Sauna Wood Species Compared
Which wood for benches, which for walls, and which to keep out entirely, by how it conducts heat, whether it carries resin, and what it costs.
| Species | Heat to touch | Resin | Rot resistance | Scent | Price | Best use |
|---|---|---|---|---|---|---|
| Western Red Cedar | Low | None | Excellent | Strong, aromatic | $$$ | Benches & interior, the classic |
| Nordic Spruce | Low–med | Low (some pockets) | Good | Mild, fresh | $$ | Walls & value builds |
| Hemlock | Low | Resin-free | Moderate | Almost none | $$ | Scent-sensitive users |
| Aspen | Low | None | Moderate | Odorless | $$ | Benches for allergy-prone |
| Basswood | Low | None | Moderate | Odorless, hypoallergenic | $$ | Benches, backrests |
| Thermo-wood (modified) | Low | Driven off in treatment | Excellent | Subtle, toasty | $$$ | Outdoor & humid rooms |
| Eucalyptus | Medium | Low | Good | Mild | $$ | Budget benches |
| Pine (untreated) | Higher | High, pitch pockets | Poor–moderate | Piney, can weep | $ | Framing only, not benches |
How to choose
Two things matter for anything you sit on: low heat conductivity so the surface stays comfortable, and no resin so nothing weeps hot sap. That rules pine out for benches and points you at cedar, hemlock, aspen or basswood. For walls the bar is lower, spruce is the workhorse.
Building outdoors or somewhere humid? Thermally modified wood has had its moisture and sugars baked out, so it barely moves and resists rot, worth the premium where a standard board would cup or grey.
Whatever the species, the wood never gets a finish on the inside: sealers trap heat and off-gas. Keep the vapor barrier behind the cladding and let the wood breathe.
FAQ
What is the best wood for a sauna?
For benches, a low-conductivity, resin-free wood you touch without burning: Western Red Cedar is the classic, with hemlock, aspen and basswood as odorless alternatives. Thermo-modified wood is the most stable for outdoor or high-humidity rooms.
Why can’t you use pine for sauna benches?
Softwood pine carries resin (pitch) pockets that heat up and weep sticky, hot sap, unpleasant and a burn risk on a bench. Pine is fine for framing behind the vapor barrier, not for surfaces you sit on.
Does the wood affect how hot the sauna feels?
Not the air temperature, but the surface temperature you touch. Low-conductivity woods (cedar, aspen, basswood) stay cooler to the skin at the same air temp, so benches feel comfortable rather than scalding.