What are the special features of pine as a material?
Short symbol DIN EN 13556: PNSY
Botanical name Pinus sylvestris; Family Pinaceae
Distribution: Europe, east to Siberia; Asia Minor
Trade names: pine, common pine (DE); Scots pine (CH); pin commun, pin sylvestre (FR); pino silvestre (ES, IT); Baltic redwood, pine, scots pine (GB); grove den (NL)
The domestic pine, Tree of the Year 2007, is with 24 % forest share (approx. 2.5 million ha) and 21 % of the timber stock after the spruce the most important forest and commercial tree species in Germany. The moderately heavy wood, together with that of the black pine (P. nigra) and a few other pines from North America (P. resinosa = red pine) and East Asia (P. densiflora = Japanese red pine), forms a firmly defined group, which lies between the lighter soft pines and the heavier hard pines (both important pine assortments in North America) in terms of weight and properties.
The sapwood is white and yellowing in the light, in younger trees often occupying the greater part of the trunk volume; the heartwood is clearly separated, yellowish to reddish brown, darkening strongly in the light. The regular alternation between light early wood and darker late wood results in distinct grain on tangential surfaces and narrow stripes on radial surfaces. Resin channels are good on smooth cross-sections with a magnifying glass, on longitudinal surfaces just visible. Fresh wood has a strong resinous smell.
Straight grained, sometimes very resin-rich softwood with a clear core colouring, clearly structured by the change from light early wood to dark late wood bands.
Compressed wood (redwood); resin accumulation (red hardness, pine wood and resin galls) caused by damage during growth, e.g. after long-term resinification
Pine wood, after appropriate removal of any resinous areas, should be treated well with any means and by any method, covering or glazing. It is similarly advantageous in this respect as, for example, spruce, larch and Douglas fir. After prolonged storage in water, bacterial attack can cause uneven absorption of the agents in the sapwood, resulting in staining.
The processing of the wood requires little effort and results in particularly smooth planed surfaces. When sawing, planing, and especially when sanding resin-rich qualities (red hard wood), the tools can resinify quickly and cause corresponding processing defects. The wood is also easy to cut and peel. Corner joints nails and screws as well as glued joints hold well.
The average shrinkage values result in a usually still good staying power. The technical drying process is fast and without specific difficulties; however, too sharp drying programs can lead to fine cracking, especially in the permeable sapwood.
Areas of application
Pine wood is offered as round timber, sawn timber and veneer, more rarely in the form of glued construction elements (solid structural timber, glued laminated timber, glued scantlings). In interior construction, pine is versatile and can be used for skeleton constructions, load-bearing walls and ceilings, floors, staircase, wall and ceiling panelling, built-in furniture, etc., and in exterior construction for façade cladding, balconies, windows and doors, fences and gates. In addition, pine is an important bulk wood for many wood-based materials and for the pulp and paper industry.
Pine – Technical Properties
Weight fresh750-850 kg/m³
Bulk density air-dry (12-15% u)0.51-0.55 g/cm³
Compressive strength u12-1545-55 N/mm²
Flexural strength u12-1579-100 N/mm²
Modulus of elasticity (bending) u12-1510 800-13 000 N/mm²
Hardness (JANKA) ⊥, converted2,2-5,1 kN
Hardness (BRINELL) ⊥ to fiber u12-1514-23 N/mm²
Differential shrinkage (radial)0.15-0.19 %
Differential shrinkage (tangential)0,25-0,36 %
Natural durability (DIN-EN 350-2)3-4