Fuel
Kiln-dried vs seasoned logs: which should you burn?
Updated 19 October 2026
Short answer: what matters is not the label but the moisture. A log at 20% moisture or less burns hot and clean whether it got there in a kiln or in a log store. A log above that tars your flue, blackens the glass and wastes heat, whatever the bag says. Kiln-dried logs are simply the most reliable way to buy wood that is already dry.
What the words mean
- Green or freshly felled — just cut. Often around half water by weight. Not fit to burn.
- Seasoned — split and left to air-dry, usually stacked under cover with air moving through it. Hardwood typically needs a year or two to get below 20%, depending on the species, how small it is split and how well it is stored. “Seasoned” on its own is not a guarantee of anything.
- Kiln-dried — dried in a heated kiln over days rather than months, to a target moisture level. Good sellers quote the figure, and many aim well under 20%.
- Ready to Burn — a certification scheme. In England, wood sold in units under 2 m³ (bags, nets, small crates) must be certified Ready to Burn, which means 20% moisture or less. More on our Ready to Burn page.
Kiln-dried vs seasoned at a glance
| Kiln-dried | Air-seasoned (bought) | Self-seasoned | |
|---|---|---|---|
| Moisture | Usually quoted, often well under 20% | Varies a lot; check it | Depends on your storage and time |
| Ready to burn | On delivery | Sometimes; may need more time | After a year or more, typically |
| Price | Usually the dearest per load | Usually cheaper | Cheapest, if you have the wood and space |
| Main risk | Getting damp again in poor storage | Sold “seasoned” but still wet | Burning it before it is ready |
Cheap wet wood is a false saving. A big share of the fire’s energy goes into boiling water off, so you burn more logs for less heat, and the cool, wet smoke condenses in the flue as creosote. That means more sweeping and a higher chimney fire risk.
How to check your logs are dry
- Buy a basic moisture meter. They are cheap and last for years.
- Take a log from the middle of the pile, not the top.
- Split it and test the freshly split face, across the grain, not the dry outside.
- Look for 20% or less. Around 15% or under is very good.
Without a meter, dry logs are lighter for their size, often have cracks (checking) in the ends, sound hollow when knocked together and catch quickly. Wet logs hiss, steam and smoulder. These are rough signs; the meter is the real test.
Storing logs so they stay dry
- Keep them off the ground on a rack or pallet.
- Cover the top, but leave the sides open so air can move through. A tarp wrapped tight traps damp.
- Stack bark-side up, in a sunny, breezy spot if you can.
- Bring a day or two’s worth indoors before you burn it so it is at room temperature.
- Kiln-dried wood can pick moisture back up if it sits in the rain, so give it the same care as seasoned.
Buying kiln-dried logs
If you do not have the space or the time to season your own, kiln-dried logs delivered in a bag or crate take the guesswork out. Look for the Ready to Burn logo on smaller loads and a stated moisture figure, and still test a split log when they arrive.
Buy Ready to Burn kiln-dried logs from LogsOnline (affiliate link — we may earn a commission if you buy).
What it means for your chimney
Dry fuel does not replace sweeping, but it does slow the build-up. For wood, most guidance is at least once a year, more with heavy use (see how often to sweep). If you have been burning wet wood, tell your sweep, and look out for the warning signs on our creosote page. Keep your sweep’s certificate: insurers may ask for it (see insurance certificate), and keep a working CO alarm in any room with a stove.
Working out how much to order? See how many logs you need for winter, including loose vs stacked volume and bulk bag sizes.
Lighting up for the season? Run through the first fire checklist, and book early, because diaries fill fast from October (silly season).
Need a sweep?
Find a registered sweep listed from public registers. Ask for a certificate with the date and the sweep’s registration body on it.
Disclosure: some product links are affiliate / referral links. We may earn a commission at no extra cost to you. Not affiliated with HETAS, NACS, the Guild, APICS, Sweep Safe or Ready to Burn / Woodsure. This is general guidance; follow your stove maker’s manual and your sweep’s advice. In an emergency, call 999.