A Deep Dive into Hardwood Firewood: Species, Characteristics & Burning Tips

Certainly Wood is committed to providing the highest quality firewood for your home. Our premium kiln-dried hardwood logs are sourced from sustainable woodland within Britain and Europe. This ensures consistent quality, optimal dryness, and a superior burning experience. 

However, whilst all firewood species, if dried to below 20% moisture content, will burn well, it is important to note that they all have different characteristics that affect how your fire is managed. Some species are really easy to light, and establishing the fire is really simple, but others require a little more effort to get the fire going. However, once established, it will provide a longer-lasting fire.

Over the last few years, the UK has seen an abundance of ash firewood on the market, making it readily available and familiar to consumers. Ash has always been regarded as the ‘king of firewood’ and firewood poems say it’s so named because you can burn it ‘green’. Ignore this at your peril as no firewood should ever be burnt ‘green’ but it is because it has a lower moisture content than all other hardwoods when fresh cut, that the traditional poems say this.

We are now seeing a decline in the availability of ash firewood and there will gradually be more of the denser species such as oak and beech.

Here, we take you through our main species, how to identify them in your delivery, and therefore how to manage your fire.

Ash

The King of Firewood: Ash is popular for those seeking an easy-to-manage fire with a calorific value of 19 MJ/kg. It burns well but a little faster than the denser woods and has a characteristic white flesh colour on the split side.

Pros:

• Quick-lighting: Easy to ignite, ideal for easier fire lighting.
• Bright flames: Produces a cheerful and visually appealing fire.
• Good for smaller fires: Suitable for smaller fires or when a shorter burn time is desired.

Cons:

• Burns slightly quicker than oak, beech and hornbeam.

 

 

 

 

 

Oak

Beech

 

The Steady Burner: Beech performs similarly to oak, providing a calorific value of 17-19 MJ/kg and a long burn time. It produces a gentle, even heat with a bright flame. It's also a good choice for cooking over an open fire as it has low-spitting tendencies.

Pros:

• Even heat: Provides consistent warmth without intense bursts.
• Long burn time: Beech is a dense firewood that will burn for a long time.
• Bright flames: Creates a visually appealing fire.
• Good for cooking: Its steady heat makes it suitable for cooking over an open fire.

Cons:

• Can be difficult to light: Beech wood's density can make initial lighting challenging; however, as long as you're using Ready to Burn approved logs, there should be no issue starting a fire with smaller beech logs.
• Tip . Always maintain a good hot base to the fire, otherwise, if you let it die down too far, the next log will struggle to burn. You are likely to need the stove vents open for longer to get this hot base.

 

Hornbeam

The Ironwood: Hornbeam is incredibly dense, earning it the nickname "ironwood." It boasts an exceptionally high calorific value (around 20-22 MJ/kg) and burns incredibly slowly, providing extremely long burn times.

Pros:

• Extremely high heat output: Provides intense and long-lasting heat.
• Long-lasting: Burns for an extended period, minimising the need for frequent replenishment.
• Dense and durable: Ideal for long-term storage.

Cons:

• Difficult to light: 

Hornbeam is extremely dense, making it one of the most challenging woods to ignite. 

Tip: - It is vital to use smaller logs to start the fire, or if you have a less dense wood such as ash, light the fire with this, build the base, then add the hornbeam, but ensure a good hot base to the fire at all times. You are likely to need the stove vents open for longer to get this hot base.

 

Silver Birch (Not A Certainly Wood Species)

We provide information on this species because it is commonly found in supermarkets and garage forecourts and is sourced from Latvia and Lithuania, where this species dominates.

Silver Birch, while classified as a hardwood, offers a slightly different burning profile. With a calorific value typically ranging from 15 to 17 MJ/kg, it provides a good level of heat output, but it burns 20-25% faster than denser hardwoods like oak, beech and hornbeam, requiring more frequent replenishment.

Pros:

• Easy to light: Very simple to light a fire, providing good, quick heat
• Attractive wood: The bark is characteristically white/silver in colour and easily peels off in flakes.

Cons:

• Faster burn time: Requires more frequent replenishment than denser hardwoods; therefore, you need 20-25% more wood for the same heat.
• May produce more smoke: Can produce slightly more smoke than some denser hardwoods.

 

 

The Science Behind The Burn

• Density Matters: Denser woods like oak, beech, and hornbeam contain more wood fibres per unit volume. This translates to a higher calorific value, which releases more heat energy during combustion.
• Slower Burn: The dense structure of these woods slows down the combustion process. This results in a longer and more sustained burn, providing consistent heat over an extended period.

Lighting Challenges & Solutions

Lighting dense woods requires more thought:

• Top-down Method: All stove manufacturers and distributors now recommend this simple method. Fundamentally, it ensures the flame is at the top of the fire after lighting, which heats the flue faster, which in turn gets the fire drawing quicker.  There are two options:

a)     Our recommendation:  Place two small logs side by side on the grate of your woodburner. Place a KindleFlamer in the channel between the logs. Place one or two smaller logs across the KindleFlamer, then light.

b)     Place two small logs side by side. Stack 6-8 sticks of kiln-dried kindling in a Jenga formation and place one Flamer in the middle. Add two small logs at an angle over the kindling.

• Patience is Key: Don't rush the process. Allow the kindling to ignite properly before carefully adding larger pieces of wood. 
• Refuelling: When refuelling with oak, beech, or hornbeam, it's important to add logs before the fire burns down too low and the flame disappears.  Criss-cross the logs across the fire, ensuring good air flow between them.
• Airflow: Air provides oxygen, so the fire burns faster with more air and slower with less. This principle is essential throughout the burning process. When initially lighting a fire, especially with denser species like oak or beech, it's recommended to open the woodburner vents fully to allow maximum airflow. This helps to ignite the kindling quickly and establish the fire. Once the flames are well-established and the wood is burning steadily, you can gradually reduce the airflow by adjusting the vent settings. This controlled airflow ensures a more efficient and longer-lasting burn, maximising heat output while minimising smoke production.

What To Expect In Your Certainly Wood Delivery?

To help our customers understand the origin of their wood products, we have made some changes to our packaging.

For bulk bags, the presence of the "Grown in Britain" logo on the front of the bag indicates that the wood originated in the UK. If there is a green square on the bulk bags, this means that the wood has been sourced from Europe.  All imported bulk bags will primarily contain oak, beech, and hornbeam as the main species.

Regarding the small plastic bags, if they are heat-sealed, the wood inside comes from Britain. Conversely, if the bags are stitched, they are sourced from Europe.