Wood species are the different types of wood, classified according to the tree they come from. The main division is between softwood (from conifers) and hardwood (from broadleaf trees). Each species has its own properties in terms of strength, weight, durability, appearance and workability, and is therefore suited to different applications.
Softwood and hardwood
- Softwood — usually lighter and faster grown, easy to work and affordable. Examples: spruce, pine, larch and Douglas fir. Widely used for structural timber, framing and roof boarding
- Hardwood — often heavier, harder and more durable, but more expensive. Examples: oak, beech, meranti and tropical species. Used for window frames, furniture, floors and where high durability is needed
Durability classes
The natural resistance of wood to fungi is expressed in durability classes 1 (very durable) to 5 (not durable), according to the standard NEN-EN 350. For outdoor use without preservative treatment, choose a species in a low (favourable) class.
Choosing in practice
- Structural — pay attention to strength class (for example C24 for softwood)
- Outdoor — choose a durable species or preservative-treated wood, and look for an FSC or PEFC mark for responsible sourcing
- Visible work — colour, figure and grain determine the choice
- Moisture movement — wood moves (shrinks and swells) with the humidity; take this into account with floors and window frames
Related terms
- Wood
- Softwood
- Hardwood
- Durability class
- FSC
- Movement of wood
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