More important than the type of wood, knowing if it was grown in the forrest or on a farm with artificial fertilizers. Wood grown with fertilizers grow 3 times as fast and do not have the chance to soak up the minerals from the ground like the forrest trees. The woods from Canada where forests are abundant have the woods for saunas that are grown in nature. They are a much harder wood than the brittle kind that splinters and warps.
When I asked fence companies, they said that the fertilized wood should last a long time but they have a good 8 year life span before they show signs of splintering and warping. The Canadian natural wood should last 60 to 80 years. Wood from the 1920s before they started adding fertilizers had the 60 to 80 years expectancy. The weakest of the woods for saunas have the shortest lifespan in the ground and the highest fertilizers.
Canadian wood is the best you can get. I have no problem with wood from China as long as you know what to expect from it.
The thickness is also important. The least amount of cracks get reported from the thicker woods. Splintering really has to do with the quality of the wood, not the thickness. Look for the mm of the wood. Some are 12mm and some can go higher, 16mm thick woods.
Also the woods should be 100% wood with no fillers sandwiched between. Trees that have grown in the forrest that are almost perfect wood without flaws are very expensive wood. I know within seconds of going into an infrared sauna if the wood is bunk. I go to trade shows and I see these off brand no name saunas and sure enough, I can always tell if its a good sauna. Many mark them up to really high prices even with the fertilized wood. Canadian lumber is very expensive.
Notice: Always asks if the wood is under warranty if it splinters or cracks.
The main choices are are Cedar, Hemlock, and Basswood. Basswood is the most expensive of all, cedar is next. Some saunas are lightweight, others are heavy and use about 20 to 30% more wood but look the same.
Caution: I always ask to get saunas with "center cut" wood. This is the Prime grade wood. Cheaper saunas might have the same wood but its usually not center cut wood. Center cut wood costs much more. If I do get center cut, I make sure it was grown in the forrest and not farm raised.
Note: The wood that is used will expand and contract as the sauna temperatures rise and fall and this is repeated for years. Over time wood thats not Grade A center cut or doesn’t have the capacity to expand and contract with ease, can potentially start to splinter or creak or crack especially when all the toxic oils excreted during peoples sweat sessions.
The way the wood is cut, how the grain of the wood is laid out is just as important as if its a center or outer cut. They can cut the wood so that the grain of the wood is laid out so it adds strength to the wood even though the wood is pretty bunk to start with.
LOOK: I always look to see if the growth rings are parallel to the load where I am gonna be sitting. Some saunas have the growth rings that are perpendicular to the weight load of the seat.
I also inspect my sauna for sloping grains. This is the big thing that can weaken the bench.
SCAM WATCH!!!!!!!!!!!!!!!!!!!!!!!!The most popular woods used in saunas:
Spruce: This has the highest strength of all to its weight ratio. This is my favorite for if the sauna is gonna be outdoors and exposed to the elements. Spruce is one of the more expensive woods to build saunas with and the grade A center cut spruce wood is way more expensive than the b grade spruce. This is one of the reasons that its hard to find saunas with grade a spruce and why most sauna companies today use mainly Hemlock, Cedar and Aspen because its readily available and its at a much lower cost.
Western Red Cedar
If I am putting the sauna outdoors then Cedar is the most durable wood I've found to be resistant to mold and cracking that can happen with lots of rain, humidness, and summer sun.
Looking at the Wood Industry Reports I found studies showing that the workers who were in manufacturing places cutting the wood, about 40% of them developed some kinda lung cancer after several years due to natural insecticides and saps in the tree. I know that airborne Cedar dust isn't really a problem when sitting in an infrared sauna but if I had a severely compromised immune system or chemical sensitivity or allergies, Cedar might not be the best choice if my skin is gonna be exposed to the wood and its being irradiated by infrared passing through the wood. It think it would be fair to say that about 2% of people cant even sit in a Cedar sauna because of their immune system.
White Aspen wood saunas have a distinct lighter look than the Western Red Cedar saunas. Aspen sauna wood is the material of choice for hospital saunas in Finland as it is non-allergenic (almost no scent). Its a good choice for
saunas that don't wanna have the over powering cedar scent that can irritate certain respiratory conditions. The best Aspen Ive found, comes from the beautiful forests of Finland. Grade A cut often looks Light, faint grain and virtually knot-free.
Caution: Beware the DIY store paneling (used in cabinet industry)! A lot of it struggles to survive in a warm living-room, let alone in Sauna temperatures... (up to 4 times higher!)
Many saunas manufactured in Japan or China will buy their wood from Canada like everyone else but purchase Grade A wood veneers (what is used for high end cabinets). These veneers are then glued onto particle board or plywood to give them the illusion of a solid more expensive construction. Particle board is made from wood fibers and chips from many different kinds of woods (that many people could be allergic to) and those chips are compressed and held together with chemicals that hold it together. This makes for a very quick manufacturing process (save on labor costs and tons of time), cheap cost of building materials, and light weight of construction (cheaper shipping costs to the manufacturer). Using all these adhesives, binders, etc. infrared rays can pass right on through and off gas the chemicals into my sauna and home. I HATE being deceived! It’s like having a Lamborghini outer shell body with a Toyota engine and mechanical components. And then the consumer pays Lamborghini prices for what is in reality Toyota quality construction. Not that I’m knocking Toyota cause I actually drive one.
See my new page on buying the right type of wood for a sauna. Go to new wood page here and learn more buying tips for choosing the right wood. click here
Man spraying pesticides on tree.
I always want to know if if the wood I am getting is farm raised or from the forrest.
Get discounts for taking the quiz before you call. Please call after 15 minutes after you take the quiz. Please refer to my rules of my site on my home page before you call and I will offer my standard discounted pricing. I will not discount saunas for those that do not follow my rules. My discounts that I have the privelege to offer are only available for those that take my quiz first and call 15 minutes afterwards.