Let’s face it, aesthetics do matter. And nowhere more than in a sauna. But looks are only one factor in choosing a sauna wood. And we need to consider how the wood will look in a few years.
Indeed, Western Red Cedar, the most popular sauna wood in the United States changes more than any sauna wood. And not always for the better.
You have likely notices water marks from sweat, leaks, and Loyly in western red cedar saunas. That’s because it develops water marks easier than other woods, it’s its unsightly.
Some people like the darker cedar as it ages, but be aware the instagram photos you see of brand new cedar saunas don’t last.
Many people in America don’t even realize there are other choices for their sauna walls, while the rest of the world does NOT use cedar in their saunas AT ALL.
These are the best types of wood suitable for sauna walls, their unique properties, and why they matter.
Selecting the Perfect Wood For Your Sauna
#1 Common Aspen (Populus tremula)
You’ll notice the most popular sauna woods in the rest of the world were selected to give the sauna a ‘clean’ look with few knots.
Common Aspen is often the first choice for sauna interiors, thanks to its light tone, smooth texture, and very low resin.
This wood type is distinctive for its rich colorfulness and low density.
It scores 444 on the Janka Hardness test vs 350 for western red cedar. That’s still a very soft wood and won’t be too hot to sit on but it also won’t scratch quite as easy as Cedar.
Like cedar, Aspen does have a tendency to shrink significantly. That’s not a problem if accounted for during construction with proper gaps. Thermal modification is another option that makes aspen more stable that we’ll talk about later.
Aspen benches are indeed an attractive choice. Pairing aspen benches with a darker wall paneling is becoming very popular.
Aspen tends to be more expensive than other European sauna woods like Alder but it’s still less expensive that western red cedar.
Another benefit of Aspen is its durability over time. Aspen retains its original look even after five years without sanding or finishing. This makes Aspen a low-maintenance option for saunas.
Aspen can gray over time, but it accepts sauna wax very well if you’d like to preserve the original lightness.
While Aspen won’t show water lines as easily as western red cedar, it is quite susceptible to mold or mildew. We would not recommend aspen for the exterior of a sauna.
Again, Thermal modification will help. Also, the best practice of sauna construction is to leave an air gap behind the cladding using 1×4 spacers between the wall studs and the cladding. This will essentially eliminate any risk of mold or mildew in a well ventilated sauna.
In crowded commercial spaces, Aspen has proven to age better than cedar. Given the lower traffic in a residential setting, Aspen will likely maintain its appeal for longer. Regular maintenance, such as an annual sanding and sealer application, can help ensure its longevity and continued attractiveness.
In Scandinavia, Aspen is almost the standard for high-end saunas and is the preferred choice in places like Estonia. This is likely due to the wood’s many benefits, including its smooth texture, light tone, and the fact that it doesn’t secrete resin, which could otherwise cause discomfort in a sauna setting.
In summary, Aspen is a fantastic choice for sauna interiors and exteriors. Its smooth texture, light tone, non-resinous nature, and longevity make it well worth the investment. While it may require some maintenance to prevent greying and water damage, these efforts are minor compared to the benefits of this beautiful, durable wood.
Each downside of aspen in saunas can be solved by opting for thermally treated aspen (more below).
You can see regular and thermally modified aspen in action in Auroom sauna kits.
We stock sauna-grade aspen, and thermally modified aspen from Europe in the United States! This includes wall paneling, bench materials, trim, and even textured wall paneling that’s really popular right now.
Use the chat window or contact Sauna Marketplace for a quote!
#2 Alder (Alnus glutinosa)
If you want to panel your walls like the Finns do at an affordable price, definitely consider Alder.
It’s a resilient, pleasant wood with good water-repellent properties.
Whether thermally modified or used in its natural form, Alder stands out with a lovely reddish hue that enhances the visual warmth of any sauna. It can be difficult to tell alder apart from untreated Aspen to the untrained eye. Look for the reddish hue.
Alder wood is also versatile in its finish options. It can be thermally modified for improved durability and stability or used in its natural state, showcasing its innate beauty.
If going with an untreated wood without thermal modification, we recommend Alder for its water resisting properties. Splash that water on the rocks without worrying about getting it on the wall.
European Alder has a Janka score of 650 so it’s just a little harder than other sauna woods. That makes it more resistant to scratching but might start to feel a little hot to the touch. Sitting on a towel is recommended anyways.
You can buy alder sauna wood from us at SaunaMarketplace.com. We sell a variety of dimensional lumber and profiles like 1×4 tongue and groove, modern vertical step cladding, and various bench and backrest sizes. Alder is also available on several Auroom Saunas for sale here.
#3 Thermally Modified Norway Spruce (Picea abies)
When looking for a unique, durable, and visually appealing wood for your sauna that can handle the outdoors, thermally modified Norway Spruce is a standout choice. Available through Sauna Marketplace in barrel sauna kits, 1×4 T&G, and 2×4 material – it’s a favorite among customers for its many attributes.
Thermally modified Norway Spruce rustic appearance and visible knots bring a sense of natural serenity to your sauna. The wood undergoes a thermal modification process from Thermoy, which enhances its weather resistance and durability. This process also gives the wood a naturally beautiful light-golden tone, adding to its aesthetic appeal.
This type of wood is an environmentally friendly choice. It is derived from sustainable forests, with no chemicals involved in its modification process. The thermal modification provides the spruce with excellent durability (class 1), offering 25+ years of protection against wood decay. The process also significantly reduces the wood’s moisture absorption capability and rate, resulting in less moisture-induced deformation.
The Norway Spruce is light in weight, soft, and presents a nearly white color in its untreated state. It boasts medium mechanical properties and splits less easily than pine due to being less resinous. It becomes considerably more durable and stable after thermal modification while taking on a beautiful golden-brown tone.
Thermally modified Norway Spruce is an excellent choice for sauna wall cladding, providing a beautiful, durable, and environmentally friendly solution for enthusiasts. You can find this exceptional wood material in the barrel sauna kits offered by Sauna Marketplace, and customers have reported high levels of satisfaction with their purchase.
You can also contact us for 1×4 T&G or 2×4″ dimensional sauna wood.
Western Red Cedar (Thuja plicata)
Western Red Cedar is loved for its water-repellency, delightful aroma, and ability to resist overheating, making it a charming choice for sauna walls. When North Americans think of saunas, they think of this wood type and that’s not changing anytime soon.
Cedar is widely popular in the U.S. and Canada, but European countries such as Finland and Sweden rarely use it in saunas. That’s mostly because they don’t know what this North American timber is, but also due to its potent aroma. Moreover, cedar contains Thujone, which can be a neurotoxin and a potential carcinogen. Despite its charm, its usage should be considered with caution.
If you’ve been in a gym or hotel sauna, you know cedar doesn’t always age well.
Canadian Hemlock (Tsuga canadensis)
Canadian Hemlock stands out due to its durability, knot-free texture, and ability to radiate heat evenly, making it an excellent choice for sauna interiors.
Additional Options
Other choices include the Common Alder, Scots Pine, Norway Spruce, American Ash, Radiata Pine, Poplar, and Magnolia. Each offers unique properties that can suit various aspects of sauna interiors or exteriors.
Why Wood Matters: More Than Just Aesthetics
Apart from giving your sauna a great look, wood has functional benefits. It possesses hygroscopic properties, which can absorb humidity and then release heat, leading to a comfortable sauna experience. Some woods, like Abachi, have the advantage of staying cooler to the touch and absorbing noise, thus creating a peaceful ambiance.
The functionality of wood increases with height. Therefore, using more wood in the upper sections of the sauna is recommended. If you’re considering including aesthetic elements like exposed brick, try to place them in the lower portions, keeping the upper three-quarters all wood.
Tips for Installation: Board Size and T&G Construction
Regarding the board size for interior cladding, a 1” x 4” nominal size is usually considered optimal. However, you can go for wider or thinner boards, considering that they might cup in colder climates.
You can’t overlook the use of Tongue & Groove (T&G) construction. Given a sauna’s extreme temperature and moisture conditions, wood may warp. The T&G construction can help reduce this effect. If you opt for T&G, install it with the groove facing down to prevent sweat or moisture from collecting in the grooves.
“STEP” or “STP” boards are increasingly popular. They have groves and channels and are typically installed vertically in the sauna room.
It can have a strong effect when paired with other textures, species and profiles. Let’s get creative!
Gone are the days of boring western red cedar horizontal tongue and groove. Contact us for a full catalog of sauna wood types available in dimensional lumber, prebuilt saunas, sauna kits, and from custom builders. Let’s have some fun with this, and make it your own!
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