Thermowood cladding · Milled in Greenville, SC
American-milled thermowood, priced for real projects.
At your door in 2–4 weeks.
Why thermowood
Heat and steam. Nothing else.
At 212 °C, heat and steam permanently change the cell structure of the wood. What comes out of the kiln behaves differently than the wood that went in — and keeps behaving that way for decades.
Durability
Class 1–2 rot resistance
The most durable class a softwood can reach (EN 350), rated 25+ years above ground — and backed by our 25-year warranty against rot and decay.
Stability
Half the movement
Equilibrium moisture drops by roughly half, so boards swell and shrink far less through seasons. Joints stay tight, lines stay straight.
Chemical-free
Nothing to leach, ever
No copper, no borates, no film. Safe to cut, sand, and burn as offcuts. The color runs all the way through the board.
Weathering
Ages to silver, honestly
Left uncoated, the honey-brown face weathers to an even silver-grey patina — expected weathering, not a defect. Oil it if you'd rather keep the roast tone.
Four categories
A board for every surface.
01
Exteriors
Cladding
Tongue-and-groove, open-joint, and rainscreen profiles in pine, radiata, and ayous.
02
Outdoor living
Decking
Stable through freeze-thaw cycles, splinter-free, and cooler underfoot than composite.
03
Interiors
Interior
Aspen and pine paneling for walls, ceilings, and feature surfaces.
04
Heat & steam
Sauna
Aspen and radiata — the two woods Finland has always trusted next to the stove.
Straight math
Better than cedar. Fraction of composite.
Thermowood outlasts clear cedar on durability and stability, and holds its own against composite — while staying a real, workable wood.
Relative material cost for comparable exterior boards. Request a quote for current pricing.
Samples
Hold it first.
Eight 8-inch boards across all four species, with color cards showing the fresh-milled tone and the weathered patina, and profile cross-section cards for your drawings. $19, credited back on any order over $200.
The fastest way to understand thermowood is to hold it. Feel the weight, check the profile against your section, and leave a board on the client's table.
Send square footage and a profile — or just a drawing — and we'll price it within one business day. Most orders ship in 2–4 weeks.