What Wood to Burn: 6 Best and 6 Worst Options for Your Burner

Millions of people in the UK are burning wood that should never be burned.

See black smoke coming from your neighbour’s chimney? Chances are, they’re burning wet wood they’ve found somewhere in the forest or their garden. This is highly problematic. Why?

Top Reasons You Should Never Burn Wet Wood

• It's bad for your health. When burned, wet wood releases thousands of harmful gases into the air you breathe. Many of these are known to cause health problems (including cancer) for both pets and people.

• It's bad for your burner. These gases condense in your chimney and flue as tar and creosote. This is not only damaging to your appliance (leading to costly repairs) but can also cause a chimney fire in the future.

• It's bad for the health of the environment. Burning wet wood is also very damaging to our planet due to the amount of particulate matter released into the air. It is also the prime reason wood fuels have a boogeyman reputation in environmentalist circles.

• It supplies very little heat. And to top it all off, wet wood doesn’t heat all that well because a lot of energy is wasted turning water into steam (which is the black smoke you see coming out of the chimney).

Wet wood is just one of the many problematic types of wood fuel that people in the UK routinely burn. Other types include pallets and old wood furniture, both of which you can get for free on places like Facebook marketplace. Rotten wood, found wood, and driftwood, which people often gather in their gardens or the forest. There are also seemingly innocuous options, such as unseasoned wood, that you can actually find legally for sale in certain parts of the country.

On the other hand, if you burn proper, Defra-approved wood heating fuel, then you will be happy to know that your heating choice is clean, efficient, and incredibly eco-friendly. In fact, the United Nations sees well-managed wood heating as a sustainable, eco-friendly option that is preferable to coal and gas. 

With the use of wood heating fuels being on the rise in all of Europe, it’s imperative that you and the people around you know which types are inefficient, unsafe, or even toxic to burn. 

So, what is the best type of wood to burn in your log burner? Can you burn rotten wood? Is burning wood pallets or old furniture a good idea? Can you burn the branches from your garden? And what wood is toxic to burn?

By the time you finish reading this article, you’ll know the answers to these questions and many, many more.

You Might Also Like:

Which UK Supermarket Sells the Best Logs?

All You Need to Know About Wood Moisture Meters

How to Maximise Heat From a Log Burner

6 Worst Woods to Burn in Your Wood Burner

Before we tell you the best types of wood you should be burning in your stove, let’s take a look at the woods you should never burn. We’ll also explore the precise reasons that make them a bad choice for your burner.

Treated Wood (Toxic, Cancerogenic, Health & Environment Hazard)

Can you burn treated wood? Absolutely not. Burning treated wood is extremely hazardous and should be avoided at all costs.

When burned, treated wood releases a toxic mix of chemicals. These can include heavy metals, volatile organic compounds (VOCs), and carcinogenic dioxins. Some of these may cause immediate health issues like respiratory irritation, which is the best-case scenario because it will at least make the person reconsider using treated wood. But most treated wood doesn’t cause immediate damage. Instead, it silently contributes to long-term risks, including severe organ damage and cancer. By the time you find out about the damage done to you, it’s often already too late.

Chemical fumes from treated wood also corrode chimneys, increase creosote buildup, and increase the risk of chimney fires (read our full article on the dangers of creosote). The environmental impact of burning treated wood is also significant. Air pollution from such fires is known to harm ecosystems. But that’s not the end of it. When disposed of improperly, the ash from the burning of treated wood will contaminate the soil and groundwater around your home.

Prevalence: It might come as a surprise, but many people in the UK (including people commenting on Lekto’s Facebook posts) are burning treated wood in their stoves. This includes wooden pallets, painted skirting boards, old furniture, and offcuts from DIY projects.

Rotted Wood (Infests Your Home With Mould and Fungal Spores)

While rotted wood will, indeed, burn, the fire will be highly inefficient, producing minimal heat and excessive smoke. But that isn’t even the real reason that makes us put rotted wood at the very top of our list.

Burning rotting wood releases spores into your home and the air you breathe.

Rotten wood is almost always colonised by mould and fungi, which reproduce with microscopic spores. When burned, these spores can become airborne and spread. This means that not only are you and your loved ones breathing in spores, but the fire will actually help the mould spread throughout your house. Avoid it entirely.

Prevalence: You may be surprised, but a lot of people in the UK are heating their homes with mouldy, rotten wood. How do we know this? Empirical data. Questions like can you burn rotten wood and will rotten wood burn are some of the most widely asked on Google UK.

Plywood and Chipboard (Releases Toxic Fumes Into the Air)

People sometimes ask our customer support staff whether it’s okay to burn plywood and chipboard. The thinking is that plywood and chipboard are made of sawdust. And what else is made of sawdust? Wood briquettes! So, burning plywood is the same as burning a briquette, right?

Wrong. Plywood and chipboard should never be burned in a log burner. This is because, unlike wood briquettes, plywood and chipboard are bound together not with natural lignin that is contained in the wood but with chemical adhesives.

These adhesives release toxic fumes like formaldehyde and dioxins when ignited. As a result, you get serious health risks, including respiratory issues and harm to the environment by releasing these toxic compounds into the air.

And like with treated wood, plywood and chipboard will also damage your heating systems by causing creosote buildup in chimneys (leading to you needing to hire a chimney sweep more often). This, in turn, increases the risk of fires.

Avoid it at all costs.

Driftwood (Releases Chlorine Gas Into the Air You Breathe)

But what about burning dried driftwood? It’s not treated in any way, and your wood moisture meter says it’s perfectly dry. Surely this makes it perfectly safe to burn indoors, right?

No, it doesn’t. Driftwood should never be burned because it absorbs salt from seawater. And what’s wrong with it being impregnated with salt? 

The fact that such wood releases harmful chlorine gas and dioxins when ignited. These emissions are toxic to your health, contributing to respiratory issues and environmental pollution. Additionally, the salt can corrode and damage your open fire, wood burner, or chimney over time.

Wet Wood (Low Heat, Creosote Buildup, Risk of Chimney Fires)

Unseasoned logs, also known as green wood or unseasoned wood, is wood that is cut from a tree but not appropriately dried to moisture levels of under 20%. Unscrupulous sellers will advertise them to customers as a far cheaper alternative to traditional seasoned and kiln-dried logs.

A couple of years ago, the government had a crackdown on sellers of unseasoned logs, and it is now illegal to sell them in quantities of less than 2 cubic meters (see our article on Defra’s Ready to Burn initiative to learn more).

But what makes seasoned logs so bad that the government has to get involved?

While cheap, green, unseasoned wood is unsuitable for burning due to its high moisture content. When burned, wet wood has to release this moisture as steam, which leads to poor heat output. The moisture is released as steam, which condenses on your chimney and flue as creosote, which can lead to damage to your chimney and cause chimney fires.

Read our article on the importance of wood fuel moisture levels.

Pine (Good For Kindling, But Not Great For Making Logs)

Is burning pine wood toxic? No, it’s not. Will it make your chimney explode? Probably not. But does that mean it’s a good wood fuel option for your log burner? Also no.

While burning pine wood is not inherently toxic, but it’s still a softwood with a high resin content. This is problematic because it can produce excessive smoke and lead to significant creosote buildup in chimneys.

This being said, drying pine to extra low moisture levels (under 10%) will get rid of most of that resin and allow pine wood to burn cleanly. While achieving such low moisture levels is impractical for making logs, it’s pretty achievable for kindling.

In fact, pine is a perfect material for making kindling. It is easy to light and releases its heat quickly, which allows it to light even the most stubborn logs.

How sure are our experts of the quality of pine kindling? We’ve put our money where our mouth is. Lekto’s very own Premium Softwood Kindling is made from a mixture of kiln-dried pine and fir.

6 Best Woods to Burn in Your Fireplace (+1 Honourable Mention)

Now that we know what woods you should absolutely never burn let’s take a look at the best woods to burn in the UK. These are ranked from the most commonly recommended to move down to less recommended options. We’ll also include an honourable mention.

Ash Logs (The UK’s #1 Wood For Burning)

Ask any chimney sweep or other wood heating professional for a wood fuel recommendation, and chances are they’ll suggest kiln-dried ash logs. These logs are by far the most widely used and commonly recommended types of firewood in the UK. And for a good reason.

Ash is super easy to light, burns at a high temperature, has a steady heat output, and produces minimal smoke.

Unlike most woods, ash has a relatively low moisture content even when freshly cut, which makes it quite popular with people who have large amounts of land and can season their own logs.

If, however, you are a discerning customer who prefers the consistency of professionally kiln-dried logs, then you’ll be pleased to learn that ash responds very well to kiln-drying. 

Lekto’s premium Kiln-Dried Ash Logs often contain as little as 10%-15% moisture, which is above and beyond the standard set by Defra’s Ready to Burn Standard. This allows them to be super easy to light and burn extremely efficiently.

Read our stand-alone article about ash logs to learn more.

Oak Logs (Very Energy Dense, High Heat Output, Long Burn)

Favoured by firewood connoisseurs, oak is one of the densest hardwood firewood log types out there. It’s prized for its exceptional heat output and burn time, which makes it perfect for heating large rooms or in cold climates.

Its high heat output also makes it ideal for cooking purposes. In fact, it’s the only type of firewood you’ll find used in authentic Italian pizzerias. The high heat output is also great for searing steaks.

Its versatility and performance make it a favourite among firewood enthusiasts and chefs alike.

What are the drawbacks? Freshly cut oak is very dense and has a very high moisture content. This makes it unsuitable for seasoning in British climes. When buying oak, it’s always advisable to choose premium Kiln-Dried Oak Logs that are dried to a consistent moisture level in an industrial kiln. These will burn cleanly and efficiently.

Oak is also not the easiest type of wood to light, although you should have no difficult doing so if you use the top-down method. This method is not only fool-proof, but it also preheats your stove, chimney, and flue, which helps reduce particulate matter emissions.

Read our article on the Top-Down Fire Starting Method.

Birch Logs (Easy to Light, Beautiful Flame, Affordable)

Another popular type of firewood in the UK is birch. It’s very easy to light, ignites quickly, and produces very bright, vibrant flames that are beautiful to look at. Another popular feature is their affordable price. Birch logs are often markedly less expensive than oak and ash logs.

On top of this, birch logs are also aesthetically pleasing, which makes them a popular choice for decorative purposes. If you plan on using birch logs for this reason, make sure you use Kiln-Dried Birch Logs rather than the seasoned kind. This is because seasoned logs often house pests, fungi, and moulds. The high-heat kiln-drying process gets rid of this problem and makes the logs 100% safe to store indoors.

This being said, they burn at a somewhat lower temperature than oak and do not last as long.

Beech Logs (Long Lasting Heat)

Beech is another dense hardwood tree. Much like oak, it’s highly valued for its ability to burn hot and clean with minimal smoke. It provides steady, long-lasting heat, making it an excellent choice for sustained fires in wood stoves and fireplaces. 

Once properly seasoned, beech delivers consistent, reliable performance. It’s not as popular as oak, but it can be a good option if you can get it at a lot price.

Hickory Logs (Hot Flames, Clean Burn)

Hickory is a hot-burn firewood type whose high density ensures a steady, prolonged burn. 

Hickory produces a clean flame with minimal smoke. It produces a pleasant aroma when burned, which makes it a good option for summer BBQing and smoking meats. Some people also swear by it for searing steaks, although neutral, hot-heating oak will be more popular for this use case.

Cherry Wood Logs (Sweet Aroma, Minimal Smoke)

Despite what many people think, burning cherry wood is not toxic and is perfectly safe. In fact, cherry is a popular choice for open fires and wood stoves.

When burned, cherry wood produces a pleasant, slightly sweet aroma. This can add a cosy atmosphere to any room, making it a popular option for guest houses.

It offers moderate heat output and burn time, being very similar to birch in this regard. In terms of burning performance, it burns cleanly, with minimal smoke, and produces bright, visually appealing flames. While it doesn’t burn as long as denser hardwoods like oak, cherry is a versatile and enjoyable firewood option, especially when well-seasoned to enhance its performance and fragrance.

Read our stand-alone article about cherry wood to learn more.

Honourable Mention: Eucalyptus Logs (Can Be Good Once Dried Properly)

Our honourable mention is Eucalyptus. It’s a fast-growing hardwood known for its ability to burn hot and deliver steady, long-lasting heat. Its high density makes it an efficient fuel source, ideal for wood stoves and fireplaces.

However, the reason we cannot put it on our Top 6 list is its high sap content when freshly cut. This sap can lead to excessive smoke, difficulty igniting, and increased creosote buildup. This makes it somewhat similar to a softwood-like pine.

This being said, properly seasoned or kiln-dried eucalyptus can make for a very good option, provided you know what you are buying.

Read our stand-alone article about eucalyptus wood to learn more.