Running out of logs on a cold night is no fun, but buying far more than you can store isn’t ideal either. Working out how much firewood you need is simpler than it sounds: once you know how much a bag holds and how often you light the fire, the rest is easy maths. Here’s our rule of thumb, how we worked it out and when to order so you never run short.
The quick answer:
- One of our bulk bags (85 x 85 x 85cm, about 0.6m³ of loose logs) gives roughly 90 hours of burning on a typical 5kW wood burner.
- That’s about 3–4 weeks if you light the stove most evenings, 7–8 weeks if you only have fires at the weekend, and around a week if your stove is your main heat source.
- From mid-October to the end of March, a home that burns most evenings needs 6–7 bulk bags.
- Standard delivery is currently within two weeks, so reorder when you have about two weeks of logs left.
These are estimates. Your stove, your house and how you burn will all make a difference, so treat them as a starting point and adjust after your first bag.
Jump to Section:
- How Long Does a Bulk Bag of Logs Last?
- How Many Bulk Bags Do I Need for Winter?
- What Does an 85 x 85 x 85cm Bulk Bag Hold?
- Bulk Bags vs Barrow Bags
- When Should I Order Logs for Winter?
- How to Make Your Logs Last Longer
- Kiln-Dried Logs Delivered by Westdale Logs
- How Many Logs Do I Need? FAQs
How Long Does a Bulk Bag of Logs Last?
A bulk bag of kiln-dried hardwood logs lasts for roughly 90 hours of burning on a typical 5kW wood-burning stove. How many weeks that works out to depends on how often you light the fire:
| How you use your stove | Hours a week (approx.) | One bulk bag lasts |
|---|---|---|
| Weekend fires – a few hours on Friday, Saturday and Sunday evenings | 12 | 7–8 weeks |
| Most evenings – around 4 hours a night, 6 nights a week | 24 | 3–4 weeks |
| Evenings and weekends – most evenings plus all day at the weekend | 40 | About 2 weeks |
| Main heat source – lit for 10–12 hours every day | 75 | About 1 week |
How We Worked It Out
We’d rather show our working than give you a number you can’t check:
- The bag: our bulk bags measure 85 x 85 x 85cm, which holds about 0.61m³ (614 litres) of loose logs.
- The energy: according to Forest Research, logs dried to 20% moisture contain about 4.1kWh of energy per kilogram, or 1,400–2,000kWh per stacked cubic metre. Allowing for the air gaps in a loose bag, that puts a bulk bag at roughly 600kWh.
- The stove: a modern wood burner turns around 75% of that energy into heat for your room, which leaves about 450kWh of useful heat per bag.
- The result: a 5kW stove running at its rated output uses about 5kWh of heat an hour, so one bag gives roughly 90 hours of burning. That’s around 1.5–2kg of logs an hour.
What Makes a Bag Go Faster or Slower?
- Stove size – a 4kW stove run at full output would stretch a bag to around 115 hours, while an 8kW stove would get through it in about 60.
- How hard you run it – a stove turned up high burns through logs much faster than one ticking over at a steady, moderate heat.
- Stove or open fire – open fires send far more heat up the chimney than stoves, so expect a bag to go considerably faster.
- Your house and the weather – a draughty room in a January cold snap needs more fuel than a well-insulated one in October.
- How dry your logs are – wet wood wastes energy boiling off water. Our logs are Ready to Burn certified at typically around 18% moisture. Read more in Are Kiln-Dried Logs Better Than Seasoned Logs?
- The wood itself – dense hardwoods burn more slowly than lighter woods. Our hardwood bulk bags are mostly ash, alongside beech, cherry and birch, and our oak bulk bags are a good choice if you like long, slow burns.
How Many Bulk Bags Do I Need for Winter?
Most homes that light a wood burner most evenings need 6–7 bulk bags to get from mid-October to the end of March. Here’s how that changes with your burning habits, based on a 24-week winter:
| How you use your stove | Bulk bags for the whole winter | Roughly one bag every |
|---|---|---|
| Weekend fires | 3–4 | 2 months |
| Most evenings | 6–7 | Month |
| Evenings and weekends | 10–12 | 2 weeks |
| Main heat source | Around 20 | Week |
You don’t need to buy a whole winter’s worth at once. Ordering a bag or two at a time and topping up through the season keeps storage manageable and means your logs stay in top condition. If you have the space, taking two or three bags before the first cold snap gives you a comfortable buffer.
What Does an 85 x 85 x 85cm Bulk Bag Hold?
An 85 x 85 x 85cm bulk bag holds about 0.61m³ (614 litres) of loose logs, which is roughly 0.37m³ once stacked neatly. Loose logs tumble into a bag with plenty of air gaps between them, so the same logs take up less room when you stack them. As a rule, a loose volume is about 1.6–1.7 times its stacked volume.
That matters in two ways:
- Comparing suppliers – bulk bag sizes vary, and some suppliers quote stacked volumes while others quote loose. Always check the bag dimensions and compare price alongside size. We list ours on every product page, and you can see how we compare on our Why Choose Us page.
- Planning your storage – a log store about 1m wide, 1m high and 40cm deep holds roughly one bulk bag once stacked.
Our hardwood bulk bags come in a choice of two log lengths, 8–10" or 10–12", so measure your stove’s firebox before you order. Logs that fit comfortably burn more evenly.
Bulk Bags vs Barrow Bags: Which Should You Choose?
Bulk bags are the most cost-effective way to buy logs, while barrow bags are smaller and narrower, making them ideal for homes with tight access or limited storage.
| Bulk bag | Barrow bag | |
|---|---|---|
| Bag size | 85 x 85 x 85cm | 46 x 46 x 87cm |
| Volume | About 614 litres | 185 litres |
| Burn time on a 5kW stove | Around 90 hours | Around 25–30 hours |
| Best for | Regular burners, homes with a driveway or easy access | Terraced houses, narrow passageways, small log stores, topping up |
If you burn most evenings and have the space, a bulk bag of hardwood logs gives you the most firewood for your money. If you’re in a terraced house or can’t get a large bag through to your log store, our barrow bags are easy to move and stack, and our Double Barrow Bag deal gets you two at a discounted price.
When Should I Order Logs for Winter?
Order your next bag when you have about two weeks of logs left, and stock up before the first proper cold snap. Our standard delivery lead time is currently within two weeks (you can always see the latest lead time in the banner at the top of our website), although it can stretch during the busiest weeks of winter.
Here’s when to reorder, depending on how you burn:
| How you use your stove | When to reorder |
|---|---|
| Weekend fires | When about a quarter of the bag is left |
| Most evenings | When the bag is about half empty |
| Evenings and weekends | As soon as you open a new bag |
| Main heat source | Always keep a spare full bag, and reorder as soon as you open a new one |
Run out unexpectedly? Our next-day delivery bulk bag is there for exactly that. Order between Sunday and Thursday and your logs arrive the next day; orders placed on a Friday or Saturday arrive the next working day.
How to Make Your Logs Last Longer
- Burn dry wood – logs below 20% moisture put their energy into heating your room rather than boiling off water.
- Keep your logs dry – store them off the ground, under cover and with plenty of airflow. We deliver with a complimentary rain cover on rainy days, and our bulk bags are vented to help prevent damp.
- Burn steadily – follow your stove manufacturer’s instructions and avoid shutting the air down so far that the fire smoulders. A smouldering fire wastes fuel and creates more smoke.
- Load little and often – adding a log or two at a time keeps the fire burning efficiently, while overfilling the firebox burns through fuel quickly.
- Get the right log length – logs that fit your firebox properly burn more evenly.
- Spread the heat – a stove fan helps move warm air around the room, so you may not need to run the stove as hard.
- Keep your chimney swept – a clean flue helps your stove draw properly and burn efficiently.
Kiln-Dried Logs Delivered Across Sheffield, Chesterfield & the Peak District
At Westdale Logs, all our kiln-dried firewood is Ready to Burn certified with a moisture content below 20% (typically around 18%) and is dried in our own solar-powered kiln in the Hope Valley.
We offer free local delivery to Sheffield, Chesterfield and the Hope Valley and Peak District, with next-day delivery available Monday to Friday. Need kindling too? Our Winter Warmer Bundle includes a bulk bag of hardwood logs plus two bags of kindling.
Browse our bulk bags and barrow bags.
How Many Logs Do I Need? FAQs
How long does a bulk bag of logs last?
A bulk bag of kiln-dried hardwood logs lasts roughly 90 hours of burning on a typical 5kW stove. That’s about 3–4 weeks if you burn most evenings, 7–8 weeks if you only have weekend fires, and around a week if your stove is your main heat source.
How many bulk bags of logs do I need for winter?
Most homes that use a wood burner most evenings need 6–7 bulk bags between mid-October and the end of March. Weekend-only users need around 3–4, while homes that rely on a stove as their main heat source can need around 20.
How much wood does a log burner use per hour?
A typical 5kW wood burner uses around 1.5–2kg of dry logs an hour when running at its rated output. Larger stoves, open fires and wetter logs all use more.
What’s the difference between a bulk bag and a barrow bag?
Our bulk bags measure 85 x 85 x 85cm and hold about 614 litres of loose logs, while our barrow bags measure 46 x 46 x 87cm and hold 185 litres. Bulk bags offer the best value, while barrow bags are narrower and easier to move, which makes them ideal for terraced houses and homes with tight access.
How much space do I need to store a bulk bag of logs?
Stacked neatly, a bulk bag of logs takes up about 0.37m³, so a log store roughly 1m wide, 1m high and 40cm deep will hold one bag. Keep your logs off the ground, under cover and with good airflow so they stay dry.
Do kiln-dried logs last longer than seasoned logs?
Kiln-dried logs give you more heat per log because less of their energy is spent evaporating water. That means you need fewer logs to heat the same room. Find out more in our guide, Are Kiln-Dried Logs Better Than Seasoned Logs?
Can I get logs delivered the next day?
Yes, we offer next-day delivery on our kiln-dried hardwood bulk bags from Monday to Friday. Order between Sunday and Thursday for delivery the next day. Orders placed on a Friday or Saturday are delivered the next working day. Order next-day logs.
Written by the Westdale Logs team. With a background in arboriculture, we select, split and kiln-dry our own hardwood logs in the Hope Valley and deliver them across Sheffield, Chesterfield and the Peak District.