Every sauna has its own ambiance—some lean practical, others feel like sculpture. But no matter how you design yours, a few rules always stand: choose woods that stay cool to the touch, don’t release resin, and can handle heat and moisture without breaking a sweat.
With our expertly crafted thermal modification process using only heat and steam, our wood becomes more durable, more stable, more moisture-resistant—and richer in color. Some species keep their soft, golden tones. Others, like magnolia, radiata pine, and ash, deepen into bold, elegant shades. No chemicals. Just science, heat, and clean design.
Here’s our guide to the most popular woods we use to build beautiful, long-lasting saunas.
Common Aspen (Populus tremula)
Aspen is a staple for sauna interiors—smooth, light-toned, knot-free, and easy on the skin. It doesn’t get too hot, doesn’t splinter, and doesn’t secrete resin, making it a safe and comfortable choice for benches. Its clean look also works beautifully on interior walls or painted surfaces.
*Available in natural or medium modification
Common Alder / Black Alder (Alnus glutinosa)
Alder brings a warm reddish tone and a fine, pleasing texture—an inviting upgrade for interior finishes. This hardwood stays cool, repels moisture, and holds up well in demanding sauna conditions. Natural or thermally modified, alder offers a beautifully consistent appearance from wall to wall.
*Available in natural, medium, or intense modifications
Norway Spruce (Picea abies)
Spruce is one of the lightest-colored conifers, with a soft white tone and a subtle yellow undertone. It’s commonly used for sauna exteriors thanks to its clean look and versatility. Brushed finishes help emphasize its natural pattern, giving spruce a refined, modern edge.
*Available in intense modification
Magnolia (Liriodendron tulipifera)
Magnolia—often called tulip tree—brings a creamy, golden tone with a distinctive grain similar to ash or radiata pine. Lightweight and low-density, it’s an excellent option for benches and interior surfaces. After thermal modification, magnolia deepens into a rich, dramatic shade that instantly elevates any sauna environment.
*Available in medium modification
Radiata Pine (Pinus radiata)
Fast-growing and beautifully consistent, radiata pine offers smooth, knot-free boards that stay cool and comfortable—perfect for benches. Thermal modification darkens the wood and highlights its grain, resulting in wide, luxurious boards that feel at home in both modern and traditional sauna designs.
*Available in intense modification
Scots Pine (Pinus sylvestris)
Scots pine is one of the most widespread pine species worldwide, and it responds exceptionally well to thermal modification. Its natural character and visible grain bring an organic, rustic warmth to sauna exteriors, while brushing techniques can amplify its texture for a more architectural feel. We offer it in both natural and thermo-treated options.
*Available in intense modification
American Ash / White Ash (Fraxinus americana)
Strong, durable, and naturally elegant, American ash brings a bold architectural presence. When thermallymodified, it shifts into deep brown tones that feel rich and sophisticated. Ash is a standout choice for exterior cladding and high-end interior
accents.
*Available in intense modification
Ready to design your dream sauna? Visit our sauna collection to get started.
Photo Credits: Karl Kasepõld. Elvo Jakobson.
