The Complete Guide to Buying Firewood in the UK
Buying firewood well comes down to a few simple rules: choose a hardwood, make sure it's dried below 20% moisture, pick the right log size for your appliance and store it properly. Get those right and every fire burns hotter, cleaner and cheaper.
This guide covers everything you need to know to buy firewood in the UK, the best wood to choose, how much you'll need for winter, what to avoid, and how to store and light it. At Calido, we supply kiln dried hardwood logs to homes across the UK, and we've written this to help you buy with confidence, whichever supplier you choose.
Contents
- Part 1: Buying firewood
- Part 2: Kiln-dried vs seasoned
- Part 3: How much firewood you need (and what it costs)
- Part 4: Logs vs Briquettes
- Part 5: How much firewood do I need?
- Part 6: Storing firewood
- Part 7: Lighting fires
- Part 8: What is Ready to Burn?
- Part 9: Quick buying checklist
Part 1: Buying Firewood
What's the best firewood to buy?
The best firewood to buy is hardwood logs with a moisture content below 20%, certified under the Ready to Burn scheme. For UK homes, kiln dried hardwood logs are the most reliable choice because they're dried under controlled conditions and perform consistently. Dense species such as oak, ash, beech and birch give strong heat, a steady flame and a cleaner burn.
The "best" firewood does depend on how you'll use it:
| Use | Best firewood type | Why |
|---|---|---|
| Wood burners | Kiln-dried hardwood logs | Clean, efficient, long-lasting |
| Open fires | Dense, chunky hardwood logs | Slower burn, strong flame |
| Pizza ovens | Thin-cut kiln-dried hardwood | Fast heat, easy to control |
| Firepits | Dry mixed hardwood | Good flames, less smoke |
| BBQs | Kiln-dried hardwood or charcoal | Cleaner cooking heat |
Expert advice from Calido: For the cleanest, most efficient fire, choose hardwood logs below 20% moisture and store them correctly after delivery. The drier the wood, the more heat ends up in your room rather than going up the chimney as smoke.
Which firewood burns the longest?
The firewood that burns longest is dense hardwood, particularly oak. Its high density means it releases heat slowly and steadily, which makes it ideal for larger stoves, open fires and overnight burning.
Burn time isn't only about species, though. It also depends on moisture content, log size, stove efficiency and airflow. A dry oak log will far outlast a damp one, and a well-managed stove will stretch a fire longer than one with the vents wide open.
Which firewood gives the most heat?
The firewood that gives the most heat is dry, dense hardwood - oak, ash and birch are the standout performers because they have a high calorific value. But moisture content is just as important as species: wet wood wastes a large share of its energy boiling off water before it can produce usable heat. A dry, less-dense log can easily outperform poorly seasoned oak.
Hardwood vs softwood: which is better?
Hardwood is better for heating because it burns longer and produces more sustained heat, while softwood lights quickly but burns through faster. Hardwood comes from broadleaf trees (oak, ash, beech, birch); softwood from conifers (pine, spruce, fir).
- Hardwood - slower burn, stronger embers, longer heat. Best for wood burners, open fires and home heating.
- Softwood - fast ignition, shorter burn. Ideal for kindling and getting a fire started.
Softwood is perfectly safe to burn if it's properly dried, it's just better suited to lighting fires than sustaining them. The golden rule applies to both: whatever the species, it must be dry.
What's the best firewood for wood burners?
The best firewood for wood burners is kiln dried hardwood below 20% moisture, especially oak, ash, beech and birch. Oak is ideal for long burns, ash is a strong all-rounder, birch lights easily for fast heat, and beech gives a steady, reliable burn.
Wet or poorly seasoned logs work against a stove: they blacken the glass, create more smoke and build up tar and soot in the flue. For a wood burner, look for Ready to Burn certification, below 20% moisture, hardwood species and a log size that fits your firebox.
What's the best firewood for open fires?
The best firewood for open fires is dense kiln-dried hardwood in wider diameters, because it gives a steadier, longer-lasting flame. Open fires lose more heat up the chimney than stoves and offer less airflow control, so a mix of chunky hardwood log, with a few smaller pieces to get going, works best.
What firewood is best for pizza ovens?
The best firewood for pizza ovens is thin-cut, dry hardwood that's low-spitting, such as ash or beech. Pizza ovens need fast, clean, controllable heat, so smaller split logs beat large chunks; they bring the oven up to temperature quickly. Good pizza-oven wood is kiln-dried, hardwood, below 20% moisture and free from any chemical treatment.
Which firewood is best for firepits and campfires?
The best firewood for firepits and campfires is kiln-dried hardwood, because it gives better flames, stronger heat and less smoke. Outdoor fires are often about atmosphere as much as warmth, so flame quality matters; birch lights well, while ash and oak burn cleanly. Wet wood is the usual reason a firepit turns smoky.
Oak vs ash: which is better?
Oak is better for long burns; ash is the better all-rounder that lights more easily and gives reliable heat.
| Feature | Oak | Ash |
|---|---|---|
| Burn time | Long | Medium-long |
| Heat output | Very high | High |
| Ease of lighting | Needs kindling | Easy |
| Best for | Long & overnight fires | Everyday stove use |
Birch vs beech: which is better?
Birch is ideal for quick heat and easy lighting; beech is better for steady, longer-lasting warmth.
| Feature | Birch | Beech |
|---|---|---|
| Burn speed | Faster | Medium |
| Heat output | Medium-high | High |
| Ease of lighting | Very good | Good |
| Best for | Quick heat, firelighting | Steady heat, cooking |
What size logs should you buy?
The best log size depends on your appliance. For most UK wood burners, 25cm logs are a practical standard that fits the majority of stoves. Larger open fires may suit 35cm or longer, while pizza ovens and small stoves need shorter, thinner logs.
| Appliance | Recommended log size |
|---|---|
| Standard wood burner | Around 25cm |
| Small stove | Shorter logs |
| Open fire | Chunkier mix of sizes |
| Pizza oven | Thinner, split logs |
| Firepit | Mixed sizes |
Logs that are too big are hard to light and restrict airflow; logs that are too small burn through quickly.
What firewood should you avoid?
Avoid wet, mouldy, painted, varnished or chemically treated wood. Never burn painted or treated timber, MDF or chipboard, pallets of unknown origin, driftwood, rotten logs or household waste; these produce harmful smoke and can damage your appliance. Always choose clean, dry, untreated firewood.
What are the most common firewood buying mistakes?
The most common mistakes are buying wet logs, choosing the wrong log size, misreading volume measurements, and storing logs badly.
| Mistake | Why it matters |
|---|---|
| Buying wet logs | More smoke, less heat |
| Logs too large | Harder to light |
| Ignoring moisture content | Lower efficiency |
| Comparing loose fill with stacked volume | Misleading price comparison |
| Storing in damp conditions | Ruins good firewood |
| Buying too late in winter | Limited availability |
Part 2: Kiln Dried vs Seasoned Firewood
If you've been buying firewood for a while, you'll have come across both kiln dried and seasoned logs. The difference matters more than most people realise, especially in Scotland where ambient humidity and rainfall make it harder for naturally dried wood to reach the moisture levels you need.
What is Seasoned Firewood?
Seasoned firewood is wood that has been cut and left to air-dry naturally, typically for 12-24 months. In ideal conditions- dry storage, good airflow, warm summers - seasoning can produce logs with moisture content below 20%. In Scotland's climate, this is significantly harder to achieve reliably. Wood left outdoors or in partially exposed storage often retains moisture above 25%, even after two full years.
The core problem with seasoned wood in Scotland is consistency. You can't tell by looking at a log whether it has dried properly. Suppliers selling 'seasoned' wood may mean anything from 'stored for six months' to 'properly dried for two years under cover'. Without a moisture meter, you have no way of knowing what you're getting.
What is Kiln Dried Firewood?
Kiln dried firewood is wood that has been dried in a purpose-built industrial kiln, typically at temperatures between 65-80°C for several days. The process removes moisture evenly and consistently throughout each log — not just from the surface. The result is firewood with a reliably low moisture content, typically between 10-20%, regardless of the season or weather conditions.
Because kiln drying is a controlled industrial process, every delivery from a certified supplier will perform the same way. There are no surprises, no wet logs hiding in the middle of a crate, and no need to store the wood for months before you can burn it. It arrives ready to use.
Why Moisture Content Matters
This is the key thing to understand: every unit of moisture in a log consumes energy to evaporate before the log can generate heat. A log at 30% moisture content produces significantly less usable heat than the same log at 15% moisture. You're effectively burning energy to boil water before getting any warmth from your fire.
|
|
Kiln Dried |
Seasoned (typical) |
|
Moisture content |
10–20% |
20–35% (variable) |
|
Ready to burn on delivery |
Yes |
Not always |
|
Heat output per log |
High |
Lower (energy lost to steam) |
|
Smoke production |
Low |
Higher — more particulates |
|
Stove glass blackening |
Minimal |
Common with damp wood |
|
Creosote / tar in flue |
Low risk |
Higher risk |
|
Legal compliance (post-2021) |
Yes (if certified) |
Only if below 20% |
|
Consistency |
High |
Variable |
|
✦ |
Since May 2021, UK regulations require that all firewood sold in volumes up to 2m³ must be Ready to Burn certified - meaning it must have a moisture content below 20%. All Calido firewood is Woodsure Ready to Burn certified and meets this standard on every delivery. |
The Scotland Factor
It's worth being direct about something: natural seasoning is harder in Scotland than in most of England. Longer, wetter winters, higher year-round humidity, and shorter warm summers all work against the seasoning process. This is one reason kiln dried logs have become the default choice for Scottish stove users far more quickly than in the south. The controlled drying environment removes the climate variable entirely. Your logs will be at the right moisture content regardless of whether we've had a dry summer or a typical Scottish one.
Part 3: Kiln Dried Logs vs Briquettes
Alongside our kiln dried logs, Calido sells a range of briquettes and heat logs — including Pini Kay briquettes, eco logs, and fire log briquettes. Many of our customers use both, combining logs and briquettes depending on the situation. This section explains the difference and helps you decide what's right for you.
What Are Wood Briquettes and Heat Logs?
Briquettes and heat logs are compressed wood products made from sawdust, wood shavings, or other timber by-products. They contain no additives, binders, or chemicals — the wood is simply compressed under high pressure, which causes the wood's natural lignin to bind the material together. The result is a dense, uniform fuel with very low moisture content, typically under 10%.
Pini Kay briquettes are the most common format — a cylindrical log with a characteristic hole through the centre that improves airflow and helps with even combustion. RUF briquettes are rectangular and slightly smaller. Our eco fire logs are a similar compressed format. All are Ready to Burn certified.
How Briquettes Burn Differently to Logs
The lower moisture content and higher density of briquettes means they burn differently to kiln dried logs in a few important ways:
-
They burn hotter per unit of weight — more energy is released per kilogram than from a standard log
-
They burn more slowly — a Pini Kay briquette can burn for 2-3 hours in a controlled stove
-
They produce very little ash — far less clearing out after each session
-
They don't produce the same open flame aesthetic as logs — more of a steady, consistent glow
-
They expand slightly as they burn — avoid overfilling your stove firebox
Logs vs Briquettes: Which Should You Choose?
|
|
Kiln Dried Logs |
Briquettes / Heat Logs |
|
Moisture content |
10–20% |
Under 10% |
|
Heat output |
High |
Very high per kg |
|
Burn time |
30–90 mins per log |
2–3 hours per briquette |
|
Flame aesthetic |
Open, natural flame |
Steady glow, less visible flame |
|
Ash produced |
Some |
Very little |
|
Storage space needed |
More |
Less — very compact |
|
Price per session |
Moderate |
Often lower per hour of heat |
|
Best for |
Everyday fires, flame aesthetics, pizza ovens, hot tubs |
Overnight burning, top-up heat, supplementing logs |
How Our Customers Combine Both
The most popular approach among Calido customers is to use logs and briquettes together rather than choosing one or the other. A common pattern is to light the stove with birch logs and kindling, enjoy the open flame for an hour or two, then add one or two briquettes before bed for sustained overnight warmth. In the morning, the embers are often still going.
For customers with limited storage space — particularly those in flats or urban homes in Falkirk, Stirling, or Glasgow — briquettes are often the primary fuel because they're far more space-efficient than bulk logs.
|
✦ |
Calido tip: If you're not sure where to start with briquettes, order a small quantity alongside your regular logs. Try adding a Pini Kay briquette to an established fire and notice how the burn time extends. Most customers who try them use both permanently after that. |
Part 4: How Much Firewood You Need (and What It Costs)
How much firewood do you need for winter?
Most regular wood-burner users in the UK get through around 3-4 cubic metres of kiln-dried firewood over a typical winter. The exact amount depends on how often you light the stove, whether it's a primary or secondary heat source, the size and insulation of your home, and how cold the winter is.
| Usage level | Approximate need |
|---|---|
| Occasional use | 1–2m³ per winter |
| Regular evening use | 3–4m³ per winter |
| Heavy / primary heating | 5m³+ per winter |
Wet wood throws these figures off, if logs are damp you'll burn noticeably more to get the same warmth.
How many briquettes do you need for winter?
| Usage level | Recommended quantity |
|---|---|
| Occasional use | Half pallet |
| Regular evening use | Full pallet |
| Heavy / primary heating | 2-4 pallets |
What's the cheapest way to buy firewood?
The cheapest way to buy firewood is usually in bulk, where the price per cubic metre is lowest. Crates and bulk bags work out better value than small bags or boxes because there's less packaging and a lower delivery cost per log. But cheapest isn't always best value; wet, badly sized or hard-to-store logs are a false economy. Compare firewood by usable heat, not just the upfront price.
Loose fill vs stacked: what's the difference?
Loose-fill firewood is measured when logs are tipped in loosely, leaving air gaps; stacked firewood is measured tightly arranged. A loose-filled cubic metre contains less actual wood than a stacked one because of the spaces between logs. When comparing suppliers, always check whether a quoted volume is loose-filled or neatly stacked, and compare bag or crate dimensions.
Part 5: Storing Firewood
How should you store firewood?
Firewood should be stored under cover, off the ground and somewhere well ventilated. Even kiln dried logs can re-absorb moisture if they're left in the rain or sat on damp ground. Good storage protects the low moisture content you paid for.
- Keep logs off the ground (a pallet or log store works well)
- Cover the top to keep rain off, but leave the sides open for airflow
- Don't seal logs tightly under plastic; they need to breathe
- Use the oldest logs first
Can kiln dried logs get wet?
Kiln drying removes moisture but doesn't make logs waterproof. Left uncovered in the rain or on wet ground, they can take moisture back on and become harder to light or mouldy. Store them under cover with airflow, and they'll stay ready to burn.
Can you store firewood in a garage?
Yes, a garage is a good place to store firewood as long as it's dry and has some ventilation. Keep logs raised off the floor, away from damp walls, and don't cover them tightly with plastic. If the garage is very damp, an outdoor covered log store with better airflow is a better bet.
Part 6: Lighting Fires
What's the best way to light a fire?
The best way to light a fire is the "top-down" method, using dry logs, natural firelighters and good airflow. It burns cleaner than lighting from the bottom because it warms the flue quickly and reduces smoke at the start.
- Place larger logs at the bottom
- Add smaller logs or kindling across the top
- Put a natural firelighter on top
- Light it and leave the vents open until the fire is established
Avoid newspaper, damp kindling or wet logs; they all make smoke and slow the fire down.
Do you need kindling?
You usually need kindling with standard firelighters to bridge the gap between the small flame and the logs, especially with larger or denser logs like oak, or in a cold room.
Part 7: What is Ready to Burn?
The Ready to Burn scheme is the UK's official certification for firewood and solid fuels, managed by Woodsure on behalf of DEFRA. It gives you confidence that the firewood you're buying has been independently tested and contains 20% moisture or less, helping it burn more efficiently and with less smoke.
Since 2021, firewood sold in quantities of less than 2m³ must meet Ready to Burn standards. Choosing certified firewood means you're buying logs that are ready to use straight away, without needing further drying or seasoning.
For homeowners, Ready to Burn certification offers several important benefits:
- Guaranteed moisture content below 20%
- Cleaner, more efficient burning
- More heat from every log
- Less smoke and fewer emissions
- Reduced tar and creosote build-up in your flue
- Easier lighting and a more consistent burn
At Calido, all of our kiln dried hardwood logs and wood briquettes are Ready to Burn certified, so you can be confident you're receiving fuel that's dry, efficient and ready to use from the moment it's arrives.
Part 8: Quick Firewood Buying Checklist
When buying firewood in the UK, look for dry, clean, untreated hardwood logs below 20% moisture. For most homes, kiln-dried Ready to Burn hardwood is the most reliable option.
- Choose kiln-dried, Ready to Burn hardwood logs
- Check moisture content is below 20%
- Match the species to how you'll use it
- Confirm the log size suits your appliance
- Understand loose-fill vs stacked volume before comparing prices
- Plan your storage before delivery arrives
- Order before peak winter demand
- Use natural firelighters and the top-down method
Buying firewood isn't just about finding the cheapest logs; it's about fuel that burns efficiently, stores well and suits your appliance. Whether you're looking for kiln dried Birch, Ash or Oak logs, high-performance wood briquettes, kindling or firelighters, our team is here to help you choose the right fuel for your appliance.
