Here you can read about my musings on the sauna experience and the sauna design and building process. Some of the information will be practical, some will be wispy and esoteric like the steam of the löyly rising from the hot rocks. Happy sauna-ing!
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One issue that comes up frequently when building anything, including a sauna is Code. In builder’s parlance code refers to the building code or International Building Code (IBC) which is broken down into specialties such as National Electrical Code (NEC) Residential Code, Commercial Code, Mechanical Code, and so on. Each one of these rule books fills a tome about as thick as a two-by-four; the whole set requires a dedicated book shelf and years of study to understand fully. Mostly there is national uniformity but some states have specific additions to the Code. A peeve of mine is that even though his set of prescriptive building measures constitute laws that we are mandated to follow, to access them completely, you need to pay a third party, the International Code Council, hundreds of dollars, or more, a year in subscription fees (go to: iccsafe.org). That, by itself, sets up the animus relationship builders tend to have towards them.
Saunas are a special category of construction, both for residential and commercial situations. They have unique needs and functionality and are poorly understood by those not in on the magical powers we aficionados know to be true. The rules are subject to the interpretation of bureaucrats who have the power to force changes or even shut down operations.
Often, when it comes to sauna, they are mis-informed by myth and superstition. I have gotten the sideways glance that tells me they think saunas are in line with brothels and other dark intentions, or that sitting in a 200 degree room is insane and will “cause your skin to melt”. I had one inspector, citing his fireman training, trying to convince me that throwing water on a sauna stove would cause it to explode and that the wood fired sauna needed some mechanical means to dump all of the hot air if it reached 90° C. (The owner, an engineer with a sense of humor and money to burn, designed an an enormous automated fan to dump the heat, that worked once: for the inspection.)
Other inspectors have asked where the water tub was (no, that’s a spa) or gave me clues they had no idea what they were looking at. One wanted a safety call button installed in the sauna.
Not all are bad: some have been enthusiastic, launching into their own childhood sauna tales, or dreams of owning one. These are the inspectors you want to work with. Unfortunately, you don’t get a choice; each jurisdiction has it own inspector: the Authority Having Jurisdiction or AHJ, who, ultimately is the one making the decisions regarding your project, despite what is written in the Code Book. If the Code Book is the bible we must obey, then that makes the inspectors a kind of God who can supersede it; add in a huge ego or overzealousness and the situation becomes untenable.
So, like dealing with God, you want to develop a positive relationship with your inspector so that when you have to call on them they will be your ally. During a scheduled inspection, it seems to me that they are inspecting me: if the job site appears neat and organized, my truck is nice, and I don’t ask a lot of dumb questions, then the work must be good. The truth is, there are so many small details like nail size, type, or spacing (found in the fastener schedule) that there is no way to scrutinize every detail, so best to assume all is well if the builder seems to know what they are doing. The exception is the Electrical Inspector- who, in my experience, has a much more serious job to do; the 240 volts that supply sauna heaters can be deadly in an instant and presents hazards unseen to users. Rarely do I meet them onsite, they work clandestinely and leave their approval stickers on the electrical panel box. I want the inspector to work undistracted. If you are DIYer and getting an electrical inspection, you’ll need all your t’s crossed and i’s dotted to pass. Messy wiring might still work, but it may fail If it is hard to follow the wires visually; there can be no hidden mistakes. Mostly I use licensed electricians who you can tell are good just by the way they dress: shirts tucked in, matching socks and pants pulled up.
In all of that 2 feet stack of code books, I could find the word “sauna” only 16 times, which means there is very scant instruction for both the builder and AHJ to follow.
The exception to following code is when the appliance (sauna heater) has instructions that may counter the rules or make more specific instruction. So, except for a few situations, we can rely on these manuals for not just guidance but as a fallback for when the inspector comes (you should include a copy of all manuals when you apply for a permit). In many cases the manuals are written in several languages for the European market—a fault of the European companies who supply most of the heaters available here. This turns what should be a 10 page manual into a 60 pages of mostly gibberish for American contractors. Who has time to to convert metric to English?
America is such a huge market, manuals should be edited specifically for our market— not just crudely translated but re-written to conform to our our trade practices. If the inspector has questions, be ready with those details highlighted in the manual!
There is a drawback to the manuals: the required UL (Underwriters Laboratory) listing that the heater has (currently UL875) applies to the heater as installed per the manual. So, it is not just a guide, but a definitive set of rules that you must follow in order to make UL listing valid, and thus to pass inspection. These rules can supersede the Code and follow current established guidelines. Currently UL 875 says sauna heaters installed in the US must have a device to limit the room temperature to 90° C (194°F) measured by a thermo-sensor 6” from the ceiling. The Code follows suit with the same rule. We all know that temperature is very stratified in a sauna— as much as 10°F per foot, so 194° near the ceiling will mean 154° at the top of the upper bench, which is tepid at best, to most of us. I want at least 194° where my head is, so I lower the sensor on the wall, (if you call Harvia, they will tell you to do so). So, the only way to get a decent heat in the sauna is to break the rules and Harvia agrees! (This is also a good time to point out that having the ceiling 6 “ above your head is ideal if you want your sauna hot at head level, which makes cathedral and other high ceilings pointless.) But even after moving the sensor you will hit another US UL imposed roadblock to high heat heaven: the heaters all have an internal high limit sensor set lower than their Euro cousins so that the heater body doesn’t get too hot- because God knows, we don’t want anyone burning themselves or catching things on fire, like a towel left to dry on the rocks ( the assumption is that common sense does not exist here in the US—which, looking around at things like helmetless electric scooter riders, I can understand).
But now we have a window of reprieve from all of this confusion and an acknowledgement that that some people do like it hot (and have a right to enjoy it without guilt): a new UL standard: UL 60335-2-53.
This standard allows heaters to heat saunas to 125°C and for the sensors to be placed at head level over the bench and allow the internal high limit control to be set higher. All of this was possible before by tinkering with the installation but now, in theory, we can have this new manual to back up common sense. And, it will be legal, which means my contractors liability company will back me up if things go awry.
This is great, in theory. Code defers to the manuals but the problem now is that the manufacturers have to re-write the manuals and present them with their heaters to be tested by UL and pay for this new level of certification. They are moving slowly- too slowly, perhaps because they need burn through existing inventory, or perhaps, they don’t think Americans are ready for European hotness. But we are and have been.
My wood burners get well over 100° C and people enjoy it. They tell me they have never experienced sauna like that, that it’s life-transforming. I want that possibility to be available everyone: the basement electric sauna people, and the people who feel guilty burning wood, or don’t have the yard for wood burning.
When the manufacturers move forward with by updating their heaters to the new UL, the book of Code will have to follow, and it will be declared that sauna can be hot. And then, even the suspicious bureaucrats will begin to understand and sauna inspections will fall in line with other inspections and we won’t have to hide our saunas or work under the cover of darkness. I don’t hate code, but hate how trying to work with the permitting process gives me the blues.
P.S. We build a lot of mobile saunas now, because, technically, they are a specialty trailer they do not fall under the purview of any building department. As long as they remain mobile and have a license plate there is little say most municipalities have over them.
Recently, you may have read the news about the fire at Driftwood Public Sauna in Milwaukee. Fire caused a total loss of the newly built facility, which looks to be a building on a trailer parked near the waterfront.
My sympathies to the owner, Derek Collins, and his team who clearly put their heart and soul into this project, which looked beautiful in the before images. As a small business owner, this is a worst nightmare scenario. Even with good insurance, recovery will be difficult (there is go-fund me page).
But let’s not all go running away from wood fired saunas with this image glued to our minds. Woodburning sauna stoves installed correctly are not dangerous.
Sure, the old Finns would build their saunas away from the house because, well, sauna fires do happen, and even the old sauna at Podunk clearly toed that line many times, evidenced by the seriously charred wood we found when we deconstructed it. But modern stoves and the associated chimneys are engineered and tested to heat a sauna. They are not cobbled together like the way the pragmatic old Finns did things, fabricating as much as they could from scrap metal. And neither should you be cobbling things together and taking safety shortcuts.
The fire is “under investigation”. Looking closely at the image of the fire, I know exactly what caused it. Fire rises; the lowest charred point is the point of origin.
I know that stove: the Harvia Legend Duo 300. It is meant to be fired from the outside— which is perfect for a public sauna where the fire tender has to do their job while staying invisible. According to the instructions, It is meant to be fired through a masonry firewall (see above instructions) with a minimum of 12“ of masonry one each side, yet in the photo of the fire I see plywood right next to the stove. I don’t want say it, but WTF?
On the inside there is (was) a tiled fire shield with what looks like the appropriate 1” air gap behind the stove extending to the ceiling. This looks nice, but a fire shield is not a firewall. A Firewall is entirely non-combustible, a shield simply protects a wooden surface behind it.
The plywood clearly got too hot (remember Ray Bradbury’s Farenheit 451: the temperature wood and paper combusts!) A hot stove will reach well over 1000°F on it’s surface, and so will anything touching it. I’ll actually let mine get to a dull cherry glow on top (that’s 1300°F) just to test my installations.
I go to job sites where there other contractors working, sometimes on my designs, and I commonly see manuals tossed in the trash and my written instructions totally disregarded.
I know reading is hard ( and harder when you turn fifty and need cheaters to read anything), but, sometimes the obvious is right in front of you: you just have to read it. I cringe when I see online images of woodstoves installed too close to combustibles. It’s not like speed limits—10 inches means 10 inches. And the sauna elf will enforce that!
Wood fired saunas can be dangerous—but so can anything installed improperly. Me, I’d rather run from a burning sauna naked then get zapped with 240 volts while barefoot. Let’s keep building wood-fired saunas, but safely.
These days there is a lot of internet banter about obtaining “perfection” when building a sauna and often dogmatic rules pertaining to bench heights, ventilation, wood selection and so on. I also see frequent reference to a quote that says the only good sauna is a Finnish (made in Finland) sauna and that all saunas made in the US are bad or worse. Mostly I to try ignore it all and stay focused on continuing to build quality saunas.
This week we are taking a break from all of it by doing a Nordic ski Vacation at Lapland Lake—a wonderful family oriented Nordic skiing center in the lower Adirondacks where incredible amounts of snow are still on the ground in March. The center was built by Olavi Hirvonen, a Canadian born Finn who was raised by his grandparents back in Finland then came back to the US, eventually skiing (cross country) in the 1960 Olympics before continuing on as a carpenter near New York City. A family tragedy made him re-evaluate his life goals and led him north to Lapland Lake where he bought a chunk of the forest, built a lodge and guest cottages, and developed some of the finest Nordic ski trails in the Northeast.
Everything here bears of the mark of a Finnish carpenter, much of it reminiscent of Podunk, which was also built by a Finn. The simple construction, low ceilings, unique trim detailing, and pragmatic design prevail. When you come upon the lodge after driving miles on rough forested road the unfamiliar will be taken aback by the lack ostentatiousness. This is not built in the tradition of the great Adirondack camps, such as Sagamore.
The Finnish flag flying out front (next to the American, Swedish, and Norwegian flag) is the most obvious clue that you are here.
The lodge is an oddly proportioned structure with an asymmetrical gable roof and randomly placed windows. This is snow country where the snow often reaches the second story of houses; things are built to survive that and roof lines often extend to cover adjoining walkways or combine buildings into one. It also an economically depressed area; people make do. I’m sure when Olavi settled here, his carpenter’s salary did not leave him with piles of money to spend on fancy embellishments.
His dream and his Sisu were his capital and hard work went into everything. It is obvious, from the level of upkeep, and signs of industriousness, that the current owners continue that ethic.
Inside, the main lodge is homey and comfortable, a modest main room with a fireplace to relax after skiing, a very well stocked ski shop, an upstairs cafeteria, and a sauna down in the back. It is here that I want to focus my thoughts. At first glance the sauna is a rough affair- it has an ample dressing room with a simple phone booth-style fiberglass shower. The ceilings throughout are low, under 8 feet, and the detailing is plain. But it is clean and welcoming. Classic 1980 sauna etiquette cartoons are on the wall as well as the typical signage about adding more wood to the fire and other house rules. The bench lid lifts to reveal a firewood storage; a classic sauna detail.
The hot room door is a heavy wooden affair with a rustic stick hardware pulls. Inside the sauna is about 10 x7 feet with the wood stove ( and a defunct auxiliary electric heater) at one end with a cement block chimney behind the stove. The stove (or Kiuas) is the familiar Helo, same as the Narvia Kota Kuru, similar to the Harvia M3. This is a basic Finnish model wood burner that has been in production for almost half a century. The walls and ceiling are rough #3 cedar, commonly used for fencing, but there is a smooth back rest to lean against. The benches are pine 2 x 6’s, smoothed (butt worn!) by years of use. Heavy rust stains indicate that no stainless steel was used but the benches seem pretty solid. The whole room has that darkened patina of a well used sauna. One could say the style, if any style at all, is dated, but that is not the point, it was clearly pragmatic in design and probably the first thing Olavi built. The rooms suit their purpose today as well as they did 48 years ago. Most importantly, it is kept clean, is able to get hot, and produce a nice löyly; which is more than I can say for many, many, saunas I have experienced. When I peeked back in the following morning, the floor had been rinsed and the duckboards were propped up to dry—always a good sign.
At the end of a day spent skiing spring conditions on perfectly groomed trails, the sauna was as perfect as I could have wanted it to be. It was hot (200° F plus) and ready for me. I did a few rounds of heat and löyly followed by rolls in the snow.
I did the ritual solo but Scarlet had the pleasant company of a new sauna friend during her rounds. There is nothing I would take away or add to it. This was built by a Finnish carpenter, raised in Finland, who had more Sisu than most—how can I even begin to judge that?
The conundrum I face as a builder of Finnish style saunas, is that I would never build a sauna like Olavi did. I know too much now. My purpose now is not to just serve that basic need of a hot sauna at the end of a hard days work or play, but to serve the increasingly diverse needs of a range of clients. Because one client will demand “perfection”, the bar is raised on all of my work. It would be criminal if we did not use the best available materials and accepted building practices. The competitive demands of the web require that each build be not only perfectly functional but photogenic as well. And the economic demands of running a business and supporting ourselves require that we have to balance making a decent profit with making quality products. We achieve that by marketing to a higher level clientele rather than cutting corners—but those higher expectations of what quality looks like and what it costs, cuts out the poorer customers, the common folk, whom we still want to bring sauna to.
Olavi built his dream resort before the web existed and before the current sauna revival. He depended on word of mouth and yet had a steady stream of returning customers and sauna devotees who continue to enjoy the simple pleasures of this modest haven.
Built on a budget, maintained for years on a shoestring and resourcefulness, and driven by his Sisu, or perseverance, Olavi achieved a level of quality that may now be lost to the frenzy of our internet driven times.
Note: Olavi Hirvonen died in the fall of 2024 at the age of 93. The new owners, Kathy and Paul Zahray, are committed to continuing the traditions at Lapland, including keeping the sauna hot!
