Is Fir Good Firewood?

Fir is a softwood that can be seen all around the globe. Fir (Abies) are evergreen coniferous trees, which means they remain green all year round. The fir tree can grow massive, with trunk diameters from 1 to 13 feet in circumference. But, do Fir trees make good firewood?

In short, Fir is not great firewood because it burns quickly, throws sparks, and only produces a medium amount of heat: from 12 up to 21 million BTU’s per cord depending on the variety. Furthermore, the wood is rich in resin, making it messy while it also has a lot of knots, making it challenging to split.

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Can You Use Fir Trees For Firewood?

Fir varieties can certainly be used as firewood but it is not recommended to burn fir in an open fireplace or use it as the main heating source.

There are a number of reasons to back up this argument:

  • First of all, fir has a high resin content. That creates a number of issues like making it uncomfortable to handle.
  • Besides that, high resin content makes it crack, pop and throw sparks.
  • Due to resin it also does not burn as clean, creating more creosote than hardwoods.
  • It is a softwood with low BTU output.

But let’s have a deeper look at all the factors.

What Are The Different Varieties Of Fir?

Fir trees have many different varieties, some of the most popular are listed below:

Douglas Fir is a softwood that provides modest heat, 21 million BTUs per cord, and is easy to start a fire with. It is among the best conifers for firewood, even outperforming certain hardwoods in overall heating value.

Balsam Fir is exceedingly soft and has a very low heat output of 15.8 million BTUs per cord. yet its sap content allows it to be used for kindling.

Another variety is Concolor or White Fir. Concolor is similar to Balsam fir, with a low BTU value up to 15.8.

Most of the Fir trees have very low BTU values with a small exception of Douglas fir varieties, which are slightly better.

What Are The Physical Characteristics Of Fir?

Before we go into Fir’s fire and heat qualities, it’s vital to discuss certain physical features that play a role in when it comes to firewood aspects of it.

Is Fir Easy To Split?

Fir is claimed to be among the simplest splitting firewoods due to its straight grain pattern, but in reality, they tend to be difficult to split. That’s because most varieties are full of knots, and going through them is many times a laborious process.

It does have to be noted though that it varies from tree to tree and the specific conditions in which the tree has matured.

The Smell

The scent of fir wood is pleasant. It doesn’t have the same strong scent as Cedar, but it smells better than most firewood. The resing gives it a unique menthol-like scent, which in some can be with a dull or sharp undertone.

Resin Content

Fir has extremely high resing content that can be easily noticed on injured trees. The high sap content makes it difficult to handle the firewood without getting dirty. The resin is sticky in nature and sticks to the clothes almost permanently while it is also difficult to wash it off the skin.

The Moisture Levels

Green or freshly cut firs have relatively low moisture content compared to other evergreen firewood like cedar.

The easiest way to tell the difference between the level of moisture content would be to compare the weights of wood seasoned and green. (check this table here). First have an only a slight difference between the numbers (a few hundred), whereas cedar weights differentiate 800-1000 lbs.

Heat Output And Efficiency Of Fir

Much information is available regarding the quantity of heat produced by fir trees. Some estimated as little as 17.4 BTUs per cord, while others estimated as much as 26.5 BTUs each cord. The enormous disparity in these values might be attributable to scientific factors determining how much genuine solid wood is in a cord. 

However, numerous studies show that Fir’s heat production and efficiency are not as great as other firewoods since it has a low BTU and cannot provide heat in your house overnight.

Fire Characteristics Of Fir

The most essential aspects in determining the fire qualities of firewood are Creosote build-up, the amount of smoke created, and whether or not any coal is left after burning.

Creosote Buildup

A common concern among people is that fir wood causes creosote buildup in your chimney. The argument is valid, but there are a few things to minimize the creosote build-up.

Using properly seasoned fir wood and cleaning your chimneys more often would be the two things to keep in mind if you plan on using fir on a continuous basis.

Amount Of Smoke

Fir is a softwood while having high sap content. Both of these factors contribute to the fact that fir produces a medium amount of smoke when burned.

Coal Production And Why Is It Important

In this aspect, fir is not the strongest either, as it is softwood. In some instances, the knots of the wood can last pretty long in the fireplace, but it is still not sufficient enough.

Due to low coal production, using fir as firewood requires a lot of maintenance and keeping an eye on the fireplace constantly, ensuring it does not burn out.

Should Fir Be Burnt In A Fireplace?

As I said earlier, fir can be used as firewood, though it is not the best option it can keep you warm if you are in a pinch. In some areas, fir and other conifers are the only accessible source of firewood.

One thing to avoid is burning fir in an indoor open fireplace as it tends to crack and throw sparks.

As long as you use a log burner with a door and maintenance your chimney or flu properly there is nothing to worry about when it comes to burning fir.

How Long To Season Fir Firewood?

A year is more than enough to season your fir tree, but if you split, break, and pile it in the springtime, it will be ready for winter. When you take down dead standing trees, you may typically burn the firewood for six months without any problems. 

For any firewood, including fir, you should aim for moisture content below 20% before burning.

How fast that can be achieved depends on an array of factors, including but not limited to the weather and storing conditions, if the wood is split green or not.

In ideal conditions, if the average temperature is above 50 degrees Fahrenheit, fir is split green and stacked right away in an area with adequate airflow it can dry enough in 6 months to be used in a fireplace.

In most cases to reach the desired 20% moisture content, the average time it takes to season fir is 10-12 months.

Is Fir Firewood Expensive?

Fir is definitely not the most expensive firewood you can buy. In fact, it is difficult to find since many sellers only offer premium quality hardwoods like locust, maple, or oak.

When buying fir seasoned and split fir wood, you can expect to pay slightly less than it would cost to buy premium hardwood varieties. For one cord of wood, you can expect to bay in the ballpark of 350USD.

Pros And Cons Of Using Fir As Firewood

PROS

  • Good for kindling
  • Easy to light
  • Seasons fast

CONS

  • High resign content
  • Medium smoke
  • relatevely low heat output

How Does Fir Compare To Other Firewood?

Most fir varieties do not have a high heat output as hardwoods, but Douglas fir (20.7BTUs) is a good candidate competing with medium quality firewood such as cherry and hackberry which have a heat output of 21 and 22.5 respectively.

Although Douglas fir heat output can be similar to medium quality firewood, other fir varieties are more on the lower end of the spectrum in terms of heat output. The lowest being Corgbark fir with 12.8 million BTUs per cord.

Besides that, firs also produce more smoke, creosote, and sparks, making them less desirable than cherry and hackberry firewood which have lower sap content.

Frequently Asked Questions

Is white fir good for firewood?

White fir has a heat output of 15.8 Million BTUs per cord. Combining it with other peculiar properties of fir varieties, it is less than a mediocre wood to use as a heat source.

Is Balsam fir good heat source?

Balsam fir has the same heat output as white fir, 15.8 million BTUs per cord of wood therefore it is not preferred to burn it exclusively for heat.

Conclusion

Fir can be a great source of heat, depending on the variety. For example, most Douglas fir varieties have a BTU rating similar to medium-quality firewood like hackberry. Most firs on the other hand have a low heating value, making a good material for kindling or to burn in campfires.