Raw materials
Proper lumber – what does that mean?
Below we have listed some main criteria that must be met before it can be said that the lumber is suitable for a cabin / residential purpose.
Proper lumber – what does that mean?
Below we have listed some main criteria that must be met before it can be said that the lumber is suitable for a cabin / residential purpose.
These are timbers whose fibers have grown to the left throughout the life of the tree. This is a phenomenon that no one quite knows the cause of. Normally, the fibers will grow to the left in “youth”, then be relatively straight-grown for many years, and then right-twisted. (on the south side of the Equator they grow opposite, so the sun must have a meaning) Sticks that have a straight or right fiber slope are therefore not dangerous to use as a laft. Left-handed logs become unstable, and will give leaky lath. Be especially wary of long logs that are left-handed. Tinnoset Sag tries to avoid and deliver left-handed logs, but should there be a miss, it is important that the loggers are aware of the phenomenon and do not use the log in the building.
Slow-growing timber is stronger. This applies to pine and our other conifers. The optimal annual ring width of conifers is about 1 mm. If it is much slower, we call it hunger, and it is actually somewhat weaker again. The strength of deciduous trees is normally unaffected by how fast they have grown, while the ring-pore deciduous trees, oak, ash and elm actually become stiffer if they grow fast. We use pine as lumber, and most often spruce for hills. We only buy slow-growing timber. This timber is stronger, is more durable, is more stable and has less rot and black twig.
There are many words for the reddish-brown core of the pine. The most commonly used are ores, heartwood or al. Furua’s heartwood stands out in that it is filled with resinous substances that make it naturally resistant to insects, rot and fungi. Ore timber is also more stable than timber with little ore. Some growing places give the timber more ore than others, but it is generally the largest timber that has the highest proportion of ore. We are careful to use malment timber. This is especially important in the bottom logs, which are most exposed to moisture.
Artificially dried timber is timber that holds a maximum of 18% moisture content. When the timber is artificially dried, we also avoid blue wood. Blue wood is a fungus that attacks the cell wall in the log, and gives it poorer resistance to moisture.
Read more about our timber.