Freshly chopped firewood contains up to 50 percent water content, meaning it cannot burn in your fireplace or fire pit. You first need to season the firewood to allow the excess moisture to escape. Seasoning reduces the moisture content of wood to less than 20 percent. Firewood with moisture content higher than that may eventually burn, but it will be hard to light. Even if you get it to light, it will be a mediocre fire at beat
In addition, your furnace or wood burning stove will perform sluggishly as it struggles to burn the firewood. Most of the energy and heat produced are wasted in drying the excess moisture in the wood. Unseasoned firewood also blackens the glass windows of your wood burning stove and produce lots of blue-gray smoke, which fouls your house and annoys your neighbors.
- 1 What Exactly is Seasoning?
- 2 Steps to Season Firewood Properly
- 3 How to tell if Your Firewood is Fully Seasoned
- 4 Methods of Seasoning Firewood: Kiln Drying Vs. Air Drying
- 5 Types of Wood: Hardwood vs. Softwood
- 6 Seasoning Firewood: Types of Moisture in Wood
- 7 The Benefits of Seasoning Firewood
- 8 How Wood Dries
The only way you can avoid these problems is using seasoned or dried firewood. Firewood is easy to dry, provided you give it the correct drying conditions. With a little basic info about seasoning firewood, you can avoid the simple mistakes most people commonly make. This will give you wood that’s easy to light, will burn cleaner, give more heat per cord and will make some awesome campfires. In this article, we will all the essential details you need to know about seasoning firewood.
What Exactly is Seasoning?
Seasoning is the process of drying wood until its moisture content is between 20 to 25 percent, with anything above that qualifying it as “unseasoned”. Seasoning can take a long period of time depending on the type of firewood you and the climatic condition.
There are two types of wet firewood: freshly chopped wood and seasoned wood that got wet. Freshly chopped wood still contains high levels of moisture in its living cells and has a tree sap. Seasoned wood is the wood that has been dried enough for the moisture and sap to escape. If seasoned wood is left out in the rain, it will soak up water and will require drying before it is ready for burning. Freshly chopped firewood takes longer to dry that wet seasoned wood.
In this video I found below, you will find some helpful tips to deal with seasoned firewood that has gotten wet.
Climatic conditions also affect the period it takes to season firewood. Wood will certainly dry faster during hot dry summers than in foggy, damp, cool climate. Seasoning firewood can take months to over a year or more depending on the dry conditions. We will teach you how to shorten this time, but before that let’s discuss the various types of wood and wood-water relationships.
Steps to Season Firewood Properly
Step 1: Plan Ahead
Wood takes time to fully season. Thus, consider cutting your wood early in the spring if you are planning to use it in the fall. Similarly, determine how much firewood you will need through the season and buy just enough. If you burn 1 to 2 fires a week, three cords of firewood should be enough. Note that a cord of firewood refers to a stack 8 feet long, 4 inches high and 16 inches deep.
Step 2: Prepare Your Log Store
Once you decide the amount of firewood you need to season, you need to prepare your log store. Log stores come in a wide range of options, sizes and styles. For a more personal touch, you can consider building your own.
Whatever design you choose, your log store must have a good roof to protect the firewood from adverse climatic conditions. The roof should be slanted to allow water to run off. More importantly, the have the roof overhang the wood pile on all sides so that it fully protects and prevents water from dripping on the firewood.
It should also be well ventilated on at two sides to allow for a good air circulation. Proper air circulation is needed to make the seasoning process as efficient as possible. In addition, your log store should be off the ground to prevent logs from getting wet as well as to maintain a good supply of air flowing via the base. Avoid pushing your log store against the wall as this prevents air from moving around the logs.
When it comes to positioning your log store, try placing it in a sunny, breeze location to enhance the drying process. If you think that your log store will be exposed to heavy rain, consider covering the wood pile with a tarp. However, you should remove the cover at the next convenient occasion to keep the store properly ventilated.
Step 3: Cut the Wood to Length
The wood you have bought or cut yourself should be the right length of your furnace, fireplace or cooking stove. In most cases, this is about 3 inches shorter than the length or width of the firebox, depending on how you load the firewood. Generally, it is better to have firewood a little shorter than ideal as shorter pieces are easier to handle and quicker to dry. You can do this many ways but a chainsaw might be the easiest.
Normally, firewood is 16 inches in length, partly because this length is one third the 48 inch width of a full cord of wood. Secondly, pieces of firewood that are more than 16 inches tend to be difficult to handle. Note that quality firewood should have a consistent length and should not vary by more than an inch or so.
Step 4: Split the Firewood to the Right Size
After cutting the firewood, the next step is to split it to the right size with a splitting axe or log splitter for your burner. For most efficient wood stove, this is usually no more than 6 inches measured at the largest cross sectional dimension. However, some furnaces can use firewood that is a little larger in cross section.
Even for furnaces, un-split pieces make lousy firewood. A range of log sizes is ideal so that as you kindle a fire or reload on a coal bed, you can have some smallish pieces to help you achieve the desired instant ignition.
If you need firewood for your wood stove, a selection of sizes ranging from 3 to 6 inches in diameter will probably serve you well. Similarly, for furnaces consider cutting the wood to 8 inches diameter to get the best burn. Note that firewood begins to season efficiently once it is cut and split to the correct size. When it is in log form, the moisture is held in by the bark.
Step 5: Pile the Wood in a Single Row Exposed to the Sun and Wind
The best place to dry freshly chopped wood is outside. If you throw the wood straight into the wood shed, it will take too long to dry as it is not get sufficient sun and air movement. For optimal results, consider stacking firewood in a single row up off the ground so that the sun and breeze can remove the excess moisture on the cut ends.
Remember that most freshly cut wood contain 30 to 50 percent moisture content and you will need to get it down to about 15 to 20 percent for it to burn efficiently. Wood that is too wet creates a lot of smoke and if it burns at all it produces little or no heat.
If you do not have enough space to dry your firewood in a single row, you can stack a few rows together. However, consider leaving some space between the rows for the sun and wind to penetrate the stacks. This will significantly reduce the period of time it takes for the pile to fully dry.
Step 6: Allow the Wood to Dry for At Least 6 Months or Even Longer
If you have stacked your wood in well-spaced rows, it should have lost most of the moisture in about six months. Thus, if you have your firewood stacked in early spring, it should be ready for use in winter. However, it may take longer, especially if you live in damp maritime climate or use very dense wood, such as Oak, which takes over a year to dry. If you use very hardwood, it is recommendable to start seasoning it in the fall for use in the following fall. That way you’ll be sure it has seasoned properly.
If you are opting to season your firewood for a long period of time you must be ready for everything. Ensure that your wood can withstand all conditions and STAY DRY. If you dont have something built, I highly recommend using a tarp of some kind.
How to tell if Your Firewood is Fully Seasoned
One of the most common problems wood burners is poor performance due to the use of wood that is not fully seasoned for optimal burning. This naturally leads to the question: How can you tell your firewood is properly seasoned?
Feel the Weight
Wood that is fully seasoned weigh less than freshly chopped wood.
Drier wood has a looser bark, which tend to fall off more easily. However, this does not mean that any wood that still has a firm bark in place is not fully seasoned. But in a cord of readily dried wood you can find a few pieces of wood that have their bark fallen or peeled off.
Wood that is fully seasoned makes a clear, high pitched “click” when two pieces beat together. Freshly chopped wood make a dull “thud” sound when struck.
The cambium refers to the thin layer between the sapwood and the bark. If you think that some freshly chopped wood has not seasoned, peel the back section of the bark and check for greenness in this layer. If it is green, the wood has not yet seasoned.
As firewood dries, the color of the sapwood on the split ends fades. A cord of fully dried wood looks dull and subdued rather than bright. It should also have splits and cracks visible on the ends.
Freshly chopped wood has a pleasant smell with a sap-tinted aroma. Wood that has fully seasoned still smells like wood, but the scent is not as strong as that of fresh green wood.
Use a Moisture Meter
A moisture meter is a handheld device that measures the moisture content in a log by calculating its resistance to electric current. It is one of the quickest methods of determining whether your firewood has seasoned. To get more accurate results of how dry your firewood, be sure to test different logs from different places in the pile.
Knowing how to season firewood properly allows you to have a reliable heat source during the cold months of winter. Finally, when it comes to burning your seasoned firewood, it is a good idea to bring them in the morning before the evening you plan to burn them. This allows any condensation to dry if they come in from the cold outdoors.
Methods of Seasoning Firewood: Kiln Drying Vs. Air Drying
There are two major ways of drying firewood: Kiln and air drying.
Firewood Drying Kilns
Kiln dried firewood is dried in a heated chamber removing water at a very high temperature. Firewood drying kilns are specifically designed to dry firewood in a very short period of time. They resemble lumber drying kilns and have a minimum temperature of 160 degrees. Some kilns also dry firewood at very high temperatures of up to 200 degrees. They can season green firewood in just 48 to 72 hours to a moisture content of below 20 percent.
Kilns are usually powered by natural gas, electricity or even solar energy. When firewood is backed in this way all the moisture quickly evaporates off. This not only reduces the amount of time it takes to dry the wood, but also eliminates the problem of storage space. Kiln drying also ensures that the firewood is seasoned evenly.
Advantages of Kiln Dried Firewood
· Firewood contains a very low moisture content
· The wood is bug free
· Kiln dried firewood burns clean and complete with little ash and no Creosote
· Wood produces the highest BTU’s of any firewood
· Firewood is dried quickly, in just 48 to 72 hours
· Seasoning can be done throughout the year since kilns are not affected by changes in climatic conditions
Disadvantages of Firewood Drying Kilns
· They are expensive to acquire and maintain. They are mainly used by large suppliers of firewood.
· Kilns can dry firewood to moisture content below 20 percent, depending on its heating temperature. Excess drying causes volatile esters to leave the wood, leading to a low BTU.
Air Dried Firewood
Air drying entails is one of the most commonly used methods of drying firewood. It entails seasoning firewood outdoors using the wind and sun to get rid of the excess moisture. Air dried firewood varies in moisture content and drying time due to various environmental factors. Air drying is less costly compared to kiln drying. It is a DIY process that produces optimal results if done correctly. In the next section, we will discuss the critical steps to follow when seasoning firewood using the air drying technique.
Benefits of Air Dried Firewood
· It is the most affordable firewood seasoning method
· It allows to season large quantities of firewood one at a time
· The firewood does not have to be moved from where it is process
· When compared to kiln drying, air drying is less labor intensive
· Buyers can buy seasoned firewood from the drying area at a very attractive price
Disadvantages of Air Drying
· Firewood takes a long time to dry, depending on type of wood being seasoned. Soft woods may take 4 to 12 months while hardwoods may take about a year.
· Sometimes, air drying results in firewood with parts that are fully seasoned and parts that still contain some moisture. This causes issues when burning.
How to Season Firewood Properly using the Air Drying Technique: The Critical Steps to Follow
Now that you clearly understand all the basics of firewood seasoning, let’s discuss the critical steps you need to follow to air dry your freshly chopped firewood properly.
Types of Wood: Hardwood vs. Softwood
There are two types of wood: softwoods and hardwoods.
Softwoods are from coniferous tress. They have a simple structure. They are typically much lighter and easier to process than hardwoods. Softwoods have a density ranging from 350 to 700 kilograms per meter cubed. Softwoods are good for starting a fire but will release a low amount of heat per volume. They contain a high amount of sap and thus they are not recommended as indoor firewood.
Softwoods may build up dangerous amount creosote in your chimney. However, if you want to burn softwoods as firewood, make sure you are monitoring everything… Here are the best options:
· Yellow pine
Hard woods, on the other hand are from broad leaved trees. They have a more complex and dense structure, which makes them “harder”. Hardwoods have a density ranging from 450 to 1250 kilograms per meter cubed. Due to their high density and complex structure, hardwoods have a lower permeability, making them difficult to dry. Hardwoods, such as beech can take up to two years or longer to fully dry.
Hardwoods are highly recommended for use as firewood. This is because they tend to have a higher BTU (heat per volume) compared to softwoods.
Although they may be difficult to start, they will burn longer and dissipate a good amount of heat. Some hardwoods are better than others. Examples of quality burning hardwoods (especially if they are properly seasoned) include:
There are other hardwoods that may burn well, but are usually difficult to acquire in volume for firewood. Even though most hardwoods burn well, there are a few that do not. Sycamore, Popular and Elm are among the few hardwoods that are not ideal for use as firewood due to their poor characteristics.
Here is a complete list of all of the hardwood and softwood trees. Please note that these woods are all not recommended for burning.
Seasoning Firewood: Types of Moisture in Wood
Green wood contains a large amount of water that usually constitutes over 50 percent of the wood’s weight. Freshly chopped wood contains three forms of water:
This is the bulk water contained in the cell Lumina. The water is held by capillary forces. Free water does not contain any chemicals that alter the drying characteristics of wood.
Hygroscopic or bound water
It is the water held in the wood through hydrogen bonds.
This is the water that trees readily release during transpiration.
The three types of water determine the total moisture content of the wood. Wood with high moisture content may take long to dry.
The Benefits of Seasoning Firewood
Finding the right type of food is vital for getting the most out of your furnace or wood burning stove. Firewood should be seasoned properly to ensure that the fire burns hot without a lot of smoke. Unseasoned firewood contains a higher moisture content that makes it difficult to light and burn. Here are some of the top benefits you can enjoy by seasoning firewood.
Higher Heat Efficiency
It stands to reason that firewood with high moisture content is hampered from dissipating optimal heat in wood burning stoves. Although the concentrated effects of wood burning stoves allow for ideal heat and controlled input via the ventilation systems, without seasoning the firewood properly, the stove cannot produce the highest heat efficiency to reach its maximum operating temperature.
Seasoned wood burns at a much higher temperature. Higher the heat content means that you will use less quantity of firewood to warm your entire home. A higher heating efficiency also helps to enhance the use and life of your stove.
Smoke emanating from freshly chopped wood is not only unpleasant for those trying to enjoy a roaring fire, but it also reduce the life of your stove. Buildups from the smoke coat the stove and reduce its efficiency. Seasoned wood has lower moisture content, so there’s virtually no additional smoke produced due to excess water content.
Seasoned Wood Burns Longer
Burn time is a crucial factor for wood burning stoves. The longer the burn time, the more heat is produced. A longer burn time also means you will have less work to keep the fire going. Seasoned firewood has an exceptionally long burn time compared to green or freshly chopped wood.
Avoid Bringing Mold to Your Home
Moisture encourages mold to grow. Thus, when you dry your freshly chopped or wet seasoned firewood, you reduce the odds of mold growing on the firewood. You consequently lower the likelihood of bringing mold into your home.
How Wood Dries
Wood contains three types of water: free water, hygroscopic and vapor. When you chop a tree down, free water is the first water to be released. Free water is usually contained in the bark and cell lumina. The wood is not fully dry even after the water in the bark goes. Full season occurs when all the water in the cell lumina leave and the wood begins to shrink and crack.
Note that different species of tree woods have different cell structure and chemical composition. This explains why different types of firewood have different seasoning period. Thus, when choosing your firewood, it is imperative to know its properties so you can best determine the amount of time needed for the wood to season properly. Hardwoods take the longest amount of time to season, usually between one and two years, while softwood trees, such as pine take between 6 to 18 months to dry.