Heat Values of Firewood: Hardwood and Softwood Compared

What Does Calorific Value Mean?

Calorific value is the amount of heat energy that a fuel can release when it is burned. For firewood, it is commonly measured in kilowatt-hours per tonne.

The higher the calorific value, the more heat energy is available from a given weight of dry wood. This does not always mean that one type of firewood will automatically be the best choice for every customer. The way logs are sold, stored and burned also matters.

The chart on this page compares the calorific value of different timber species by oven-dry tonne. An oven-dry tonne is timber that has had its moisture removed for measurement purposes. This gives a consistent way to compare species without moisture levels changing the result.

In real use, firewood contains some level of moisture. This is why properly dried firewood is important. Water in the logs must be heated and evaporated before the wood can burn efficiently, so wetter logs can reduce the available heat delivered into your room or stove.

Calorific Value by Firewood Species

The chart below shows that many hardwood and softwood species have broadly similar heat values when measured by oven-dry weight.

This can sometimes surprise customers who assume that all hardwood produces substantially more heat than all softwood. In practice, the difference is often more noticeable when the timber is measured by volume rather than by dry weight.

Hardwood is generally denser than softwood. A cubic metre of hardwood can therefore contain more wood fibre than the same volume of softwood. This is one reason hardwood logs can feel heavier and may suit customers looking for a denser fuel for longer, steadier fires.

Softwood is generally lighter and can take up more space for the same weight. This can make it easier to handle and useful for customers who want a fire to establish quickly.

Hardwood and Softwood Firewood Compared

Hardwood firewood comes from broadleaf trees, while softwood comes from coniferous trees. Both can be suitable for domestic heating when they are properly prepared, dry and stored correctly.

Hardwood is often chosen for regular stove use and open fires because the logs are denser. Once a fire is established, hardwood can provide a more sustained burn and may be useful for customers who use their firewood frequently during colder periods.

Softwood is often easier to light and can help a fire build more quickly. It can be practical for lighting a stove, starting an open fire or providing quicker heat for shorter periods of use.

Some customers prefer to use a combination of both. Softwood may be used when lighting the fire, followed by hardwood once the fire is established. The right approach depends on your appliance, your heating routine and the type of fire you want to maintain.

You can browse our Hardwood Firewood range if you are looking for denser logs for regular heating, or view our Softwood Firewood options for easier-lighting firewood.

Why Moisture Content Matters

Moisture content has a major effect on firewood performance. Before wet or unseasoned wood can provide useful heat, the fire must first evaporate much of the water contained within it.

This can make the fire harder to light and may reduce the heat available for your home. It can also produce more smoke and leave more moisture within the flue system than properly dried firewood.

Dry firewood is generally easier to light, easier to control and better suited to efficient burning. It is also important to keep logs dry after delivery or collection. Firewood should be stored in a covered and ventilated area, ideally raised off the ground so that air can circulate around the stack.

Customers with limited storage space may find Bagged Firewood easier to manage, while households using logs regularly may prefer a Bulk Firewood order that can be stored in a suitable shed, garage or covered outdoor area.

How Sherlogs Checks Firewood Moisture

Sherlogs processes Irish firewood and allows it to naturally air dry before it is prepared for sale. When we begin taking samples from stacks of palletised processed firewood that have been air dried for at least a year, we take a sample from one of the pallets and carry out an oven test.

The oven test provides an indication of the moisture level of the firewood within that batch. This helps us assess how the pallets are performing before they are supplied to customers.

Moisture checks are an important part of maintaining product standards. They give us confidence that the firewood being prepared for delivery or collection is meeting the quality customers expect from Sherlogs.

For customers specifically looking for lower-moisture logs, our Kiln-Dried Logs range may be the most suitable option.

Choosing the Right Firewood for Your Home

The best firewood choice depends on how you use your heating appliance and how much storage space you have available.

Hardwood may be suitable if you want denser logs and a steady fire once your stove or open fire is established. Softwood may suit you if easier lighting and quicker heat are more important. Kiln-dried logs can be a suitable choice where lower moisture content is the main priority.

It is also worth considering whether bagged or bulk firewood suits your household. Smaller bagged orders may be more convenient for occasional use, while pallet quantities can be more practical for customers who rely on firewood throughout the heating season.

Sherlogs Firewood supplies bagged and bulk firewood from Gainstown, Navan, Co. Meath. We offer delivery across Navan and selected surrounding areas, with collection also available from our yard. Please see our Delivery and Collection information before placing your order.