Cedar vs. Thermally Modified Wood for Saunas
Cedar is aromatic and naturally rot-resistant; thermally modified wood is extra-stable and durable. Here is how cedar and thermowood compare for saunas.
The short answer
Cedar is naturally aromatic, stable and rot-resistant, the classic choice; thermally modified (thermowood) timber is heat-treated for extra dimensional stability and rot resistance, often with a darker tone and low scent. Both make excellent, durable sauna wood.
Cedar has long been the default premium sauna wood, but thermally modified timber — often called thermowood — has become a strong alternative, especially for exteriors and stable interiors. Here is how they compare.
Western red cedar
The traditional premium choice: dimensionally stable, naturally rot-resistant, warm-toned, and famous for its aroma.
Cedar
- Warm, characteristic aroma
- Naturally stable and rot-resistant
- Attractive warm colour
- The classic sauna wood
Trade-offs
- More expensive
- Aroma bothers a scent-sensitive minority
Thermally modified wood
Timber (often aspen, pine or other species) heat-treated to improve stability and rot resistance, with a darker tone and low scent.
Thermowood
- Extra dimensional stability
- Improved rot and moisture resistance
- Rich, darker tone
- Low scent — good for the scent-sensitive
Trade-offs
- Can be more brittle
- Darker look is a matter of taste
- Less aromatic character
How to choose
| Priority | Choose |
|---|---|
| Aroma | Cedar |
| Maximum stability | Thermowood |
| Warm, light tone | Cedar |
| Rich, dark tone | Thermowood |
| Minimal scent | Thermowood |
Benches either way
Whatever you clad the walls in, use cool, knot-free bench wood — cedar, aspen or alder — where your skin rests. Both cedar and thermowood are left bare and cared for by light sanding, never sealed. For the broader wood picture, see our interior wood guide and the cedar vs. hemlock comparison.
Both woods reward the same simple care: keep them bare so they can breathe, clean gently, and refresh with light sanding rather than sealing. Treated this way, cedar and thermowood alike stay handsome and durable in the demanding heat and humidity of a sauna for many years.
Where each wood suits the build
Because both cedar and thermowood are excellent, it often comes down to where in the sauna each is used and the look you want. Thermowood shines on exteriors and on surfaces exposed to moisture, thanks to its enhanced stability and rot resistance, and it gives a rich, darker tone that many find striking. Cedar shines where its warm aroma and light colour can be enjoyed, and it remains the classic choice for a traditional feel.
Many builds combine them — thermowood on the exterior or moisture-exposed areas, cedar or a cool wood like aspen or alder for the benches your skin touches. Whatever the combination, all sauna wood is left bare and cared for by light sanding, never sealed, so it can breathe and absorb the humidity of each session. Choose on aroma, tone and where the wood sits, and either — or a thoughtful mix — gives a durable, handsome interior that lasts for years.
Frequently asked questions
Is cedar or thermowood better for a sauna?
Both are excellent. Cedar is aromatic, stable and rot-resistant with a warm tone; thermally modified wood is extra-stable and rot-resistant with a darker, low-scent finish. Choose on aroma, tone and stability preference.
What is thermally modified sauna wood?
Timber heat-treated to improve its dimensional stability and rot resistance, often with a darker tone and low scent. It is popular for sauna exteriors and stable, moisture-exposed interiors.
Does thermowood smell like cedar?
No — thermally modified wood has low scent, which suits anyone sensitive to cedar aroma. Cedar has a strong, warm characteristic scent by comparison.
Is thermowood more durable than cedar?
Thermowood is heat-treated specifically for extra dimensional stability and rot resistance, while cedar is naturally rot-resistant. Both are durable; thermowood can be slightly more brittle.
Can you mix cedar and thermowood in a sauna?
Yes — for example thermowood on exterior or moisture-exposed surfaces and cedar or another cool wood for benches. Use cool, knot-free bench wood where skin rests, and leave all sauna wood bare.
Which has a nicer colour, cedar or thermowood?
It is a matter of taste — cedar gives a warm, light tone, while thermowood gives a rich, darker one. Choose the look you prefer; both perform excellently as sauna wood.
Do cedar and thermowood need different care in a sauna?
No — both are left bare and cared for the same way: clean gently with warm water, refresh with light sanding, and never seal them with varnish. Kept bare so they can breathe, both stay durable in a sauna heat and humidity for years.
Where is thermowood best used in a sauna?
On exteriors and surfaces exposed to moisture, where its enhanced stability and rot resistance shine, and where its rich, darker tone suits the look. Many builds pair it with cedar or a cool wood for the benches.
Can you combine cedar and thermowood in one sauna?
Yes — a common approach is thermowood on the exterior or moisture-exposed areas and cedar or a cool wood like aspen for the benches. All sauna wood is left bare and cared for by light sanding.
