Ready to Burn Firewood: What It Means & Why It Matters

‘Ready to Burn’ firewood is legally certified to contain a moisture content of 20% or below, making it immediately safe and efficient to burn in home appliances. Administered by Woodsure and supported by UK air quality regulations, this certification guarantees that your firewood lights easily, burns hotter, produces minimal smoke, and protects your stove and chimney from tar buildup.

As the pioneer of kiln-dried logs in the UK, Certainly Wood was exceeding the current legislation levels long before they came into force. Find out more about the ‘Ready to Burn’ logo and why you should look for it when you buy firewood…

In the meantime, browse our full range of ‘Ready to Burn’ kiln-dried logs here. 

Why the moisture content of firewood matters 

The moisture content of your firewood determines how much heat actually reaches your room. When logs contain more than 20% water, your fire is forced to waste its initial energy boiling off trapped moisture before it can produce noticeable heat. This means:  

• A much lower heat output: Up to 50% of the log's thermal energy is lost simply evaporating internal water.
• More smoke and air pollution: Incomplete combustion releases dense black smoke, fine particulates and unburnt volatile gases into the atmosphere.
• Difficulty lighting: High moisture makes fires frustratingly difficult to light and keep burning without endless kindling and firelighters. 
• Blackened stove glass: Steam mixed with unburnt tars condenses on cold stove glass, leaving stubborn black creosote deposits that block your view of the flames.
• Increased creosote and tar build-up: Condensed moisture coats the inside of your flue with highly flammable creosote, significantly increasing the risk of chimney fires and costly appliance damage.

Choosing ‘Ready to Burn’ certified logs (under 20% moisture) eliminates these issues, delivering immediate, clean heat while keeping your chimney clear and your stove glass crystal clear. 

What’s the ideal moisture content for firewood?

For safe, efficient heating, firewood should always have a moisture content below 20%.

Anything above this threshold is considered unseasoned or ‘wet,’ leading to sluggish combustion, excessive smoke, and wasted fuel. To get the best performance from your appliance, aim for the following moisture targets:

Why kiln-dried wood beats air-seasoned wood

While naturally air-seasoning wood in a stack can take up to two years, and remains at the mercy of unpredictable humid weather, kiln drying uses precise climate-controlled heat.

This process bakes moisture out from the core of every log, ensuring consistent, ultra-low moisture levels through the entire wood pile, every single time you light up. Read our article about kiln-dried logs vs seasoned logs for more information.

So, were you prepared and are you sure that you now comply?

How can you tell if firewood is ‘Ready to Burn’ certified?

 

 

 

 

 

 

The easiest way to tell if firewood is ‘Ready to Burn’ is to look for the certification logo on the packaging. Approved suppliers will also display:

• A registered supplier number
• Woodsure certification details
• Clear moisture information

At Certainly Wood, all of our kiln-dried logs are ‘Ready to Burn’ certified for immediate use. 

This means that it burns cleaner, more efficiently, and with lower emissions. If you want to learn more about why moisture content matters, read our guide to the benefits of kiln-dried logs or discover what wet wood is and why you shouldn’t burn it.

‘Ready to Burn’ FAQs

Is ‘Ready to Burn’ a legal requirement?

Yes, in England it is a legal requirement for firewood sold in volumes under 2m³ to be Ready to Burn certified. This applies under the Air Quality (Domestic Solid Fuels Standards) (England) Regulations 2020, part of the government's wider Clean Air Strategy. Local authorities are responsible for enforcement, and selling non-compliant fuel, or burning it in the wrong appliance within a smoke control area, can result in fines. Scotland, Wales, and Northern Ireland have their own separate air quality rules, so requirements may differ. 

 

Do ‘Ready to Burn’ regulations only apply to firewood?

No, ‘Ready to Burn’ regulations also apply to kindling and compressed wood heat logs. These products must also be dried to a moisture level below 20% to meet certification requirements. However, some heat logs that are not made entirely from pure wood may be exempt from the scheme.