Fluted slats. Tight grooves. A lot of visual interest per square foot.
The PROSAUNAS Thermo-Aspen Groove-S 1×3 T&G Wall Cladding is 0.59″ thick, 2.36″ wide per board, with a 2.1″ coverage that leaves a narrow, precise shadow groove between boards. Available in 1, 5, and 10-foot lengths. It’s the profile designers reach for when they want a sauna wall to read as a design element rather than a utility finish.
Why Thermo-Aspen
Narrow-profile cladding is where thermal modification pays off most visibly. An untreated 1×3 board in a sauna will absorb moisture, swell against its neighbor, and eventually close or distort the groove. In thermo-aspen, the heat-and-steam process changes the wood at a cellular level so it can’t hold moisture and won’t move. The groove stays the width you installed it. The warm golden-brown color runs all the way through the board, so a trimmed end at the wall height matches the face grain and the room looks consistent.
Worth being straight about: this is a thinner board (0.59″) compared to a Grace or a bench plank. It’s wall and ceiling cladding, not structural paneling. And the narrow coverage means you’ll use more linear feet to cover a given surface area than with a wider board. Do the math before you order, and reach out if you want us to check it. We send free samples so you can see the groove depth and spacing in person first.
Specifications
- SKU: PS-THERMO-ASPEN-GROOVE-S-1X3-TG
- Species: Thermally modified aspen
- Profile: Groove-S 1×3 T&G, narrow shadow groove, rounded edges
- Thickness: 0.59″
- Width: 2.36″
- Coverage per board: 2.1″
- Available lengths: 1 ft, 5 ft, 10 ft
- Price: $5.98 per linear foot (MAP)
- Made in: Estonia
Where it goes
Feature walls and ceilings where you want strong linear rhythm. Strikes a great contrast when used as an accent alongside a plainer STS4 cladding or a thick Grace board on the other walls. Also works well as a ceiling-only material where the fluted shadow pattern catches the overhead light differently than flat cladding.
Shipping and samples
Sold by the linear foot. Shipping is a flat $795 to the continental US, or free when you order with a heater. Free samples available. Text your name and address to (844) 565-1113.
Call Ben² at (844) 565-1113 if you’d like to talk through the board count before you order.
Prebuilt
Sauna Brushes
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