Teak
Tectona grandis
Also known as Burma teak, plantation teak, sagwan, saigun · Botanical Tectona grandis
Revision history
- — Data re-verified in site-wide audit (formulas, sources, durability classes)
- — Working properties and comparable-species data cross-checked against listed sources
About Teak
Teak (Tectona grandis) is a mid-range timber, hard enough for everyday wear and still easy to work, with a Janka hardness of 1,070 lbf (4,759 N) and a density of about 0.55 g/cm³. It grows in India and South Asia.
At 2.6% radial and 5.3% tangential the T/R ratio is 2.04 — 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 modest at 5.3% tangential, but the 2.04 T/R ratio means one-sided sealing will still pull a panel out of flat.
At 550 kg/m³ a cubic metre of Teak weighs about 550 kg air-dry — that figure, the 5.3% tangential and 2.6% radial movement and the 1,070 lbf hardness are the three inputs the calculators below actually consume. Select Teak in any of them to get species-specific results for weight, moisture, shrinkage and hardness.
Working properties
How Teak behaves at the bench and on the machine, drawn from the CIRAD Tropix tropical-wood database and PROTA / Useful Tropical Plants species records.
Durability & use classification
Teak heartwood is rated very durable (EN 350 Class 1). Per the CIRAD Tropix assessment it naturally reaches EN 335 use class 5 — the highest class, covering permanent exposure in marine or brackish water — and is resistant to Teredo (marine borers). The pale sapwood is not durable and is normally cut away for exterior and marine work.
Typical applications & suitability
Indoor Outdoor Marine — Teak is one of relatively few timbers rated for prolonged exterior, and even marine, service in its heartwood without preservative treatment.
Documented end-uses (CIRAD, PROTA, FAO): boat decks and marine construction; bridges, docks, quays and floodgates; exterior joinery, doors and cladding; high-end and garden furniture; flooring; and decorative veneer.
Comparable species
Species closest to Teak by density, hardness, stiffness and bending strength, computed directly from the Vriksai species dataset rather than hand-picked.
Trade alternatives. Where genuine teak is cost- or supply-constrained, the timber trade commonly substitutes Iroko (often sold as “African teak”) and, for exterior deck and marine work, dense durable hardwoods such as Cumaru. Match on durability class and movement, not appearance alone.
Alternatives to Teak
Teak measures 1,070 lbf Janka at 0.55 g/cm³, EN 350 durability Class 1, movement rated Moderate. Because Teak is exterior-rated at Class 1, 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.
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.
Easier to work and lighter to fix, without dropping below the exterior durability you already have.
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.
If Teak 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.
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 Teak 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.
Calculators relevant to Teak
Aimed at exterior detailing in Teak: coverage, gaps, coating and durability checks. Full set in the tool index.
Understand the figures
Janka hardness scale — how the lbf figure is measured · Wood density reference — oven-dry vs air-dry basis · Moisture content — EMC, FSP and service conditions · Strength properties — MOR, MOE and what they govern.
Further reading. ThermoWood vs Teak · Wood moisture content explained · How to calculate board feet.
Common questions about Teak
unverified no published source for this figure · FPL USDA FPL Wood Handbook GTR-190 · WD The Wood Database (Eric Meier) · calc derived from the figures above