DuraTau® Thermally Modified Decking

Q: Is Tauari an oak?

No. Tauari is Couratari , in the Brazil-nut family. It is sold as Brazilian Oak because the raw wood looks and works much like oak. It has nothing to do with the oaks botanically.

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DuraTau Thermally Modified 5/4x6 Deck Board

from $6.36/LF

DuraTau® is thermally modified Tauari, a Latin American hardwood best known as flooring and sometimes sold as Brazilian Oak. It goes into the kiln pale and comes out a warm golden brown, colored through the board.

Most thermally modified decking starts as a soft or medium-density wood, and the process makes it softer still. Tauari starts out dense, so DuraTau comes out of the kiln with real hardwood numbers: 1,330 lbf Janka, about twice Korina, with shrinkage under 2% and Class 1 durability.

No preservatives, no copper, nothing added but heat and steam. We stock it as a First Clear 5/4x6 deck board in even lengths from 8′ to 20′, from $6.36/LF, with a 25-year warranty.

DuraTau decking at a glance

Property	DuraTau®
Species	Tauari (Couratari spp.), family Lecythidaceae; also sold as Brazilian Oak
Origin	Latin America
Janka hardness	1,330 lbf
Density	510 kg/m³ (after modification)
Modulus of rupture	12,100 psi
Modulus of elasticity	1.8 million psi
Shrinkage	Under 2% radial and tangential
Durability	Class 1 (very durable)
Color	Warm golden brown, wheat-toned, all the way through
Grain & texture	Even to straight grain; fine texture, medium luster
Grade	First Clear
Chemicals added	None: heat and steam only
Warranty	25 years
Stocked at Ghent	5/4x6 S4S E4E, even lengths 8′–20′

Why DuraTau

Hardwood hardness, after modification

1,330 lbf Janka and 12,100 psi MOR once modified. Starting dense means DuraTau keeps the strength, stiffness and dent resistance that softer modified woods give up.

Stays flat

Shrinkage under 2% in both directions. Boards resist cupping, warping and swelling, so gaps stay even and the surface stays smooth through the seasons.

A smoother deck

The tight, uniform grain resists surface checking and splintering, and First Clear grade means clear faces board after board.

Nothing added

No copper, no preservatives, nothing to leach into soil or run off the deck. The color and the decay resistance are the wood itself, right through to a fresh cut end.

How thermal modification works

Thermally modified wood is real wood changed with heat and steam alone, in a sealed, oxygen-free kiln at roughly 180–230°C.

Drying. The wood is heated gradually and its moisture driven to near zero.
Modification. At full temperature the cell structure is permanently altered: the hemicellulose that decay fungi feed on breaks down, and the wood loses much of its ability to take on water.
Conditioning. The wood is cooled and brought back to a stable working moisture content with steam.

The result absorbs far less moisture, so it moves far less, and the color changes all the way through. See the thermally modified wood overview for the full range.

DuraTau vs Korina vs Ipe

	DuraTau®	Korina	Ipe
What it is	Thermally modified Tauari	Thermally modified Frake	Natural tropical hardwood
Janka	1,330 lbf	670 lbf	3,680 lbf
Density	510 kg/m³	573 kg/m³	1,050 kg/m³
Shrinkage	Under 2%	Under 2%	About 5%
Chemical-free	Yes	Yes	Yes
CITES listed	No	No	Yes, since 2022
Color	Warm golden brown	Golden to chocolate brown	Deep brown to near-black
Warranty	25 years	Ask us	25 years
5/4x6 from	$6.36/LF	$5.35/LF	$9.25/LF

Keep the gold, or let it silver

Left bare, DuraTau weathers to the soft silver-grey every exterior wood reaches.

Nothing is lost when it does: the decay resistance is in the wood, not in a coating. To hold the golden brown, DuraTau takes oil- and water-based stains and paint easily, and a penetrating stain refreshes without stripping.

ExoShield wood stain

Rooftop terrace decked in DuraTau beside a charred-black timber wall

DuraTau sizes

5/4x6 S4S E4E: the deck board, eased on all four edges, net 25 × 139 mm (about 1″ × 5-1/2″), First Clear, even lengths 8′ to 20′, from $6.36/LF.

Priced by the lineal foot: build your tally on the product page and pay for the lengths your deck needs. DuraTau is also produced in 4/4x4, 4/4x6 and 5/4x4; ask us if your project needs one of those. Full specifications are on the DuraTau product sheet (PDF).

Installing DuraTau decking

It cuts, sands and finishes like a fine-grained hardwood, with the one caution that applies to all thermally modified wood: it is more brittle than raw stock.

Pre-drill near board ends and at every face fastener.
Stainless steel fasteners, 304 or 316. For a clean surface, ExoDek QuickClip is the recommended hidden fastener.
Keep carbide tooling sharp. Dull blades tear rather than cut modified wood, and collect the fine dust.
Adhesives: MUF, PU and STP all bond to it.
No further seasoning. It leaves the kiln at low moisture content and moves very little on site.
Never structural. Joists, beams, posts and stringers in something else; DuraTau is the walking surface.

See the decking installation guide before you start.

DuraTau decks

DuraTau — common questions

What is DuraTau?

DuraTau® is thermally modified Tauari, a Latin American hardwood. It is modified with heat and steam only, which makes it dimensionally stable and very durable, and turns it a warm golden brown through the board.

Is Tauari an oak?

No. Tauari is Couratari, in the Brazil-nut family. It is sold as Brazilian Oak because the raw wood looks and works much like oak. It has nothing to do with the oaks botanically.

DuraTau or Korina?

Both are chemical-free, thermally modified and move under 2%. DuraTau starts from a denser wood, so it is about twice as hard (1,330 vs 670 lbf Janka), stronger, and carries a 25-year warranty; it is golden brown where Korina runs to chocolate. Korina costs less per foot.

DuraTau or Ipe?

Ipe is harder and denser and lasts longer than anything else we sell. DuraTau moves less, is lighter to handle, is not CITES-listed, and costs about a third less per foot. Both carry a 25-year warranty.

Is there a warranty?

Yes: DuraTau carries a 25-year warranty, provided the installation guidelines are followed.

Can DuraTau be used structurally?

No. Thermal modification makes wood more brittle, whatever the species. Use DuraTau for decking, siding, soffits and trim, and frame the structure in something else.

Does the color fade?

The surface greys under UV like any exterior wood, but the brown runs through the board. Stain it to keep the color, or let it silver without losing durability.

What fasteners should I use?

304 or 316 stainless steel. ExoDek QuickClip is the recommended hidden fastener.

What sizes do you stock?

5/4x6 S4S with eased edges, First Clear, in even lengths 8′ to 20′, from $6.36/LF. 4/4x4, 4/4x6 and 5/4x4 are produced too; ask us.

Price a DuraTau deck

Build your tally on the product page, or send us the dimensions and we will come back with a tally and a delivered price. Comparing species? See the decking comparison, the hardwood decking guide, or the technical profile on the DuraTau species page.

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