In Germany it is forbidden by law to burn damp wood. The first regulation for the implementation of the Immission Control Act stipulates that the moisture level of firewood must not be higher than 25 percent. Since the moisture content of freshly cut wood is around 60 percent, the fuel must first be dried. How – you will find out in the following article.
How should you dry firewood properly?
To dry firewood, it should be stored outdoors with good ventilation and sunlight, protected from rain and snow. Drying takes one to three years depending on the type of wood and weather conditions.
Why do you need to dry firewood?
If the wood has a lot of residual moisture, it will only burn incompletely. In this case, combustion produces substances that can damage the environment and the heating system. For example, acetic acid is increasingly forming, which, together with other combustion residues, attacks the fireplace and chimney. Since significantly more soot is deposited when damp wood is burned, the stove pipes may become clogged and shiny soot can form, which can lead to dangerous soot fire.
Last but not least, the energy yield drops to a third because the water in the wood first has to be evaporated. So the wood is essentially drying in the oven, which wastes fuel unnecessarily and increases costs.
How can wood be dried?
Wood drying is usually done by storing it correctly outdoors. Proper storage is also important to prevent mold and rot. It also prevents pests such as house beetles or sapwood beetles from nesting.
The storage area
This should be such that no additional moisture gets to the wood. Therefore, pay attention to the following points:
- Air supply: The air should also reach the back of the firewood. This means that no moisture can collect anywhere that could lead to mold or rot.
- Sunlight: If sunlight reaches the wood pile, the drying effect of storage is increased. The residual moisture evaporates more quickly.
- Protection from weather influences: The firewood should not be exposed to rain and snow, as this allows additional moisture to penetrate.
The following is well suited for drying wood:
- A house wall facing south or southwest. Be sure to stack the wood 15 centimeters back so that the back of the stack is also ventilated.
- It is ideal if the fuel is protected from above by a sloping roof.
- Alternatively, you can stack the wood to dry in a traditional pile, a free-standing wood pile. The special shape allows the water to drain away while the heating material is dried by the sun on nice days. An optional roof protects from the weather from above.
However, the cellar or a closed garden shed is unsuitable for drying. The air exchange in rooms is far too low and the wood that is still damp inevitably begins to rot or mold. For the same reason, you should make sure to cover the pile with a tarp.
How long does it take to dry?
This cannot be answered in general terms, as weather conditions play a major role in air storage. Depending on the type of wood, the outdoor drying process takes about two to three years. Under optimal conditions, the heating material can even be used after a year.
Tip
The wood to be dried should also be protected from moisture penetration from below. Therefore, stack it on an area protected by stones (€24.00 on Amazon), Euro pallets or a tarpaulin made of pond liner.
