I thought I was building and advising people to build saunas correctly. And for the most part, I am. However, there is one WIDE difference on what many are doing in the US compared to Finland: a gap along the hot room door.
Finns- the pros- are nuts about fresh air and venting. With a wood fired sauna stove, this is critical, yet not as critical as with an electric stove.
Why? Wood stoves draw air and help circulate air on their own. But electric stoves suck, in terms of air flow and ventilation. We need to be cognizant of good venting.
Why? Fresh air and oxygen circulation allow us to enjoy our time in the hot room. Dizziness from time spent in a sauna is more apt to be from a lack of oxygen than too much heat. How do I know this to be true? I took 50 saunas in 12 days in Finland, and I was never dizzy.
- 43-44″ (109cm) Top bench to ceiling. When sitting on the upper bench, we want to be able to put two fists over the top of our head to the ceiling.
- 16-18″ (46cm) lower bench. This is optimal chair height and comfortable for most adults (no scrunching or feet dangling).
- 6″ (15cm) raised floor deck. This step up, when entering the hot room, keeps the feet warm when sitting on the lower bench as we have an air gap from the actual hot room floor to where you sit, stand, or walk.
- 4″ (10cm) gap along hot room door. This makes the Finns happy. Plenty of air flow.
- Vent: opposite wall as stove, eye height while standing. A few inches (10cm) down from the ceiling.
I have tuned my 7′ tall sauna hot room bench heights as follows, and approve this message:
- 44” ceiling to top bench.
- 16” to low bench.
- 16” to step or raised floor.
- 5” step to duckboard, height of changing room.
I know, I know, while sitting on the upper bench, our feet, resting on the lower bench, are a few inches below the sauna rocks.
If we build saunas with 7’6″ (229cm), we can move everything up 6″ (15cm). This way, while sitting on the upper bench, our feet are at or above the sauna rocks. But this creates a new problem. Now we have 12″ step up from changing room floor to hot room floor. Two steps, 6″ (15cm) each can be quite clunky and cumbersome. Worse, these steps can be dangerous for children or senior adults as they navigate themselves off from the top bench, down steps and out to the lake or cold plunge water feature.
While sitting on the upper bench, do we want our feet a few inches below the sauna rocks, or do we want 12″ of up and down steps each time we enter and exit our sauna hot rooms? Many (including me) choose to have feet a bit below the sauna rocks and one less step coming and going, over and over.
Thanks to Miller for forwarding this photo, sourced from finlandia sauna. Indeed, this photo is worth a thousand words. 8′ ceilings MAY have their place with a triple bench system, in health clubs and spas, yet even this is a stretch. There are too many wasted cubic feet to heat.
The good news is if you have 8′ walls in your ceiling, consider dropping down the ceiling. It can be done!
When designing and building our own saunas, hot room ceiling height is a key decision. Sauna bench height is defined and constrained by our hot room ceiling height.
Whether we choose an 8′ ceiling (244 cm) or a 7′ ceiling (213 cm) , or some height in between, our first definition is:
This upper bench height is a critical measurement as it allows for 2 fists above your head to the ceiling, as we sit on the upper bench. This gives us access to the best heat, “without leaving anything on the table.” (Mike Norsdog, Opposite of Cold). Further, this bench height allows for air flow around our head, where it matters most.
Empirically minded sauna builders have been known to walk around with tape measures charting the height of their couches, dining room chairs, desk chairs and even park benches (when nobody’s watching). Consensus on this measurement (mean, median, mode) is about 18″ (46 cm). So, generally we adopt this measurement for the height from upper bench to middle bench. There is wiggle room here. Examples where one may consider, say, 16″ space between upper and middle bench may be where the most use case is with folks who are less tall than the average bear, eg. shorter significant others, a lot of kid use, etc. A 16″ space between upper and middle bench reduces feet dangling, and creates a gentle flow up, climbing up and down.
Finns are generally very accepting people, especially as it relates to sauna. There is a “free spirit” of few rules with Finnish sauna. Dogma in this case is more a combined word of a common house pet and what Italian Americans often call their mothers. Simply put, the law of löyly means that as you sit on the upper bench, your feet are at or above the height of your sauna rocks. To a Finn, the law of löyly could be as important as beating Sweden in the World Junior hockey tournament. Outspoken sauna aficionados from the Motherland of sauna are easily riled with the idea of sitting on the upper bench and having one’s feet below the sauna rocks.
Not all sauna stove heights are created equal. I am a big fan of the Kuuma sauna stove. This stove sits proudly off the floor 34″ tall (86 cm), (32″ for the stove, 2″~ for a base). Saving you the math, a 7′ ceiling means a trip to the penalty box for breaching the law of löyly. Shorter, more stout sauna stoves can help a 7′ ceiling meet the law of löyly, but not the Kuuma stove. For a new build, we can push our ceiling up to 7’6″ (229 cm) or even 8′ (244 cm), and we are playing 5 on 5 hockey with no frowns from the Finns. Sitting on the upper bench, can our feet now meet the height of our sauna rocks?
The height from the middle bench to the floor, with a 7’6″ tall hot room, is 28″ (71 cm). (MATH: 90″ – 44″ – 18″ = 28″). Geez, now what? Well, we can set our “3rd bench” 18″ down from our middle bench, and that leaves us with a clunky 10″ (25 cm) drop from the 3rd bench to the floor of our hot room. In this instance, a 10″ raised floor from changing room may be a greater evil than the penalty box. We’re talking a trip to the locker room for a busted head from a fall navigating from the mega step up from grade, up to the 3rd bench, up to the 2nd bench and settling our butt down on the upper bench. And after all this climbing, even with this configuration, our feet would be a good 8″ below the rocks, while sitting on the upper bench.
As we consider the height of our hot room ceiling, meeting the law of löyly for a 34″ tall sauna stove requires us to build our hot rooms with 8′ tall ceilings. (244 cm). Breaking this verticality down into manageable steps and benches require 5 levels of maneuvering.
- Upper bench (44″ from ceiling)
- Middle bench (18″ from upper bench)
- Lower bench (18″ from middle bench)
- Raised floor (8″ from lower bench)
- Step (8″ from raised floor).
All these levels are dizzying. Add wet feet, a little lightheadedness, a bucket of löyly water, and a grumpy Uncle yelling “close the door!” and you’ve got yourself navigating the Bleacher Effect. Remember in high school making your way up the bleachers and feeling the eyes of every other student on you? That’s the Bleacher Effect in action. Plus we have that extra 1′ of cubic volume of hot room to heat.
We want our saunas to be comfortable. We come and go into our saunas a few times each sauna session. Climbing bleachers get ourselves away from the flow of good sauna. So, we need to balance the law of löyly with the Bleacher Effect.
Saunas in the public domain have a larger footprint than our home, backyard saunas. Larger saunas can afford the space for lots of steps. As example Rajaportti Sauna in Tampere has several steps up to the “2nd level.” Kaupinoja sauna has several benches flanked on both sides very similar to stadium bleachers. Lonna Sauna in Helsinki has a landing, half way up the stairs, which offers access to toss water on the rocks. These public saunas work as the footprint is generous enough to bring the sauna bather up, up, and above the sauna stove rocks.
So, as we consider the height of our own backyard saunas or indoor saunas, we have to balance the law of löyly vs. the Bleacher Effect. An easy work around for our private saunas with lower ceilings is to simply settle ourselves onto the upper bench, then bring our feet up onto the upper bench, thereby our entire body is above the sauna rocks. This could be American ingenuity or German engineering. Whichever the case, we respect the law of löyly, but we don’t want to fall on our ass getting there.