These are tall trees (up to 30 meters) with a large diameter (1 meter), growing in the mountainous areas (over 800 meters high). Their trunks are straight and cylindrical, showing a plain bark. They account for 1 383 000 ha. within the whole French forest.
Heartwood is not distinct from sapwood. Sawn timber is glossy cream-white. Fir is straight-grained, with thin and regular texture.
Heartwood is not distinct from sapwood. Sawn timber is white to pale pink coloured. Spruce is straight-grained with thin and regular texture.
Fir and spruce can be used without treatment in Class 1 timber (dry surrounding conditions) as well as, when treated, in Class 3 timber (humid atmosphere). Timber impregnation can be made in Class 2 (dipping) or Class 3 (vacuum pressure treatment).
Physical and mecanical properties
Fir is coarse-textured, not very fibrous, elastic and soft, with a tendency to split and warp during drying.
European spruce wood is soft, light and not very fibrous. European spruce has a good stiffness/weight ratio and its long fibres make it very resistant to bending, except when weakened by the presence of knots.
|Average density||450 kg/mᶟ|
|Total average volumetric shrinkage||11.4 % – 12.7 %|
|Brinell hardness perpendicular to the fibres||14 N/mm²|
|Modulus of rupture under bending||100 MPa|
|Breaking stress under axial compression||44 MPa|
|Modulus of longitudinal elasticity under bending||12 700 MPa|
Conditions of implementation
Fir and spruce are ideal for frameworks, included for glued laminated timber, as well as for wooden structures (for instance : footbridge). Sawn timber is also currently used for joinery, flooring, skirting boards and moulding.