Whether you are an outdoor enthusiast or a regular firewood user, most people often wonder, “how long does firewood burn?.” Getting the answer to this question will let you know how much firewood you need before you light a match. You will also learn how long the fire will last, so there are no unpleasant surprises.
How long your firewood will burn depends on several factors. Typically, the denser the firewood, the longer it will burn. This article will teach you how long firewood burns and which firewood burns the longest.
How To Know If Firewood Is Good Or Bad
Before learning how long firewood burns, you must learn to differentiate good from bad firewood. Below is a quick comparison between good and bad wood.
Good Firewood
The best firewood to burn is well-seasoned wood. Well-seasoned firewood should have a low moisture content (15-20℅). If the moisture level exceeds 25%, the wood will not make a good fire.
Good firewood usually has darker ends and visible cracks and splits. It is dry; it should not appear wet or fresh, like green or freshly cut wood. Due to the low moisture content, well-seasoned wood is usually light, unlike green or rotten wood.
Good firewood usually has a dry, earthy smell. When hit together, it should produce a loud “chunk” sound, not a low “thud” sound like rotten or green wood.
Well-seasoned Stumps of Wood
Bad Firewood
Generally, bad firewood is any firewood that is not suitable for burning. Rotten firewood or freshly-cut wood (green wood) falls into this category. Rotten wood is firewood that has decomposed due to water and moisture. Green wood, on the other hand, refers to freshly cut wood.
Both types of wood are bad because they contain high moisture. Green lumber usually has a moisture content of 40-50℅. Burning much of it in your wood stove or fireplace could lead to creosote build-up.
You can tell that your firewood is rotting by feeling the edges. If it feels soft around the edges, then it has begun to decompose. If the firewood looks like soil and feels crumbly, it is completely rotten. Other factors to look out for include discoloration, a cruddy smell and fungi or mould growth.
The table below makes it simple;
| Good Firewood | Bad Firewood |
| Its moisture level is at or lower than 20℅ | Its moisture level is greater than 25% |
| Smells dry and earthy | It smells muddy and cruddy |
| It is firm and dry to the touch | It is wet and crumbly to the touch |
| It is free from fungus or mold growth | It is discolored; has fungus and mold growth |
| It gives a ringing “chunk” sound when hit together | Produces a hollow “thud” sound when hit together |
What Factors Affect How Long Firewood Burns?
Burning Firewood Outdoors
Several factors affect how long each firewood will last. Factors such as the wood species, moisture content, and even weather conditions will impact the burn time.
Below are the factors that will dictate how long your firewood will last.
Species of Wood
As you may have guessed, the wood species that you use for fire plays a significant role in the burn time. Generally, hardwoods like oak, hickory, or ash burn longer than softwood like pine or fir. The reason is that hardwood is denser and usually has a higher BTU (British Thermal Unit) than softwood.
Moisture Content
The moisture content of your wood will also determine how well and how long it burns. Well-seasoned wood with low moisture content will typically burn hotter than green wood. However, green wood will burn for longer but produce negligible heat.
Level of Decay
Decay sets in the minute you cut down wood from the rest of a tree. However, if you ensure to season your wood correctly, it can last for as long as ten years. If your wood becomes rotten due to moisture exposure, it will not make a good fire.
Weather Conditions
The weather conditions and climate of your area also affect how long firewood lasts. If you live in high humidity or higher altitude areas, your fire will struggle due to the lack of oxygen.
Fire Size
The fire size is another crucial factor to consider. For instance, a small chimney fire will not outlast a big outdoor bonfire.
Wood Cut
The woodcut and size are equally important. Thickly-cut wood will last longer than a thinly-cut wood
Which Firewood Burns For The Longest Time?
An Oak Tree
There is no “one size fits all” answer regarding which wood burns the longest. Several factors, like humidity and density, can affect burn time. However, this list you are about to read will give you a general idea of which firewood burns the longest.
Oak
One of the best and most readily available firewood for burning is oak. It produces a lot of heat. Also, it does not create sparks or creosote. It has a BTU of about 27 million per cord of wood (128 cubic feet) and can burn for 5-8 hours.
Maple
Like oak, maple is suitable for making long-lasting fires and is easy to find. Unlike oak, however, maple has a lower BTU of 25 million per cord, meaning it burns less hot. Typically, it burns for 5-7 hours.
Ash
Ash, depending on whether it is green or white ash, has a BTU of 20-24 million. Hence, it burns like maple. However, it lasts as long as the oak: 6-8 hours.
Hickory
Hickory bests oak when it comes to burning time. It has a BTU of 28 million per cord; hence, it burns longer and hotter than oak. However, it is not as readily available and is more challenging to split.
Cherry
Cherry burns on average for 5-7 hours because it has a low BTU of 20 million per cord. It is as dense as oak. However, it does not burn as hot or for as long. Cherry seasons in 6-12 months and produces a sweet aroma when burnt.
Apple
Apple, like oak, has a BTU of 27 million; it is a hot-burning wood. However, it is harder to find than oak. If you buy apple wood, it makes excellent aromatic fires and produces intense heat.
Hornbeam
Hornbeam’s BTU is similar to oak and apple wood: 27 million BTU. It is easy to find in some parts of the United States. It gives off high-intensity, long-lasting fires that can rage for 6-8 hours.
Walnut
Walnut is one of the runts of the litter on this list. Its BTU is 22 million, just like the cherry. However, it does not last as long since it is low-density. It typically burns for a shorter time.
Hawthorn
As far as longevity goes, hawthorn sits in the middle of oak and hickory with a BTU of 25 million. It burns hot and long. However, due to its large spikes, it is usually not sold for firewood. Hence, you may not find them easily unless you grow them in your yard.
Osage Orange
If there was a list of “the hardest to find firewood,” osage orange may top it. They come first in density and heat intensity with a BTU of 34 million. You cannot use the osage orange indoors. The reason is that it produces too many sparks. It would help if you mixed it with cooler burning woods like cherry or ash.
Burnt Out Firewood
Conclusion
To know “how long does firewood burn?” you must learn the factors that affect the firewood burn time. The kind of wood, its moisture content, and its health status play a significant role.
Generally, denser wood will burn longer. Fortunately, in this article, you have discovered which firewood burns longest. With this knowledge, you can sleep better because you know that your firewood can keep you warm all night.