Have your chimney inspected and swept by a certified chimney sweep (CSIA-certified) every year before burning season, or after every two cords of wood burned — whichever comes first. This is not optional safety maintenance.
The cost per million BTU ($/MMBTU) is the correct way to compare heating fuels. To calculate it for any fuel: take the cost of one unit of fuel, divide by the BTU content of that unit, multiply by the efficiency, and scale to per million BTU. As of 2026, well-seasoned oak at $300/cord with a 70% efficient stove delivers heat at roughly $15–16/MMBTU — competitive with or cheaper than most other fuels in most markets, especially if you're cutting and splitting your own wood. Compare this to propane at $2.50/gallon (91,500 BTU/gallon × 95% efficiency = ~$28/MMBTU), heating oil at $3.50/gallon (138,000 BTU/gallon × 87% = ~$29/MMBTU), or resistance electric at $0.14/kWh (3,413 BTU/kWh × 100% = ~$41/MMBTU). A heat pump at 300% efficiency would come in around $14/MMBTU at $0.14/kWh. Wood heat is economically competitive in most of North America, especially in regions where firewood is abundant and local.
One full cord = 128 cubic feet of stacked wood. A standard woodshed or covered rack that measures 8 feet wide × 4 feet tall × 4 feet deep holds exactly one cord. Stack it bark side up, off the ground, with airflow on at least two sides. Plan your storage before you order — running out of covered space forces you to tarp wood on the ground, where it seasons poorly and often rots on the bottom. If you need 5 cords for a season, your storage area needs to accommodate at least 640 cubic feet of stacked wood, plus access room. Two rows of 4×4×8 stacks side by side covers it. Many homesteaders store 1–2 cords on a covered porch near the door as a "working stack" and keep the rest under a shed roof away from the house (to avoid bringing insects indoors).