Wood burning stoves are a fantastic way to heat your home, offering a cosy atmosphere and efficient heating. However, not all wood is suitable for burning. Using the wrong type of wood can lead to poor heat output, excessive smoke, and even damage to your stove. Within this article, I’d like to show you exactly what wood to use and how to check wood is properly seasoned. I’ll also talk about storing wood correctly so that you can get the best heat output from your log burning stove.
Table of Contents
Seasoned Wood vs. Green Wood: What’s the Difference?
Understanding the difference between seasoned wood and green wood is crucial for efficient and safe wood burning in your log burning stove. Here’s a breakdown of their key differences:
Seasoned Wood
Seasoned wood is firewood that has been cut, split, and left to dry for at least 6 to 24 months. This drying process reduces the moisture content of the wood to 20% or less, making it ideal for burning. Seasoned wood can also be dried in a kiln, known as kiln-dried wood, which can speed up the seasoning process significantly.
Characteristics of Seasoned Wood
- Low Moisture Content: Seasoned wood has a low moisture content, ensuring it burns efficiently with minimal smoke and creosote buildup.
- Appearance: It often has cracks and splits at the ends, a darker colour, and loose bark.
- Weight: Lighter than green wood due to the reduced water content.
- Sound: Produces a sharp, ringing sound when two pieces are banged together.
- Heat Output: Burns hotter and longer, providing more consistent heat.
Benefits of Seasoned Wood
- Efficiency: Provides better heat output and is more energy-efficient.
- Safety: Produces less creosote, reducing the risk of chimney fires.
- Convenience: Easier to ignite and maintain.
Green Wood
Green wood refers to freshly cut wood that has not yet had time to dry. It typically has a high moisture content, often exceeding 50%. This type of wood is not suitable for use in a log-burning stove or any other type of fire.
Characteristics of Green Wood
- High Moisture Content: Contains a significant amount of water, making it difficult to ignite and maintain a steady burn.
- Appearance: Lacks the cracks and splits seen in seasoned wood and usually retains its bark tightly.
- Weight: Heavier than seasoned wood due to the high water content.
- Sound: Produces a dull thud when two pieces are banged together.
- Heat Output: Burns cooler and produces more smoke and creosote.
Drawbacks of Green Wood
- Inefficiency: Less efficient in terms of heat output, requiring more wood to achieve the same level of warmth.
- Safety Risks: Produces more creosote, which can accumulate in the chimney and increase the risk of chimney fires.
- Difficulty: Harder to ignite and keep burning, requiring constant attention.
Seasoned vs. Green Wood
Choosing seasoned wood over green wood for your log burning stove is essential for optimal performance. Seasoned wood offers better efficiency, higher heat output, and enhanced safety, making your wood burning experience safer, more enjoyable and hassle-free.
Moisture Content
The most critical factor in determining the suitability of wood for burning is its moisture content. Ideally, firewood should have a moisture content of 20% or less. Here’s how to check:
Moisture Meter and Powerful Batteries
The most accurate way to measure moisture content is to use a moisture meter with a good set of batteries. Simply insert the prongs into the wood and read the moisture level. I expect a reading of 10-15% for my firewood, especially when buying from a reputable supplier.
I use a moisture meter like this RDINSCOS Moisture Meter, which provides accurate readings between 5% and 75%. The standard batteries provided with this unit aren’t very good, so I upgraded to something more reliable. These rechargeable aa aaa batteries from EBL provide extended life and improved performance for this moisture meter.
I’ve also upgraded to these batteries for my electric fire blower to get a bit more power out of the fan.
Visual Inspection
Seasoned wood often has cracks in the ends, is darker in colour, and feels lighter than green wood. Additionally, the bark should be easy to peel off.
Sound Test
Bang two pieces of wood together. Dry wood produces a sharp, ringing sound, while wet wood makes a dull thud.
Types of Wood and Their Burning Properties
Different types of wood have varying burning qualities, affecting heat output, burn time, and creosote production. Choosing the right type of wood can make your wood-burning stove more efficient and enjoyable. Here are some common types of wood and their burning properties:
Hardwoods
Oak
- Burning Properties: Oak is a dense hardwood that burns slowly and produces a steady, long-lasting heat. It is excellent for maintaining a consistent temperature over a long period.
- Pros: High heat output, long burn time, produces minimal smoke.
- Cons: Takes longer to season, can be difficult to split.
Ash
- Burning Properties: Ash burns well even when green, though it’s best when seasoned. It produces a steady flame and good heat.
- Pros: Easy to split, seasons quickly, burns cleanly.
- Cons: Availability may vary by region.
Cherry
- Burning Properties: Cherry wood burns steadily with a moderate heat output. It is renowned for producing a sweet, pleasant aroma when burned, making it a favorite for wood-burning stoves and fireplaces.
- Pros: Provides a good, consistent heat that is suitable for maintaining a comfortable room temperature, a delightful, sweet scent, burns cleanly, producing less smoke and fewer pollutants compared to some other types of wood.
- Cons: While it provides steady heat, cherry wood doesn’t burn as long as denser hardwoods like oak or ash. Depending on your location, cherry wood may be less readily available and can be more expensive.
Beech
- Burning Properties: Beech is another dense hardwood that burns hot and long. It produces a clean burn with minimal smoke.
- Pros: High heat output, long burn time, burns cleanly.
- Cons: Requires thorough seasoning, can be tough to split.
Softwoods
Pine
- Burning Properties: Pine ignites quickly and burns fast, making it ideal for kindling. However, it produces more creosote, which can build up in the chimney.
- Pros: Easy to ignite, readily available, great for kindling.
- Cons: Burns quickly, high creosote production, lower heat output.
Spruce
- Burning Properties: Spruce burns quickly with a bright flame. It is useful for starting fires but not for long-term heat.
- Pros: Quick ignition, bright flame, good for kindling.
- Cons: Burns fast, produces more creosote, lower heat output.
Fir
- Burning Properties: Fir is another softwood that burns quickly and is best used for kindling. It produces a pleasant aroma but also more creosote.
- Pros: Easy to start, aromatic, good for kindling.
- Cons: Burns fast, higher creosote production, lower heat output.
Wood Type Summary
Choosing the right type of wood for your log burning stove is essential for optimal performance. Hardwoods like oak, ash, cherry, and beech offer high heat output and long burn times, making them excellent choices for sustained heating. Softwoods such as pine, spruce, and fir are great for kindling due to their quick ignition but should be used sparingly to avoid excessive creosote buildup. Understanding these properties will help you make the best choice for efficient and safe wood burning.
Contaminants
Wood that has been painted, stained, or treated with chemicals should never be burned in a stove, as it can release toxic fumes and damage the stove. Similarly, avoid burning wood with mold or fungus, as these can also produce harmful emissions when burned. In addition to health hazards, burning contaminated wood can lead to the accumulation of toxic residues in your stove and chimney, increasing the risk of chimney fires and reducing the efficiency of your heating system. Always ensure your firewood is clean and free from any chemical treatments or biological contaminants to maintain a safe and effective wood-burning experience.
Wood Size
Ensure that the wood pieces are the appropriate size for your stove. Logs should fit easily into the stove without forcing. For our 5kW log burning stove we tend to stick with firewood that is typically, pieces that are 8 to 12 inches (20 – 30cm) long and about 3 to 6 inches (7 – 15cm) in diameter are ideal.
You can measure your own log burner and choose the right size wood. For example, if your stove is 50cm wide, avoid wood that is more than 45cm long. The door opening will also dictate the size of wood you can use. Most firewood suppliers will sell chopped wood no longer 28cm.
Storage Conditions
Proper storage conditions are crucial for maintaining the quality of firewood. Investing in a good log store is essential to protect the wood from the rain and ensure drying is achieved effectively.
- Elevate: Store wood off the ground to prevent moisture absorption.
- Cover: Use a tarp or a wood shed to keep wood dry but ensure adequate ventilation.
- Location: Store wood in a sunny, windy location to facilitate drying.
Take a look at some of these great log stores or build your own log store with this step-by-step guide.
Conclusion
Checking if wood is good for burning in a log burning stove involves assessing its moisture content, type, seasoning time, absence of contaminants, size, and storage conditions. By following these guidelines, you can ensure efficient, safe, and enjoyable wood burning in your stove. Remember, using well-seasoned, appropriate wood not only enhances your stove’s performance but also extends its lifespan and reduces maintenance needs.
