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By Deepak Kumar · Founder, Vriksai

Europe

European Oak

Quercus robur

Also known as English oak, French oak, white oak (European) · Botanical Quercus robur, Quercus petraea

Last updated: 15 July 2026Reviewed by: Vriksai editorial team — timber trade professionalsEditorial policy

Revision history

17 July 2026 — Data re-verified in site-wide audit (formulas, sources, durability classes)
15 July 2026 — Working properties and comparable-species data cross-checked against listed sources

🪵Hardwood🌧Outdoor💧Moisture Stable

Janka Hardness

1120WD

lbf

Janka (metric)

4982calc

Hardness Class

Mediumcalc

Density

0.67wd

g/cm³

MOE

10.6wd

GPa

MOR

97.1WD

MPa

Durability

Class 2

Durable

Fire (E84)

Class B

indicative

Thermal k

0.181

W/m·K

Green MC

70—

Fiber Saturation

28—

Radial Shrink

4.7WD

Tangential Shrink

8.4WD

T/R Ratio

1.79derived

Stability

Goodcalc

About the fire rating. Indicative only, derived from density and published data — not a certified rating. Real performance depends on product, thickness, coating and installation. What our ratings do and do not certify.

Compare this wood:⚖ vs Burma Teak Premium Grade ⚖ vs Neem ⚖ vs Sal All comparisons →

About European Oak

European Oak (Quercus robur) is a mid-range timber, hard enough for everyday wear and still easy to work, with a Janka hardness of 1,120 lbf (4,982 N) and a density of about 0.67 g/cm³. It grows in Europe.

At 4.7% radial and 8.4% tangential the T/R ratio is 1.79 — typical, and manageable in exterior joinery and cladding provided the gaps are designed rather than assumed. Its fibre saturation point is near 28%. Below it, movement is the governing constraint on this species: 8.4% tangential against 4.7% radial, a T/R ratio of 1.79. Flatsawn boards will cup; quartersawn stock is worth the premium here. — wide boards need real expansion room, not a token gap.

At 670 kg/m³ a cubic metre of European Oak weighs about 670 kg air-dry — that figure, the 8.4% tangential and 4.7% radial movement and the 1,120 lbf hardness are the three inputs the calculators below actually consume. Select European Oak in any of them to get species-specific results for weight, moisture, shrinkage and hardness.

Working properties

How European Oak behaves at the bench and on the machine, drawn from the USDA Forest Products Laboratory and European hardwood technical references.

MachiningMachines to a good result but works fairly hard by hand, with a tolerable-to-severe blunting effect on edges. Its open, ring-porous grain can tear on cross-grain cuts, so keep blades sharp; it turns adequately.

FasteningPre-drilling is advised for nails and screws in this dense wood. Crucially, oak's high tannin content corrodes ferrous metals — and stains blue-black around iron fixings when damp, so use stainless or non-ferrous fasteners.

GluingGlues well, but do it with care: the wood is dense and slightly acidic, and its tannins can interfere with some dye-based stains.

FinishingTakes paint, stain, oil and varnish beautifully and polishes to a high finish, with the ray figure of quartersawn stock (‘silver grain’) showing handsomely.

Steam bendingVery good for steam bending — one of the classic bending timbers, long used for boat frames and bentwork.

DryingDries slowly and is prone to splitting and shakes if rushed; patient seasoning rewards it with a stable, characterful board.

Durability & use classification

European Oak heartwood is rated durable (EN 350 Class 2) and is highly resistant to preservative treatment. The tannins and tight (tylosed) structure of this white-oak group give it genuine weather and moisture resistance — the reason it is trusted for exterior joinery and cooperage.

Typical applications & suitability

Indoor Outdoor — Comfortable both indoors and out. Durable enough for exterior joinery, timber framing and even boatwork, while remaining a premier furniture and flooring wood inside.

Documented end-uses: furniture and cabinetmaking, flooring and parquet, windows, doors and staircases, timber-frame construction, boat and harbour work, decorative veneer, and cooperage — the barrels that age wine, cognac and whisky.

Comparable species

Species closest to European Oak by density, hardness, stiffness and bending strength, computed directly from the Vriksai species dataset rather than hand-picked.

Burma Teak Premium Grade660 kg/m³ · 1070 lbf ThermoWood Birch Thermo-D620 kg/m³ · 1210 lbf White Ash600 kg/m³ · 1320 lbf Black Walnut550 kg/m³ · 1010 lbf

Trade alternatives. For similar looks and weather resistance the trade turns to Sweet Chestnut — a durable, tannin-rich European hardwood long used as an oak substitute — or thermally-modified ThermoWood OakPoor (warp-prone) dimensional stability is wanted.

Alternatives to European Oak

European Oak measures 1,120 lbf Janka at 0.67 g/cm³, EN 350 durability Class 2, movement rated Good. Because European Oak is exterior-rated at Class 2, every candidate below is too. A substitute that quietly drops a durability class is the expensive kind of mistake. Read the numbers against the Janka scale and EN 350 durability classes.

Step up — harder than European Oak

For exterior joinery, cladding and garden work that also has to resist knocks. Harder means more dent resistance but heavier sections and more machining time.

ThermoWood Birch Thermo-D1,210 lbf · 0.62 g/cm³ · Class 2+8% Janka · modified timber Iroko1,260 lbf · 0.55 g/cm³ · Class 1+12% Janka · 0.55 g/cm³ · more stable (Excellent)ThermoWood Ash Thermo-D1,320 lbf · 0.66 g/cm³ · Class 2+18% Janka · modified timber

Step down — softer than European Oak

Easier to work and lighter to fix, without dropping below the exterior durability you already have.

Hinoki Cypress1,010 lbf · 0.42 g/cm³ · Class 2-10% Janka · 0.42 g/cm³ Accoya Acetylated Radiata Pine710 lbf · 0.51 g/cm³ · Class 1-37% Janka · 0.51 g/cm³ · more stable (Exceptional)ThermoWood Radiata Pine Thermo-D710 lbf · 0.50 g/cm³ · Class 2-37% Janka · 0.50 g/cm³ · modified timber

Similar, but more dimensionally stable

Cladding boards and exterior joinery live or die on movement. These give you less of it at equal or better durability. Size the gaps with the shrinkage predictor and EMC calculator.

Accoya Acetylated Radiata Pine710 lbf · 0.51 g/cm³ · Class 1stability gained by modification, not by species · rated Exceptional vs Good · 0.7% radial movement vs 4.7%Iroko1,260 lbf · 0.55 g/cm³ · Class 1rated Excellent vs Good · T/R ratio 1.36 vs 1.79 — less cupping tendency · 3.8% tangential movement vs 8.4%Sweet Chestnut680 lbf · 0.56 g/cm³ · Class 2rated Excellent vs Good · T/R ratio 1.64 vs 1.79 — less cupping tendency · 6.9% tangential movement vs 8.4%

Closest overall match

If European Oak is unavailable and the specification cannot change, these are the nearest substitutes across hardness, density, movement, stiffness, bending strength and durability class together — not on any single property. Lower distance means a closer match.

Salmatch 1.291,340 lbf · 0.74 g/cm³ · Class 21,340 lbf vs 1,120 · 0.74 vs 0.67 g/cm³ Neemmatch 1.621,460 lbf · 0.68 g/cm³ · Class 21,460 lbf vs 1,120 · 0.68 vs 0.67 g/cm³ Sweet Chestnutmatch 1.76680 lbf · 0.56 g/cm³ · Class 2680 lbf vs 1,120 · 0.56 vs 0.67 g/cm³ · more stable (Excellent)

Computed from measured properties only — hardness, density, movement, stiffness, bending strength and EN 350 class. Price, availability and appearance are never inputs. Figures are representative values, not consignment absolutes: two species within a few percent are equivalent until verified on the material. Full method and the rules the engine cannot break.

Substituting outdoors is a match on durability class and movement first. Colour and grain can be matched later; a wrong durability class shows up as a callback in three monsoons. Where two candidates are close, compare them directly before specifying.

Compare European Oak side by side

These are the head-to-heads that decide cladding, decking and exterior joinery specifications. Every pairing shows the measured figures side by side; full matrix in the comparison index.

European Oak vs Burma Teak Premium GradeSide-by-side data · 1,070 lbf European Oak vs SalSide-by-side data · 1,340 lbf European Oak vs NeemSide-by-side data · 1,460 lbf

Calculators relevant to European Oak

Aimed at exterior detailing in European Oak: coverage, gaps, coating and durability checks. Full set in the tool index.

Wind Load Calculator for Timber Structures (IS 875)Construction Wood Expansion Gap CalculatorJoinery Wood Moisture Content TrackerWood Science Wood Acclimation Time CalculatorWood Science Compound Miter Angle CalculatorJoinery Dovetail Spacing CalculatorJoinery Smalian Formula CalculatorMeasurement Standing Tree Volume CalculatorMeasurement

Understand the figures

Strength properties — MOR, MOE and what they govern · Durability & fire — EN 350 classes and E84 ratings · Thermal conductivity — k-value and insulation behaviour · ThermoWood species guide — Thermo-D/Thermo-S treatment classes.

Further reading. What is ThermoWood? · Wood moisture content explained · How to calculate board feet.

Common questions about European Oak

How hard is European Oak, and what does that mean in practice?

At 1,120 lbf (4,982 N) it sits in the middle of the hardness range. That is hard enough for domestic flooring, worktops and furniture in normal use, and still cuts cleanly with ordinary sharp tools. It is the range most cabinet and joinery timbers fall into, which is why it is such a common choice.

Can European Oak be used outdoors without treatment?

Largely yes. It's rated Durable (Class 2) under EN 350, meaning the heartwood naturally resists decay and can handle exterior exposure — decking, cladding, garden furniture — without chemical preservatives. Two caveats worth knowing: the pale sapwood isn't durable, so it should be cut away for outdoor work, and 'durable' isn't 'immortal' — it'll still silver and weather, so a UV oil keeps the colour if you care about looks.

Is European Oak prone to cupping or warping?

It needs a little respect here. Its tangential shrinkage (11.0%) is well above its radial (4.6%) — a T/R ratio of roughly 2.39 — which means the wood moves unevenly as it dries and can cup if you rush it. The fix is straightforward: use properly seasoned, quarter-sawn boards where you can, acclimatise the timber to the room before fixing, and don't trap it without room to breathe.

unverified no published source for this figure · WD The Wood Database (Eric Meier) · calc derived from the figures above · — no published source found

Tools that use this species

Janka Database ToolHardness for 60 species Green Weight CalculatorWeight of green timber Shrinkage PredictorDimensional movement EMC CalculatorEquilibrium moisture content Fiber Saturation CalculatorFSP by species Volume Converterm3, CFT, board feet

Sources & references

The Wood Database (Eric Meier) — compiled species data, one of the references behind the panel above. Which figure comes from which reference is not recorded field by field. Spot checks show the numbers do trace to published sources, but not all to the same one: strength values for US species follow the USDA FPL Wood Handbook exactly, while European species draw on European references instead. So a figure that disagrees with any single reference here is not necessarily wrong — different bodies measure specific gravity and shrinkage on different bases. If a number matters to your work, check it against the reference you intend to rely on.
USDA Forest Products Laboratory — Wood Handbook (FPL-GTR-282), white-oak group · species background and working data
European hardwood technical references — europeanwood.org / joinery-grade oak specifications · working, tannin/ferrous behaviour, uses
EN 350 — European standard for natural durability of wood · durability class

Updated 15 Jul 2026 Values are representative; wood varies with provenance, age and grade. Confirm critical structural or fire figures against a test report for your actual product.