Wood Species Guide for Timber Construction

Reference data on the density, strength, hardness and natural durability of the wood species and engineered wood products most commonly used in facades, cladding, structural timber and interior surfaces. Compiled for architects, builders and specifiers.

Softwoods

"Softwood" means botanically coniferous wood, not necessarily physically soft — larch, for example, is stronger than many hardwoods.

Species	Latin name	Density (kg/m³, 12%)	Janka hardness (N)	Bending strength MOR (MPa)	Durability (EN 350)	Typical use
Norway spruce	Picea abies	405	1,680	63.0	4 – slightly durable	Structures, glulam, interior lining, furniture
Scots pine	Pinus sylvestris	550	2,420	83.3	3–4 – moderately to slightly durable	Structures, floors, windows, treated exterior wood
European larch	Larix decidua	575	3,290	90.0	3–4 – moderately durable	Facades, decking, posts, boatbuilding
Douglas fir	Pseudotsuga menziesii	510	2,760	86.2	3–4 – moderately durable	Load-bearing structures, beams, facades, plywood
Silver fir	Abies alba	415	1,420	66.1	4–5 – slightly or not durable	Structures, plywood, interior finishing, pulp
Western red cedar	Thuja plicata	370	1,560	51.7	2 – durable	Facades, saunas, exterior cladding, shingles

EN 350 durability class: 1 = very durable, 5 = not durable. Applies mainly to heartwood; sapwood is generally not durable. Density and mechanical values can vary ±10% with growth conditions and moisture. For structural design, use the strength class of graded timber (e.g. C18 or C24).

Hardwoods

Species	Latin name	Density (kg/m³, 12%)	Janka hardness (N)	Bending strength MOR (MPa)	Durability (EN 350)	Typical use
English oak	Quercus robur	675	4,980	97.1	2–4	Floors, furniture, stairs, exterior details, barrels
European ash	Fraxinus excelsior	680	6,580	103.6	5	Floors, furniture, tool handles, sports equipment
European beech	Fagus sylvatica	710	6,460	110.1	5	Furniture, stairs, floors, bent components
Silver birch	Betula pendula	640	5,360	114.3	5	Plywood, furniture, floors, turned components
Black alder	Alnus glutinosa	535	2,890	91.4	5 (durable permanently submerged)	Saunas, interior lining, furniture, plywood
European aspen	Populus tremula	450	1,650	62.0	5	Sauna benches, interior lining, matches, packaging

Engineered wood products

Material	Typical density (kg/m³)	Strength / stiffness	Moisture resistance	Main use
Spruce plywood	≈460	Medium; stronger along face grain	EN 314-2 class 3 glue available	Walls, roofs, floors, packaging
Birch plywood	≈680	Very strong and stiff, good screw hold	Exterior glue available; protect edges	Furniture, transport, floors, formwork
OSB/3	600–680	Structural board; strength depends on direction	Usable in humid conditions, not waterproof	Walls, roofs, subfloors
MDF	650–800	Uniform, well machinable; medium strength	Standard for dry areas; MDF.H for humid	Furniture, doors, painted and milled parts
LVL	≈510	Very strong in main direction; LVL 32–48	Usually in protected structures	Beams, posts, lintels, floor elements
CLT	≈490	Load-bearing mass timber panel	Service classes 1–2; needs weather protection	Walls, floors, roofs, stairs
Glulam	430–500	GL24: bending 24 MPa, MOE ≈11.5 GPa	Interior and protected exterior	Beams, posts, arches, long spans

Plywood class 3 glue = moisture-resistant bond, not that an uncoated panel can stay outdoors indefinitely. CLT, LVL and glulam are load-bearing structural materials — use the manufacturer's declaration of performance for design.

Timber used in facades, cladding and public buildings often needs to meet reaction-to-fire requirements. Learn how SPFR100 achieves EuroClass B-s1,d0 on timber →