Cedar Sense Articles
Cedar vs Thermowood Sauna: Which Is Better?
Short answer: both make great saunas. Cedar is the classic choice: it smells wonderful, resists rot naturally and has a warm, light look. Thermowood (wood that’s been heat-treated) is darker, more stable and lower-maintenance outdoors, with almost no smell. If you love the cedar aroma, go cedar. If you want the least upkeep and a modern dark look, go thermowood.
We’re Cedar Sense, a family sauna business in Waubun, Minnesota. We sell both, as finished saunas and as cedar and thermo-aspen boards for people building their own.
Cedar vs thermowood at a glance
| Cedar | Thermowood | |
|---|---|---|
| What it is | Natural Western Red Cedar or Eastern White Cedar | Spruce, pine or aspen heated to roughly 350 to 450°F in a low-oxygen kiln |
| Smell | Strong, sweet cedar aroma | Mild toasted smell when new, then almost none |
| Look | Light to reddish brown, often knotty | Even, darker brown |
| Rot resistance | Good, from natural oils | Very good, because heat removes the sugars rot feeds on |
| Stability | Good | Very good: it swells and shrinks less |
| Upkeep outside | Stain or seal the exterior to slow graying | Less upkeep; it also grays in sun unless finished |
| Strength | Soft, dents easily | A bit more brittle; edges can chip |
| Best for | Classic look and aroma | Low maintenance and a modern look |
Why people choose cedar
Cedar has been the go-to sauna wood in North America for decades. Its natural oils help it resist rot and insects, it’s light enough to heat up fast, and the aroma when you pour water on the rocks is a big part of the experience. Western Red Cedar has a reddish color and knots; Eastern White Cedar is lighter with tight knots.
The trade-offs: cedar is soft, so it dents, and the outside turns silver-gray in the sun unless you stain or seal it. A small number of people are sensitive to cedar dust or its strong smell.
Cedar saunas we sell include the Minnesota-built Setri barrels (assembled, from $6,490) and the Canadian Timber Eastern White Cedar kits (from $6,390). See all cedar saunas.
Why people choose thermowood
Thermowood starts as ordinary spruce, pine or aspen. Heating it in a kiln without much oxygen cooks out the sugars and resins, which makes the wood darker, much more stable and very resistant to rot. It won’t bleed resin in the heat, and it holds its shape through hot and cold cycles, which is why many Nordic sauna builders use it.
The trade-offs: it has almost no aroma, it’s a little more brittle, and scratches show lighter wood underneath. It still grays in direct sun unless the exterior is finished.
Thermowood saunas we sell include the SaunaLife Thermo-Spruce barrel kits (from $4,390) and the Finnmark FD-7 in Thermo-Aspen. See all thermowood saunas.
What about the benches?
Many saunas mix woods: cedar or thermowood walls with aspen or thermo-aspen benches. Aspen is smooth, nearly knot-free and has no resin, so it stays cooler to sit on. If you’re building your own, that’s the combination we recommend.
Which should you pick?
- You want the classic sauna smell: cedar.
- You want the least maintenance outdoors: thermowood.
- Someone in the house is sensitive to strong smells: thermowood, or cedar walls with aspen benches.
- You’re building indoors or on a budget: either works; for DIY, compare our cedar and thermo-aspen boards, which ship free.
Common questions
Is cedar or thermowood better for a sauna?
Both are excellent. Choose cedar if you want the classic cedar smell and a lighter look. Choose thermowood if you want a darker, very stable wood that needs less upkeep outdoors. For benches, thermo-aspen or aspen stays cooler to the touch than cedar.
Does thermowood last longer than cedar?
Thermowood is very stable and resists rot well. SaunaLife says its Thermo-Spruce lasts up to twice as long as cedar outdoors. A well-built cedar sauna on a good base with a roof also lasts for decades.
Does thermowood smell like cedar?
No. New thermowood has a mild, toasted smell that fades. Cedar has a strong, sweet aroma that many people love and that stays noticeable when the sauna is hot.
Is thermowood more expensive than cedar?
It depends on the brand and grade. At Cedar Sense, thermowood barrel kits start at $4,390 and assembled cedar barrels at $6,490, but much of that gap is kit versus assembled, not the wood.
What wood is best for sauna benches?
Aspen or thermo-aspen. They are smooth, have few knots and no resin, and stay cooler to the touch than cedar.
Still deciding? Call or text Mike at 218-760-2041, or read our best barrel saunas guide.
