About wood
That we don't plop treated or wet wood into the wood supply of our Jackie outdoor stove is beyond dispute. But which wood burns best? How big should the pieces be? And where do I find my wood? Here are all the answers!
Which wood
Firing with wood requires some preparation, as this material does not 'grow on trees ready-made'. Where you get this wood affects your emissions. A list of responsible suppliers is being built on jackie.eco but this does not currently cover all locations. So what are the options:
You get wood from the nearest DIY store:
This wood was often delivered by fairly large companies in plastic nets or bags. Pity about that packaging. The forests where these big companies mine are Eastern European or Russian and may bear the FSC or PEFC label, but the transport is a downside. And you might question whether forest management there is really that ethical
Local firewood merchant:
A good option in many cases. Wood comes from local forests. Non-native tree species or trees felled to give a chance for other trees to grow. Feel free to ask for FSC- or PEFC-labelled wood! The packaging itself is made of wood, for larger quantities. Ideal therefore.
Local felling or pruning company
Jackie has the advantage that prunings are more than enough to start a bright fire. There is little demand for this these days, and most prunings end up being shredded. Let's change that.
Tree species
Oak, beech, hornbeam, ash, willow, poplar, spruce, birch. Each with its slight advantages or disadvantages, but always enjoyed by Jackie. Avoid pine.
Wood quantity
Per firing, you consume 5kg for a few hours to double for a whole evening. This is half to a full bag as available from many suppliers.
It may be more convenient to stockpile a larger quantity at once and store it in the garden: a real cubic metre (stacked, sawn and split wood): 1.0 m3 (about 700 kg), a dump cubic metre (split wood deposited in 1-m3 bins): 0.6 m3 (about 400 kg) or a 'stere' (stacked one-metre pieces of un-split wood): 1.2 m3 (about 900 kg).
Kindling
By definition, wood that burns easily, partly because it is quite thin. This is often spruce. Also available from the above suppliers. Store in a dry place.
Dry, but not too dry
Each type of wood is best dried for two years before it can be used. The moisture percentage should be between 12 and 18% for clean burning. So check with your supplier, because you can usually get both dried and un-dried wood.
How do you recognise dry wood? After splitting, measure with a moisture meter in the core of the wood. So this should be between 12 and 18 per cent. Haven't you measured? Wet wood will produce smoke and thus fine dust once you use it in your Jackie outdoor stove.
Can wood be too dry? Yes! Wood with a moisture percentage below 10% can cause too much burning, burning too much material at once and not enough oxygen being supplied. A minimal moisture level keeps the fire under control. Here you can read more about wood that is too dry.
Once you have the wood, you also need to be able to store it dry: this is best done outside in piles with a cover plate on top and easily accessible from sun and wind. Be careful if you store wood in an unheated garage, garden shed, or barn: the wood will become more damp again. Indoors, your wood can become too dry again.
Preparing wood for Jackie
Jackie prefers wood of about 3 by 3 cm. That means: split it! Standard logs are best split into 4 or 6 pieces. This activity is definitely part of the outdoor life you aspire to with an outdoor stove like Jackie. But if you live in the city, it is best to do this during the day, to avoid noise pollution for the neighbours while sitting around the fire.
The length of the pieces of wood is less of an issue, as the wood supply must always remain open anyway. However, it is more difficult to split 50cm pieces than 30cm pieces.