Pseudotsuga menziesii
Douglas Fir
Not a fir, and the stiffest softwood KORENA lists. Bold orange ring figure, structural strength, and a splinter you do not want to ignore.
- Coltivato fuori dall’Europa e importato tramite depositi europei.
- Gruppo botanico. Le conifere hanno foglie aghiformi, le latifoglie hanno foglie larghe.
- La famiglia botanica a cui appartiene la specie.
Avvisami quando arrivaSpecie di riferimento. Al momento non ci sono pezzi disponibili.
È adatto al tuo progetto?
Ideale per
- Structural beams and exposed framing
- Tabletops
- Flooring
- Exterior joinery
- Shelving with long spans
Nessun pezzo di Douglas Fir nel lancio attuale
Specie simili disponibili
Al momento non è disponibile Douglas Fir. Queste specie sono adatte agli stessi progetti e hanno pezzi disponibili.
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Ti inviamo un’email quando arrivano nuove tavole di Douglas Fir su KORENA. Ogni pezzo è unico, quindi conviene saperlo in anticipo.
Aspetto del legno
Che aspetto ha
Warm reddish tan to light brown heartwood with a distinctly orange cast, against pale sapwood. The ring figure is bold and high contrast because the latewood bands are dense and dark, giving flatsawn faces a strong flame pattern. It is one of the stiffest softwoods available, which is why it dominates structural engineered timber.
- Reddish tan to light brown with a warm orange cast
- Bold high contrast growth ring figure
- Pale narrow sapwood, deepens with light exposure
- Straight grain with bold, high-contrast growth rings from dense dark latewood. Reddish tan to light brown with a warm orange cast against pale sapwood.
Lavorazione
Come si lavora
Machines well but has a moderate blunting effect on cutters, noticeably more than spruce or pine. It accepts stains, glues and finishes well. The dense latewood bands are the machining challenge: they are much harder than the earlywood between them and can tear out where grain rises, leaving a ridged surface. Sharp tooling and light finishing cuts matter, and a helical head is a real advantage.
Finitura
Takes oil and clear finishes well and the colour deepens attractively toward a richer red brown. Like all species with strong density contrast between earlywood and latewood, it blotches under pigment stain, so a conditioner or dye is the safer route. Its natural colour is warm enough that most makers leave it clear.
Essiccazione
Dries reasonably well but is prone to surface checking in thick sections if pushed, and European grown fast ring stock is more troublesome than slow grown material. Volumetric shrinkage at around 11.6 percent is the lowest in this group, which combined with a favourable tangential to radial ratio makes properly dried Douglas Fir one of the more stable softwoods in service.
Quanto si muoverà?
Il legno si gonfia e si ritira in larghezza al variare dell’umidità dell’aria. Stima il movimento stagionale di un piano in Douglas Fir prima di progettare i fissaggi.
Movimento stagionale previsto
circa 8,3 mm
Fissa il piano con nottolini o staffe asolate, non con colla o viti serrate.
Modello di ritiro lineare: larghezza × (ritiro ÷ 28 % di saturazione delle fibre) × variazione stagionale dell’umidità. Usa un ritiro tangenziale del 7,3 % per Douglas Fir. È una stima di progetto, non una garanzia.
Quanto costa
Sicurezza e provenienza
- Coltivato fuori dall’Europa e importato tramite depositi europei.
- Stato nella Lista rossa IUCN: la valutazione globale dello stato di conservazione di questa specie.
Reported to cause skin irritation, nausea, giddiness and runny nose, along with an increased likelihood of splinters becoming infected. That last point is worth taking seriously: Douglas Fir splinters are notorious for going septic. Gloves when handling rough stock and proper extraction during machining are advisable.
Leggi la guida completaNote approfondite su marezzatura, variazione del colore, lavorazione e stabilità.
What Douglas Fir actually is#
Pseudotsuga menziesii is not a fir. It sits in its own genus, separate from the true firs of Abies, and the name is a historical accident that never got corrected. The distinction is not pedantry. Silver Fir is the softest wood in this catalogue at 1,420 N Janka; Douglas Fir is nearly twice as hard at 2,760 N, considerably stiffer, more durable, and much harder on cutting edges. Expecting one to behave like the other leads to bad decisions.
It is native to western North America and has been planted across Europe since the nineteenth century. That matters when buying, because European plantation stock and North American old growth are the same species performing quite differently.
Reading a Douglas Fir slab#
The colour is the immediate draw: a warm reddish tan with an orange cast that deepens under light toward a richer red brown. Against the pale narrow sapwood the contrast is clean.
The ring figure is the real signature. Douglas Fir lays down dense dark latewood bands against much softer earlywood, and on a flatsawn face that produces a bold flame pattern with high contrast, closer to a ring-porous hardwood than to the quiet figure of spruce.
That same contrast is what you must read for quality. Ring spacing separates slow grown material, with a high proportion of dense latewood, from fast grown European plantation stock with wide soft earlywood bands. The slow grown board is stronger, more durable and more attractive. The fast grown one is neither wrong nor a bargain, it is simply a different material, and for structural or exterior work the difference is not cosmetic.
Domande degli acquirenti
Domande degli acquirenti
Is Douglas Fir actually a fir?
No. Pseudotsuga menziesii is its own genus, distinct from the true firs in Abies such as Silver Fir. The name is a historical misnomer that stuck. The practical consequence is that it behaves nothing like Silver Fir: it is far stiffer, harder, more durable and considerably more difficult on cutting edges.
How stiff is it compared to other softwoods?
Its elastic modulus is 12.17 GPa, the highest of any softwood KORENA lists and above European Larch at 11.80 GPa. Stiffness is why it dominates structural glulam and why it is the right choice for a long shelf or an unsupported span where deflection matters more than hardness.
Can I use it outdoors?
It is rated moderately durable regarding decay but is susceptible to insect attack, so it sits below European Larch for exterior work. It performs well in protected exterior joinery such as windows and doors under a maintained finish. For unprotected decking or ground contact, larch is the better choice from this group.
Why do Douglas Fir splinters get infected so often?
Proprietà meccaniche
Dati tecnici
Valori di riferimento pubblicati. Quando le fonti non concordano, viene mostrato l’intervallo e il valore tipico è usato per le scale sopra.
| Densità (kg/m³)Massa per metro cubo con circa il 12 % di umidità. In genere, un legno più pesante è anche più duro e resistente. | 510 kg/m³ |
|---|---|
| Durezza Janka (N)Forza necessaria per spingere una sfera d’acciaio fino a metà nel legno. È la misura standard della resistenza alle ammaccature. | 2,760 N |
| MOR: modulo di rottura (MPa)Resistenza alla flessione: il carico al quale una trave si rompe. | 86 MPa |
| MOE: modulo elastico (GPa)Rigidità alla flessione: quanto si incurva una mensola o un piano sotto carico. | 12.2 GPa |
| Ritiro radialeRitiro trasversale agli anelli di crescita, dal legno verde a quello anidro. È il movimento delle tavole a taglio radiale. | 4.5 % |
| Ritiro tangenzialeRitiro lungo gli anelli di crescita. È il movimento delle tavole a taglio tangenziale e della maggior parte delle tavole KORENA. |
