Firewood
We produce and offer firewood according to customer specifications. Our available species include birch, alder, ash, hornbeam and oak, all sourced locally in Lithuania.
Packaging options for firewood include net bags and crates. Our expertise covers various packaging sizes, including 22, 30, 40, and 60-liter bags, as well as 0.6m3, 1.2m3, 1.8m3 and 2m3 crates. Firewood can be prepared to the customer's desired length, ranging from 20 to 45 cm. We offer fresh-cut (natural), Air-dried (seasoned) or Kiln-dried (under 25% moisture) firewood.
Firewood Production Process
Firewood calorific value groups
Different firewood species have unique characteristics based on their density. The first group burns at the highest temperature and is ideal for larger boilers used in house heating. Birch is best suited for barbeque fireplaces or saunas. The third group burns at a relatively lower temperature, making it safer for smaller furnaces and reducing the risk of chimney wall cracking.
The value of timber species, in Relation to Volume and Mass table:
Timber weight and volume ratio
Firewood Moisture Content
Firewood is available in three moisture levels
Kiln-Dried
<25%
Air-Dried
25-35%
Fresh
35-55%
For kiln drying
We use drying chambers.The standard drying cycle in the kiln lasts 100 to 150 hours, with a maintained temperature of 60°- 90°C. Following drying, the firewood is left outside for at least a few days to ventilate excess vapor.
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For natural air-drying
We utilize the yard adjacent to the warehouse. Boxes are spaced with a 30 cm clearance to ensure 360° air ventilation and rapid moisture release. During storage, each box is covered from the top to protect against direct rainfall.
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Fresh Firewood
For the summer season, we recommend stocking up with fresh firewood. This approach not only saves money, as firewood timber prices are lowest in the spring, but also allows the firewood to naturally dry over 3 to 4 months, reducing or eliminating the need for chamber drying and saving on drying costs.
Formula of Average Firewood Humidity is used to determine the moisture limit in kiln-dried firewood. Moisture levels are measured at the outside end, inside end, and inside center of the log, with the average moisture calculated as the sum divided by three. Standard logs typically have 15-20% outside moisture and approximately 30% moisture in the very center.
Firewood Packaging
The firewood is conveniently packed into wooden boxes for easy access. When packed into bags, they are then stacked into these boxes. Utilizing boxes is the optimal method for handling and transporting firewood. The primary constraints are the cargo weight, limited to 24 tons, and the space within the trailer. Volume constraints are seldom an issue (excluding sea containers), and the quantity of boxes depends on their size, the type of timber, and the moisture content of the firewood.
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Various loading schemes for firewood into trucks are detailed in the table below:
Firewood boxes in truck
The volume of firewood in boxes is measured in Raumeter or Stere. 1 RM or Stere is equal to 1 m3. The typical box dimensions (measured Inside, Length x Width x Height, m):
Box contains
1 RM = 1.17 x 0.92 x 0.93 m
Box contains
1.8 RM = 1.12 x 0.8 x 2.0 m
Box contains
2 RM = 1.13 x 0.93 x 1.9 m
*+/- 2 cm tolerance due to handcraft and other factors is accepted. The dimensions of box shall be equal or very close to announced volume (i.e. 1.13x0.93x1.9=1.9967m³ is called a 2 RM box).
For the outer dimension of box (to calculate the floor space required), add 5-7 cm on each inner dimension.
To convert one Raumeter volume to solid wood volume, following coefficients are used:
On the average 1RM = 0.62-0.64 m³ of solid wood.
Coniferous trees 1RM = 0.53 – 0.68 m³; Leafy (hardwood) trees 1RM = 0.49 – 0.67 m³.
The regular log is 8 to 15 cm in diameter. The length can be 25 cm, 30 cm and 45 cm and depends onto which size (1RM, 2RM or 1,8RM) box they are stacked. The box has 1-2 rows of firewood pile on top.
The different log length determines the volume multiplier. The shorter the log, the less “empty space” there’s in the box. Hence, the 30 cm logs occupy space in box more complete than i.e. 45 cm logs. To understand the volume in Raumeter (Steremeter), as compared to solid wood volume, the table below to be used. A reference point is a 1 x 1 x 1 meter box, filled with 100 cm long logs. This box would have a multiplier of 1.
Length of logs and volume in a box
Example: if you have 2m³ of firewood, cut into 100 cm logs, it would occupy exactly 2 RM. If you have a 2m³ box with 30 cm logs inside, it equals to 3.04 m³ of solid wood. If 2m³ of solid firewood are cut into 25 cm logs, the space occupied then equals 2 m³ X 1.67 = 3.34 RM. Simply – the shorter the logs are, the more “solid” timber the same size box contains. Most popular length is 30 cm.
For bag production, Biodela specializes in 40-liter bags. The standard size for these bags is 50 x 72 cm, weighing 14.5 - 15.5 kg for kiln-dried firewood. Other popular sizes include 22, 30 or 60 liters.
Additionally, we offer kindling sticks as a popular product. These fire starters are 10-12 cm long, with a diameter of approximately 2 cm and a humidity of 10-15%. The sticks are packed into 9.5-liter bags (weighing 3 - 3.5 kg) or 30-liter bags (weighing 5 - 5.5 kg).
Firewood Quality management
The quality of the firewood box and its residual moisture (if dried) are paramount considerations. An ideal firewood box features sturdy side boards and securely attached straps to withstand the rigors of transfer and loading.
The side boards should be approximately 5 cm wide and have a correct rectangular shape. Three sides of the box are closed, with the frontal part left open for convenient access to the logs. Additionally, the box should have at least two straps securing it between the top and bottom.
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​Logs must be split, at least into halves, and often into quarters or sixths diagonally. The box should contain only firewood logs, with no remaining timber or waste wood. It's essential that the logs are free from mold.
Measuring the moisture content of firewood
The moisture content of firewood is measured by taking an average across the log, as there is no way to dry the entire log uniformly. This average moisture level serves as the standard measurement
Here is the method for measuring the humidity of firewood
Take an average-sized firewood log from the center of the box.
Split the log and leave it indoors for 30 minutes to allow for evaporation.
Take three measurements:
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Center of the outer side of the log,
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End of the log,
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Center of the split log inner side.
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Calculate the average of these three measurements to determine the humidity content.
Dry firewood is considered to have no more than 25% humidity content unless otherwise agreed upon. There are no limits for the humidity content of fresh firewood.
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Storing firewood requires careful consideration to avoid potential issues
The key steps to prevent problems with firewood are:
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Protect from moisture absorption.
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Shield from direct rain.
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Prevent mold formation by ensuring adequate ventilation.
The optimal location for storing firewood is outdoors, in an open area with good airflow and protection from the elements, such as under a cover or roof. This setup promotes proper ventilation and reduces the risk of mold growth. Alternatively, firewood can be stored in a warehouse provided that sufficient 360° ventilation can be ensured. When storing fresh firewood outside, it will dry faster if exposed to direct sunlight. In such cases, we recommend covering the boxes with transparent plastic tops to protect them from rain.