The question of how much firewood is in 5 cubic meters often confuses not only those who are purchasing fuel for a fireplace or sauna for the first time, but also experienced homeowners. It would seem that the mathematics is simple: five cubic meters is five cubic meters. However, in real solid fuel trading, the concept of “cube” can have completely different physical meanings. Folding meter and dense meter are two different units of measurement, and confusion between them can cost you a significant chunk of your budget.
When purchasing chopped or split-sawn firewood, voids inevitably form between the logs, which occupy up to 30% of the volume. That is why, when ordering a car with a 5 cubic meter body, you can get significantly less wood in weight and calorific value than you expected. Understanding these nuances will allow you not to overpay and accurately calculate the required amount of fuel for the season.
In this article, we will look at how to correctly convert volumes, what weight different types of wood have, and what to pay attention to when accepting goods. You will learn to distinguish an honest seller from one who is trying to deceive, using the peculiarities of laying logs. Exact calculation - the key to a warm winter and saving money.
Difference between folded and dense cube
The first thing to understand when purchasing solid fuel is the fundamental difference between dense and folded volume. Dense cube (or cubic meter of wood) is the volume that wood would occupy if there were no bark, voids and air. This is a theoretical value used for calculations in forestry and lumber production.
In real life, when firewood is split and loaded into a machine, it forms folding meter. A significant part of this volume is occupied by air pockets between the logs. The conversion factor depends on the length of the log, the type of wood and the accuracy of laying. For long logs this coefficient can be 0.8, and for short, chaotically thrown logs it can drop to 0.6-0.7.
Volume conversion formula
To convert folded meters into dense ones, the full wood coefficient is used. For example, for birch split firewood 0.33 m long, the coefficient is approximately 0.7. Multiplying 5 folded cubes by 0.7 gives 3.5 dense cubes of pure wood.
When you ask the seller how much firewood is in 5 cubic meters, clarify exactly what volume we are talking about. Often, unscrupulous suppliers name the price per folded meter, passing it off as dense, or they load the car “heaped”, which after shaking turns into a hole. The actual volume of wood in 5 stacked cubes of split firewood is approximately 3.5–3.8 cubic meters of dense wood.
When accepting firewood, request unloading into a flat woodpile or use a measuring box (crate) to check the volume, since it is extremely difficult to visually estimate the quantity in bulk in the body.
How much does 5 cubes of different types of firewood weigh?
The weight of the fuel directly depends on the type of wood and, critically, on humidity. Freshly cut wood can contain up to 60% water, while dry firewood has a moisture content of about 15-20%. The difference in weight between wet and dry birch can reach 40%, which significantly affects logistics and delivery costs.
Let's look at the main rocks used for heating. Birch is considered the standard for calorific value and is in greatest demand. Aspen burns hot and helps clear the chimney of soot, but burns faster. Oak and beech belong to hard rocks, they burn for a long time and give a lot of heat, but they are more difficult to chop and ignite.
Below is a table showing the approximate weight of 5 stacked cubic meters of firewood depending on the type and humidity. The data is averaged, since the density of wood may vary depending on the region of growth.
| Wood species | Condition | Weight of 1 folded m³ (kg) | Weight 5 folded m³ (kg) |
|---|---|---|---|
| Birch | Dry (20%) | ~450 | ~2250 |
| Birch | Fresh (50%) | ~600 | ~3000 |
| Aspen | Dry (20%) | ~400 | ~2000 |
| Oak | Dry (20%) | ~550 | ~2750 |
| Pine | Dry (20%) | ~350 | ~1750 |
As can be seen from the table, 5 cubes of dry birch will weigh more than two tons. This is an important parameter for planning unloading: manually shoveling such a volume is difficult and time-consuming. Mechanized unloading or ordering a machine with a manipulator often justifies the additional expense.
Body geometry and actual load
When it comes to 5 cubic meters of firewood, most often we mean the standard GAZ-53 truck (GAZ-53A) or its modern analogues (GAZ-3307, GAZ-3309). The bodies of these cars have different sizes, and loading geometry plays a decisive role. The standard GAZ-53 body measures approximately 3.1 m in length, 2.3 m in width and 0.6-0.7 m in side height.
The mathematical volume of such a side without superstructures is about 4.5–5 cubic meters. However, if you simply throw firewood into the body, it will take up the entire volume, but after shaking during transportation, the level will drop significantly. An honest loading “level with the sides” will give about 4-4.5 folding cubes. To get the stated 5 cubes, the firewood must be stacked neatly or have extensions (extended sides).
⚠️ Attention: If the seller promises 5 cubic meters of firewood in the back of a GAZ-53 without extended sides and without very careful installation, this is physically impossible. The actual volume of such a body is limited by geometry and is no more than 4.5-4.7 m³ when loaded “with a small slide”.
There are also ZIL-130 cars, the body volume of which is about 6 cubic meters. When ordering 5 cubes from ZIL, you will receive a full body, but not to the top. Always check the model of the car that will come to you. Body volume - this is not the same as cargo volume.
☑️ Check when accepting firewood
Effect of humidity on volume and combustion
Humidity is the hidden enemy of efficient heating. When you buy 5 cubic meters of raw firewood, you are actually paying for water. When raw wood is burned, a significant portion of the energy is spent on evaporating moisture rather than heating the room. In addition, raw firewood takes up more volume with the same energy value.
Dry firewood (humidity 15-20%) has less weight and takes up a little less space due to drying, but their calorific value is 1.5-2 times higher than that of freshly cut firewood. Burning wet wood leads to the formation of condensation in the chimney, which mixes with soot and forms an aggressive acid that destroys brickwork and metal.
Humidity can be determined visually and by ear. When a dry log hits another, it makes a ringing, booming sound. Damp wood sounds dull. There is no protruding moisture on the cut of dry firewood, and the bark is easily separated. Ideal option wood is considered to be wood that has lain under a canopy for at least one summer season.
Calculation of the amount of firewood for the heating season
How much firewood is needed to heat a house? Is 5 cubes a lot or a little? The calculation depends on the area of the house, the quality of insulation, the type of stove and the region of residence. For a well-insulated house with an area of 100 square meters in central Russia, a season may require from 10 to 15 cubic meters of birch firewood.
Thus, 5 cubic meters is approximately half the winter supply for an average home or a full supply for a small bathhouse or country house, which is visited only on weekends. If you only use wood to light the fireplace in the evenings, then 2-3 cubic meters may be enough for the entire season.
When planning purchases, keep in mind that buying firewood in bulk (in 5-10 cubic meter units) is always more profitable than in small quantities. However, large volumes of fuel must be stored in a dry, ventilated place. Woodcutter should protect the logs from precipitation, but not interfere with air circulation.
The optimal purchasing strategy is to buy 5-10 cubic meters of dry firewood in the fall, when prices are lower, and store them in a ventilated woodshed until the end of the season.
Common mistakes when purchasing and storing
One of the most common mistakes is buying firewood in the summer in the hope that it will dry out by winter. In summer, wood dries slowly due to high air humidity, and by autumn it can begin to rot if piled without access to air. It is better to buy already dry firewood or split it yourself in early spring.
Another mistake is storing firewood in plastic bags or thick film. This creates a greenhouse effect, and the tree begins to rot. Covering material should be breathable or placed only on top of the woodpile, leaving the sides open.
⚠️ Attention: Never store firewood close to the walls of the house or inside residential premises in large quantities. This violates fire safety and can lead to the appearance of wood-boring insects in building structures.
Also, don't underestimate the importance of sizing your logs. Modern solid fuel boilers with automatic feeding or pyrolysis furnaces require fuel of a certain fraction (usually 25-33 cm). When ordering 5 cubes, check if they can cut wood to fit your firebox size.
Questions and answers (FAQ)
How many logs are in approximately 5 cubic meters of firewood?
The exact amount depends on the size of the logs. One folded cubic meter of chopped firewood (birch, length 33 cm) contains approximately 350-400 medium-sized logs. Therefore, in 5 cubes there will be about 1800-2000 pieces. If the firewood is not split (round wood), the quantity will be less, but the weight and volume will remain the same.
Is it possible to use a GAZelle to transport 5 cubes?
A standard GAZelle (3-4 meters) physically cannot accommodate 5 cubic meters of firewood, even with high extensions. The volume of a GAZelle body is usually 8-10 m³, but firewood cannot be loaded above the roof or the axle must be overloaded. For 5 cubic meters of firewood you will need a GAZ-53 or ZIL class car, or two trips in a GAZelle with high sides.
How to correctly convert firewood from linear meters to cubes?
Recalculation is possible only by knowing the cross-section of the log. Formula: Length (m) × Width (m) × Thickness (m) × Number of pieces. However, in practice, firewood is sold in stacked cubic meters, so it is easier to measure the volume of a stacked woodpile: Length × Height × Stacked Width.
Why is firewood in bags more expensive than in bulk?
Firewood in mesh bags (usually 40-50 liters) is packed manually, which increases labor costs. In addition, dry, calibrated premium firewood is often sold in bags. The price per cubic meter in terms of bags can be 2-3 times higher than when buying by machine, but this is a price for the convenience of storage and the absence of garbage.