Perfectly known to cruciverbists, the stere is an ancient unit of measurement (st) of the volume of wood, whose origin comes from the Greek "stereos" meaning solid.
Although its use should have ceased at the beginning of 1978 because it was officially replaced by the cubic meter, this unit of the stere is still frequently used in the timber trade, whether for industrial use, carpentry, or more commonly, heating.
If in theory the stere is the equivalent of 1 cubic meter, that is to say the volume defined by 1 frame of 1 meter in length by 1 meter in width and 1 meter in height, in practice, stacking logs on top of each other will give a total volume of wood less than 1 cubic meter.
This is simply explained by the fact that there is a lost space between each log, each of them being in the cylindrical form of round wood or logs, and not in the form of flat planks which would have thus made it possible to actually totally occupy this volume of 1 cubic meter. It therefore became urgent to be able to quantify this lost space because on an industrial scale, the shortfall can quickly take on significant proportions.
In order to standardize this relationship between the apparent volume of 1 cubic meter and the actual volume of wood contained in the frame, ADEME, the French agency responsible for the NF certification of firewood, recommends cutting the wood into sections according to well-defined lengths, between 20 centimeters and 1 meter.
According to the calculations of this organization, this standardization would thus make it possible to evaluate fairly precisely the real volume of wood contained in a frame of 1 cubic meter, knowing that when the wood is cut into sections it is easier to fill the holes.
For example, 1 stere of wood cut into logs of 20 centimeters is equivalent to a real volume of 0.57 cubic meters, logs of 33 centimeters give 0.70 cubic meters, the simplest formula to remember being "1 stere with logs 1 meter long will give 1 real volume of 1 cubic meter".
In all cases, for firewood, and always with this concern for transparency and thus avoiding suspicion between buyers and sellers, the NF standard recommends affixing visible labeling clearly indicating this ratio between the apparent volume of the frame and the volume real wood, a ratio which will therefore be conditioned, as we have seen, by the length of the logs.
Before placing an order for your stere of firewood, you should check its humidity level. Humidity class H1 corresponds to a humidity level below 20%, therefore immediately ready for use. Class H2, on the other hand, corresponds to a humidity level above 20%. Beyond 35% humidity, your cubic meter of wood will require a storage period before it gives its maximum heat output by burning in your fireplace or in your wood stove.
