Log In for TreeMendous Advice

Here is some useful advice from The Forestry Commission for choosing the right type of wood for your wood burner...(and some interesting facts)

​Choosing logs
When choosing wood for burning there are two significant factors which have an effect on the
calorific value (CV) or the amount of available heat per unit (volume) of fuel:
1. Moisture content
2. Wood density

1. Moisture content
The moisture content of wood has by far the greatest effect on CV. Any water in the timber has to
boil away before the wood will burn, and this will reduce the net energy released as useful heat
(as opposed to steam up the chimney). If you can get them to light at all, logs that aren’t dry will
result in a fire that smoulders and creates lots of tars and smoke. These tars can be corrosive,
potentially damaging the lining of the flue and increasing the danger of a chimney fire. Wet logs
will tend to blacken glass in stoves even if the stove is designed to keep the glass clean. Well
seasoned logs can have approximately twice the CV of green logs.
You should always take care to burn only dried (seasoned) wood, either by buying it dry, or by
buying green logs and drying them yourself. Radial cracks and bark that comes off easily
suggests well-seasoned wood.

2. Wood density
When buying logs, it is common for the seller to let you know whether they are from hardwood or
softwood tree species (or mixed). The general difference is that hardwoods (deciduous,
broadleaved tree species) tend to be denser than softwoods (evergreen, coniferous species). This
means that a tonne of hardwood logs will occupy a smaller space than a tonne of softwood logs.
Denser wood tends to burn for a longer period of time meaning fewer ‘top ups’ are required to
keep a log stove burning for a given length of time. If you buy wood by volume you will receive
more kilowatt hours (kWh) of heat from a cubic metre (m3 ) of hardwood than softwood (at the same moisture content). 

For more advice and useful government info on this subject download the pdf file below...

---

click here to download the file