Wood burning

Some wood takes up to 4 years to fully season. Depending on the weather, the way you stack the wood and how it is covered it can be ready in a little over 6 months. Use a moisture meter to ensure that the wood has less than 20% moisture. Burning wet wood can cause creosote to build up in the chimney.

Seasoned wood should be white inside with cracks at the end and dry, brittle outside bark.

The table below from the solid fuel association website shows how long common UK wood takes to season.

 

 

 

Weight per
m3 in kg

Gross heat value
 kW/kg (btu/lb)

% Moisture
when green

Seasoning time
 in summers

Hardwoods (fully air dried)

Ash

674

4.1 (6,350)

35

1

 

Beech

690

4.3 (6,700)

45

1-2

 

Birch

662

4.1 (6,350)

45

1

 

Elm

540

3.6 (5,600)

60

2-3

 

Oak

770

4.5 (7,000)

50

2-3

 

Poplar

465

2.6 (4,100)

65

1

Softwoods

Pine/Fir

410

2.6 (4,100)

60

1

Fresh felled wood weighs about one tonne per solid cubic metre but will lose up to half its weight when it becomes fully air dried, so find out for how long the wood has been seasoned before delivery or you could be getting less wood than you expect!

Softwood is easier to light but if you want to leave your fire longer between refuelling, burn hardwood – it burns longer and hotter.