Oak GREEN
Print state
GREEN = freshly sawn, MC above fibre saturation
Choose only for wet-service or riving/steam-bending work; strength and stiffness are 30–45 % below dry values and shrinkage is still to come.
Values for the GREEN condition
Other Oak tempers and conditions
Oak is listed in 3 conditions; see the grade overview at Oak.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
GREENThis page Freshly sawn, MC above fibre saturation | Choose only for wet-service or riving/steam-bending work; strength and stiffness are 30–45 % below dry values and shrinkage is still to come. | — | 70 | 1.4 | — | 0.35 W/m·K |
Red oak | Cheaper, slightly softer and more open-pored than white oak; fine for interior furniture and flooring but not for wet or outdoor use. | — | 92 | 1 | — | 0.17 W/m·K |
White oak | Pick white oak when liquid-tightness, steam-bending or outdoor decay resistance matters (tyloses-blocked pores, DC2 heartwood). | — | 100 | 1 | — | 0.18 W/m·K |
What is Oak GREEN?
Oak GREEN is Oak in the GREEN condition — choose only for wet-service or riving/steam-bending work; strength and stiffness are 30–45 % below dry values and shrinkage is still to come. Oak GREEN has a tensile strength of 70 MPa (10.2 ksi), stronger than 67% of natural material grades. Elongation at break is 1.4% and the elastic modulus is 9.6 GPa (1.39 Msi). Oak GREEN has a density of 1 g/cm³ (0.0361 lb/in³), heavier than 79% of natural material grades.
Advantages
- Conducts heat well — 0.35 W/m·K (0.202 BTU/hr·ft·°F), better than 81% of natural material grades
Limitations
- Needs corrosion protection — 20/100, worse than 98% of natural material grades
- Difficult to machine — 55/100, worse than 91% of natural material grades
- Heavy — 1 g/cm³ (0.0361 lb/in³), worse than 79% of natural material grades
Oak GREEN properties
Typical room-temperature values for Oak GREEN; 10 are specific to this condition. Other listed values are Oak reference data and may not represent this condition. Bars are the position among natural material grades.
Physical2
Oak GREEN has a density of 1 g/cm³ (0.0361 lb/in³), heavier than 79% of natural material grades.
Mechanical10
Oak GREEN has a tensile strength of 70 MPa (10.2 ksi), stronger than 67% of natural material grades. Elongation at break is 1.4% and the elastic modulus is 9.6 GPa (1.39 Msi).
Thermal5
Oak GREEN is rated for continuous service to 90°C (194 °F). It conducts heat at 0.35 W/m·K (0.202 BTU/hr·ft·°F), better than 81% of natural material grades. Thermal expansion is 4.5 µm/m·K (2.5 µin/in·°F).
Electrical2
Oak GREEN is an electrical insulator with a dielectric strength of 4 kV/mm (101.6 V/mil) and a resistivity of 1×10¹⁰ Ω·m.
Chemical & Environmental1
Corrosion resistance is poor (20/100), worse than 98% of natural material grades.
Sustainability4
Producing a kilogram of Oak GREEN takes about 11 MJ of energy and emits 0.55 kg of CO₂ — more than 56% of natural material grades. Typical recycled content is 5%.
Manufacturability2
Oak GREEN's machinability is good (55/100, worse than 91% of natural material grades).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Oak GREEN
Is Oak easy to machine?
Cuts, turns and bores cleanly with carbide tooling and 20–25° rake; high silica-free but abrasive tannin/density causes moderate tool wear, and torn grain around rays needs sharp knives and light finishing cuts.
Can Oak be welded?
Not weldable — joined by PVA/PU/epoxy adhesives or mechanical joinery; pre-bore for screws and use stainless or hot-dip galvanised fasteners because tannins corrode plain steel and cause black staining.
Can Oak be formed, bent or molded?
White oak is one of the best steam-bending hardwoods (radius down to ~2–3× thickness with a compression strap); red oak bends poorly and splits, and all oak must be dried slowly to avoid honeycomb and surface checking.
What surface finishes work on Oak?
Sands and stains readily but the open ring-porous grain needs a pore filler for a mirror finish; ammonia fuming or iron-acetate reacts with tannins for classic darkening, and oil, wax, lacquer or 2K PU all adhere well.
Oak chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| celluloseoven-dry wood basis | 40 – 47 | 44 |
| hemicellulosemainly glucuronoxylan in hardwoods | 18 – 26 | 22 |
| ligninsyringyl/guaiacyl hardwood lignin | 20 – 28 | 24 |
| extractives (tannins, phenolics)high ellagitannin content; stains steel and darkens with iron | 2 – 10 | 6 |
| ash (inorganics) | 0.2 – 0.8 | 0.4 |
| organic matrixbalance of cell-wall constituents | balance | — |
Oak GREEN — frequently asked
What is Oak GREEN used for?
Oak GREEN is typically used for flooring, furniture, cabinetry, barrel staves and structural beams. In short: benchmark structural hardwood; best steam-bending hardwood; hard-wearing flooring choice.
What is the tensile strength of Oak GREEN?
Oak GREEN has a typical tensile strength of 70 MPa (10.2 ksi) — stronger than 67% of natural material grades. Strength varies by condition: see the 3 listed tempers.
Is Oak GREEN easy to machine?
Reasonably — machinability is rated good (55/100, worse than 91% of natural material grades). Cuts, turns and bores cleanly with carbide tooling and 20–25° rake; high silica-free but abrasive tannin/density causes moderate tool wear, and torn grain around rays needs sharp knives and light finishing cuts.
Can Oak GREEN be welded?
Not weldable — joined by PVA/PU/epoxy adhesives or mechanical joinery; pre-bore for screws and use stainless or hot-dip galvanised fasteners because tannins corrode plain steel and cause black staining.
What surface finishes work on Oak GREEN?
Sands and stains readily but the open ring-porous grain needs a pore filler for a mirror finish; ammonia fuming or iron-acetate reacts with tannins for classic darkening, and oil, wax, lacquer or 2K PU all adhere well.
Can Oak GREEN be formed, bent or molded?
White oak is one of the best steam-bending hardwoods (radius down to ~2–3× thickness with a compression strap); red oak bends poorly and splits, and all oak must be dried slowly to avoid honeycomb and surface checking.
What is the maximum service temperature of Oak GREEN?
Oak GREEN is rated for continuous use to about 90°C (194 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Wood Handbook — Wood as an Engineering Material (FPL-GTR-282), Ch. 5 Mechanical Properties — USDA Forest Products Laboratory (2021)
- ASTM D143 — Standard Test Methods for Small Clear Specimens of Timber — ASTM International (2022)
- ASTM D9 — Standard Terminology Relating to Wood and Wood-Based Products — ASTM International (2021)
- EN 13556 — Round and sawn timber: nomenclature of timbers used in Europe (QURO / QUPE) — CEN (2003)
- EN 350 — Durability of wood and wood-based products: natural durability classes — CEN (2016)
- CES EduPack eco-audit data, hardwood (oak) lumber — Granta/Ansys (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.