Saunas have a lot of health benefits. This is why more and more people want to either buy or build one for their house. Whether it is an indoor sauna or an outdoor one, picking the best wood for your sauna is definitely going to affect its performance and appearance. This is why I made this article where we will go through some of the finest woods and compare their pros and cons. We will also talk about scents, synthetic materials, and some other sauna accessories that can be made in addition to your main room.
Head over to my outdoor saunas guide to see some ready-made models which are perfect to use outside and are of great quality and craftsmanship. Before we dive deeper into the individual sorts of wood you could use in your sauna, we first need to make a clear distinction between the two major types…
Softwoods vs Hardwoods
When making a sauna, one of your first choices will have to be choosing between softwoods and hardwoods. Softwoods are derived from evergreen trees such as hemlock, cedar, pine, and others. They are easier to cut and are a common choice among sauna manufacturers. Hardwoods, on the other hand, come from deciduous trees such as basswood, eucalyptus, and poplar.
The biggest advantage softwood has over hardwood is that it is relatively cheaper and easier to work with. Whether it has better long-term properties is up for debate and you will hear conflicting opinions on that particular topic. It is also cooler to the touch when used in saunas, making it even more convenient for a hot room. Hardwoods are typically better looking if you want a light-colored sauna and they are perfect for medicinal use since they are more or less odorless and hypoallergenic compared to some softwoods.
The softwoods that are used in saunas the most are:
Hemlocks are Canadian conifer trees which are durable and are best known for their color as well as their uniform and smooth texture. Combined with modern elements such as tempered glass and LED lights, they really make for an elegant design. Hemlock is also relatively inexpensive and easy to work with. For that reason, it is used in low-cost saunas and it also has a few disadvantages which are common to the Spruce and Pinewoods as well. They are mostly thin and can warp and bend easily if not treated properly. On top of that, they are inconsistently colored most of the time which can ruin the appearance of the sauna.
The Canadian Red Cedar is one of the best woods you can use in any sauna. It is an ideal choice mainly due to its natural moisture-resistance. Cedar is also very robust and has a unique texture that some people prefer over most others. It doesn’t contract nor does it expand in fluctuating sauna temperatures and humidity and has an authentic scent to it which adds to the comfort of the sauna.
Pine is really similar to the Spruce and Hemlock woods in terms of its color and consistency. Unlike them, however, it has more knots, evaluating its price a bit compared to the rest. What makes it unique is that it gives out a pine scent when heated up inside the sauna. Still, having these knots fall off your walls is a great disadvantage that some people simply don’t want to deal with.
Firwood has been used in traditional saunas for quite some time now. It is rich in knots which adds to its authentic look but also leaves the possibility for them to fall off if not treated properly. It has a light-brown color and is easily worked with. The best thing about it is that it allows wooden saunas to be made with respect to nature by sourcing it from controlled forests only and it is also grown relatively fast for this exact purpose.
The main advantage Spruce has over woods like Hemlock and Cedar is that it is cheaper. As with most other softwoods, it has a light-colored pattern paired with a fine grain. It is really common in traditional Finnish saunas.
Now, let’s take a look at the opposite spectrum of woods you can use for your sauna…
Some of the most common hardwoods used to make saunas are:
Basswood, known as Linden in Europe, is one of the most commonly used hardwoods on the market. It is a light-colored hardwood that has no fragrance and is also a fine alternative to Cedar both in terms of quality and in terms of price. It is also the cheapest type of hardwood out there.
This wood also has hypoallergenic properties making it ideal for medical facilities of people with different types of allergies. It also has a soft feel to the touch mainly due to its fine surface and fewer knots. Another one of its standout features is that it is really good at heat absorption and isn’t hot to the touch even in a fully heated up sauna. As a whole, it is one of the best mixes of good value, decent quality, and good enough sauna properties.
While eucalyptus is rarely used due to its rare nature, it is still a great choice for a sauna if you can get your hands on it. Logically, it will be extremely expensive which is one of its biggest downsides compared to other hardwoods.
It has a brown to red appearance which is characteristical to the Australian weather where it grows. Speaking of its growth, this is one of the most sustainable trees to use for such DIY projects since it grows fast and can be easily regrown.
Poplar is a light-colored hardwood which just as basswood, has almost no scent to it and is a great choice for medical establishments and spa centers. Compared to hemlock and cedar, however, Poplar is more expensive.
As a whole, hardwoods will all be hotter to the touch than softwood with Basswood making a slight exception since it absorbs heat nicely and never gets too hot to the touch no matter the ambient temperature. That is one of the reasons it is so widely used in saunas.
Taking scent into consideration
The scent is where most people clearly divide into two groups. Some people really like having a scent to their sauna as it heats up while others prefer the more neutral approach of some scentless woods. Speaking of scentless, if you want your sauna to have no scent to it, Poplar and Basswood are the kind of woods you want to use.
For the people that like a wooden scent Cedar and Hemlock is the way to go for them. They will leave a fresh wooden smell that will last for months or maybe even years in a newly built sauna. The downside to softwood having a scent that won’t go away is that if you really want to use any of them, you will have no way of dealing with the woody smell.
If you want a more authentic and pleasant scent, Pine is definitely something you should consider. There aren’t many Pine-made saunas for commercial use so it will be hard to imagine or see in person but in general, Pine is one of the best options if you want to have a fresh and forest-like scent to your sauna.
Advantages and disadvantages of synthetic materials
Whether or not to use synthetic materials in your sauna has probably crossed your mind if you’ve gone deep into your DIY project planning. The main synthetic material used in saunas is composite wood. It is made out of plastics, wood fibers, glues, and binding agents which can all cause skin irritations if they don’t fall under certain emission standards.
While composite woods are cheaper and typically easier to work with, they can be dangerous if they aren’t meeting formaldehyde emission standards for wood that can be used in furniture. Saunas aren’t the ideal environment to test out the emissions of a certain material, however, since they get quite hot and they can only make the emissions issue worse.
Other synthetic materials that you might get tempted to use in your sauna project are oils, laminates, putties, glues, other types of adhesives, and others. These will certainly help you with the construction process as they are also cheap and easy to find. However, they can emit dangerous toxins when heated to 160 degrees and exposed to high humidity. That is one of the main reasons saunas are typically built only by a handful of materials including the natural wood planks, stainless steel screws, and a few other elements.
Woods for different sauna accessories
Saunas are full of accessories often made out of wood as well. Buckets, headrests, backrests, footrests, essential oil cups and holders, are all typically wood-made. While it is a good idea to match them with your sauna’s main choice of wood, you can be free to experiment as you wish. If your sauna is made primarily out of Basswood but you want a little more scent, you can include Fir or Cedar for one of your smaller accessories for a subtle forest scent. If that scent bothers people you can simply remove the said accessory. Backrests and headrests are typically made out of softwoods which aren’t as easily stained and are much better at heat absorption. That will prevent them from being hot to the touch and actually allow them to add to your comfort.
Learn more about the sauna etiquette you need to follow when going to a spa center by clicking here!
What you need to know about Phenols
Phenols are chemical compounds that are found all around us. They occur naturally in nature, primarily in scent-rich trees and plants. They can be inhaled or absorbed through our skin and are technically (chemically-wise) toxic for us. Still, most of the naturally-occurring phenols aren’t toxic to humans and can be even found in the food that we ear. They are also used synthetically in various soaps, toothpaste, mouth wash, and other products where they have a primarily antibacterial role.
In trees like Pine and Cedar, phenols are the chemical substances that give them their distinct scent. That is great for most people but some can be overly sensitive to them. In these cases, using fragrance-free woods like Basswood or Poplar is the best option.
Frequently Asked Questions
What kind of cedar do you use in a sauna?
The most common Cedar type used in saunas is Canadian Red Cedar, more specifically Canadian Western Red Cedar. It is faster to grow that British Western Red Cedar and is, therefore, more ecologically friendly to use. This cedar type also has a pleasant scent that it emits once your sauna is heated up. It is also quite resistant to discoloration, staining, and odor absorption.
Can you use pressure-treated wood in a sauna?
Most outdoor saunas will lay on concrete fundamentals. Normal wood will most likely rot if directly in contact with that concrete so using pressure-treated wood for your sauna’s base is advisable.
Are Cedar saunas toxic to people?
Woods like Hemlock, Fir, and Red Cedar aren’t toxic to people. Still, as there are natural oils and resins in the wood, a small portion of people might experience mild allergic reactions. If you plan on making your sauna from similar woods, make sure to test yourself and see if you’re allergic to any of that.
To sum up the topic of the best wood for sauna we can put it that way – If you want something hypoallergenic, then go for basswood. Basswood is also great at heat absorption and isn’t as hot to the touch when heated up as some other wood types. In terms of durability, cedar is the clear winner. For an authentic style, you can consider eucalyptus, although it is quite rare. And lastly, for the cheapest possible alternative, you can opt for Spruce, although it won’t be as durable as some more expensive soft and hardwoods.