How to treat wooden logs

You can’t just throw any old wood into your log burner.

We have looked at the dangers and unsuitability of burning untreated or ‘green’ firewood - Green Wood Why You Should Avoid It previously. Some of the negatives of burning this type of wood include:

• Its high moisture content makes it unsuitable for burning
• Burning untreated logs has been linked to some health conditions

In fact, the government has started phasing out this type of wood for sale in England in February 2021.

Instead of burning green wood, how are logs treated and seasoned so they can be used safely and efficiently in your wood burner?

Kiln-dried logs

Kiln-dried logs are among the most common types of treated firewood you can buy.

Kiln drying firewood results in low moisture content (usually under 20%). The low moisture contributes to a slow, clean burn that is pretty environmentally friendly.

Logs treated this way are put into a kiln and kept at a steady temperature between 80-90°C. This process can take up to four days for enough moisture to be removed from the firewood.

Both our ash and birch kiln-dried logs are treated this way. It results in firewood that will burn efficiently and doesn’t have any of the negative impacts of untreated or greenwood.

Seasoned logs

Another option to treat wooden logs is to season them.

This is a much longer process as it can take between 12 - 24 months, although some softwoods such as fir and cedar can be seasoned in 6 months. The logs are left outdoors in a place that gives them decent exposure to both the sun and the wind. The sun will dry the logs out while the wind will blow excess moisture away.

Seasoning logs result in low moisture content, the same as the kiln-dried logs; however, it takes longer.

How to treat logs for your wood burner

If you plan on treating logs yourself, these are the two options available.

Although not everyone has access to a kiln, the best way to treated logs is to season them, even if it will take a long time.

If you are going to treat your own logs by seasoning them and ensuring they are equipped to burn evenly, effectively, and cleanly, you should:

Chop the logs into smaller pieces

Smaller logs should season a bit quicker than larger wood. The logs should be around 6 inches in length, and this not only helps with the seasoning process but also means they will fit into most log burners.

Stack them correctly

Ensure that the logs you are treating aren’t tightly packed together, as this will make it difficult for them to dry out, and the moisture won’t escape properly. Instead, stack them loosely together while ensuring they aren’t sitting on the ground (a pallet or a log store is the best option).

Leave them to season

As we mentioned, the seasoning process can take between 12 - 24 months for hardwoods such as ash and birch and over 6 months for softwoods.

If you are using softwood, start the process in the spring (around April time), and they will be ready for the cold weather coming in later in the year.

Treating logs by seasoning is a long process. However, it is environmentally friendly and rewarding, especially when you light up your fire with logs you have treated yourself.