Wood burning update from Julian Evans (FTN June 2006).
In last autumn’s issue of Forestry and Timber News I described how we bought and installed
a modern wood-burning stove. To join in the theme of this issue, here I want to tell you how
we’ve got on and, importantly, what we have learned after the first winter’s burning, and after
a pretty cold winter at that!
Mastering the stove
The first point is painfully obvious, but unless it’s grasped success with a stove will be
indifferent. Your aim is to get the stove itself hot, that is the basic steel box inside which your
burn the wood. It is the heat of the stove that then radiates to warm the room. By contrast in
an open fire it is heat directly from the flames and embers that warms you. This elementary
point only sank in after a few lightings and it altered the approach to using the stove. Let me
explain.
Instead of lighting a fire because the room is feeling cold or just before guests arrive to give
that welcome of flames playing in the hearth, you light the fire about two hours before you
want the warmth. The steel casing of the stove, 5-7 mm thick, takes time to warm up so you
need to anticipate when you want the room to be warm and snug. Once the stove is really
hot, the bricks above the fireplace and the fireplace surround can get pretty warm too, but
hours of comfort are yours as stove, surround and fireplace radiate their warmth. You can
still have that flames and see them through the glass door.
First then, we learned to light the stove well in advance of wanting the warmth. Secondly, this
led to a fire burning strategy of lighting and burning quite fast for the first hour or so to raise
the temperature, and then slowing things down to maintain the warmth. Thirdly, when all is
hot the embers will ‘stay in’ for hours and can be ‘revived’ to burn new wood with very little
difficulty.
The lack of wood ash is as we were told. Even with daily use, the efficient stove only required
removal of ash about once every three weeks. The advice, too, of burning the logs on a floor
of ash with fresh air coming from above, proved absolutely right: wood burns best this way,
not with air drawn from beneath which is the ideal for coal.
For an evening’s warmth we find we burn a basketful of dry logs, say 15 or 20, and weighing
around 10-15 kg. We have found too, that the one stove, rated at 7 kilowatt hours, is enough
to supplement the central heating for both the living and dining rooms so the latter doesn’t
need to be turned up or kept on for longer on a cold winter’s evening. The stove is saving
some heating oil and doing a bit for the planet.
Lessons about the firewood itself
We already knew the absolute essential of having thoroughly dry timber. Our supply of such
well-seasoned logs was insufficient and so we turned to burning ash, with its fabled
reputation, that had been cut and stacked in cords about eight months earlier but not kept
under cover. It burned quite well, but sap boiling off from the ends of the logs when burning
in the stove showed that they still had too much moisture for top efficiency. Interestingly, this
wasn’t the case for sycamore that had similarly been cut eight months before. Not only did
the logs feel light, but they burned well. So, although ash burns straight from the tree
because of its low natural moisture content, it may season more slowly than sycamore with
the latter becoming the better option in time. This is just an observation.
One final lesson is to split all logs before storing. Even quite small ones should not be left in
the round since the bark acts as a good barrier to drying. So it’s the old, old lesson. Do
everything to ensure that your firewood is as dry as possible: season for at least one year,
split all logs, and keep them under cover.
Happy wood burning!