Thermally modified exterior and indoor-outdoor flooring

Continuous floors that run from the living room out onto the terrace, in thermally modified Ash, Iroko, Radiata Pine, knotty European Pine, Rhino Wood and reclaimed barn wood.

Thermally modified wood
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From living room to terrace on one continuous wood floor.

An indoor-outdoor floor has to look like furniture inside and survive weather outside. Thermal modification gives boards the stability to cross a threshold without gapping or cupping, and the decay resistance to sit in sun and rain.

floors

Crosses the threshold

One board inside and out, no change in look.

Three faces

Smooth, fine-ribbed anti-slip and wide-groove.

Rot and insect resistant

Without chemical preservatives.

Long Pine boards

Radiata and Knotty Pine to 16.4 ft.
Why specify thermowood floors

Floors that hold their line in sun and rain

Heat-and-steam treatment drives out the sugars and moisture that make ordinary timber swell, cup and decay. The result is a dimensionally stable board that stays tight at the joints and true underfoot, indoors and out, with minimal maintenance. Every board is milled to order.

6 species

Ash, Iroko, Radiata Pine, Knotty Pine, Rhino Wood and barn wood.

Anti-slip faces

Fine-ribbed and wide-groove profiles for wet areas.

Fire-retardant option

Backed by ASTM and ULC test reports.

Milled to order

Cut to your thickness, width and length.

Profiles, species

Six species, three faces

Smooth, fine-ribbed anti-slip and wide-groove faces. Hardwoods from 13/16 in to 1-5/8 in thick; Pine boards in 1 in and 1-5/8 in up to 16.4 ft long. Rhino Wood in 2-9/16, 3-15/16 and 5-3/8 in widths.

thermally modified Iroko exterior flooring (ThermoWood Millworks)

Iroko

Dense African hardwood with a rich golden-brown tone and premium hardness.
Rhino Wood cladding (ThermoWood Millworks)

Rhino Wood

Densified, wax-infused Pine as hard as tropical hardwood, Class 1 durability.

Heat and steam only, no chemicals, made in the USA

Thermal modification uses only heat and steam. Our thermowood is sourced from certified renewable forests and milled in the USA; the boards are 100% natural, fully recyclable and can go to bio-energy at end of life.

Silver or warm

Thermally modified Ash

Ash weathers to an even silver-grey outdoors or holds a warm brown when oiled. 13/16, 1 and 1-5/8 in thick, 3-9/16 to 5-1/2 in wide.

thermally modified Ash decking (ThermoWood Millworks)
thermally modified Radiata Pine cladding (ThermoWood Millworks)
Long boards

Radiata and Knotty Pine

Plantation radiata gives an even warm tone at an accessible price; knotty European Pine brings rustic character. Both run 3.3 to 16.4 ft.

Character floor

Reclaimed barn wood

Sustainably salvaged boards, thermally modified for outdoor use, with weathered texture that varies from lot to lot. Ask for current stock.

reclaimed barn wood cladding (ThermoWood Millworks)
thermally modified Ash decking (ThermoWood Millworks)
Thermally modified Ash

13/16 to 1-5/8 in

thermally modified Iroko exterior flooring (ThermoWood Millworks)
Iroko

Golden-brown hardwood

thermally modified Radiata Pine cladding (ThermoWood Millworks)
Radiata Pine

Lengths to 16.4 ft

Rhino Wood cladding (ThermoWood Millworks)
Rhino Wood

Ipe-like hardness

Species

6

Faces

3

Max length

16.4 ft

Made in

USA

Sizes by species

Decking and exterior floors

Decking, porch and exterior flooring boards come in three faces: smooth, fine-ribbed anti-slip and wide-groove. Pine boards run longest; hardwood boards are available thicker.

SpeciesThicknessWidthLength
Ash13/16″, 1″, 1-5/8″3-9/16″ to 5-1/2″3.3 to 9.8 ft
Iroko13/16″, 1″, 1-5/8″3-9/16″ to 5-1/2″2.6 to 9.8 ft
Radiata Pine1″, 1-5/8″3-5/8″ to 5-7/16″3.3 to 16.4 ft
Knotty European Pine1″, 1-5/8″3-5/8″ to 5-7/16″3.3 to 16.4 ft
Rhino Wood13/16″, 1″2-9/16″, 3-15/16″, 5-3/8″to order
Reclaimed barn woodSized per lot, ask for current stock

Plain planed face for covered terraces and interiors.

Shallow ribs for grip around pools and in wet areas.

Deep grooves that drain water and give a bold deck look.

Exterior floor questions

Common questions

Installation guides for cladding, decking and porch flooring are on our guides page.

Flooring made from thermally modified wood for continuous indoor-outdoor floors, treated with heat and steam only for rot and insect resistance and dimensional stability.

Choose the fine-ribbed anti-slip or wide-groove face for pool surrounds and wet terraces; the smooth face suits covered areas and interiors.

Ash and Iroko in 13/16, 1 and 1-5/8 in thick, 3-9/16 to 5-1/2 in wide, up to 9.8 ft; radiata and Knotty Pine 1 and 1-5/8 in thick up to 16.4 ft; Rhino Wood in three fixed sizes.

Yes. A fire-retardant treatment backed by ASTM and ULC test reports is available; classification depends on species, profile and application.

Yes, we ship worldwide. Orders go by freight across the US and overseas, with weekly truck delivery across Los Angeles, Orange County and San Diego.

Download the install guides