In recent years, North Americans have taken a growing interest in the health benefits of saunas — but many are unknowingly missing out on the full experience. A true Finnish sauna is more than a hot room. It’s a carefully balanced environment designed over centuries to optimize relaxation, heat therapy, and mental clarity. Unfortunately, most North American saunas fall short due to design shortcuts, lack of translated information, or commercial compromises. This post explores what makes a sauna authentically Finnish — and why that matters.
If you’re searching for the real sauna experience, the kind backed by generations of tradition and scientific study, then understanding what makes a true Finnish sauna is essential. The difference isn’t just cultural; it’s physical, functional, and deeply tied to the health and wellness benefits saunas are known for.
🇫🇮 Finland: Where Sauna Was Perfected
Finland has the longest and most studied sauna tradition in the world. The word sauna itself is Finnish, and in Finland, saunas are treated not as luxury novelties, but as cultural essentials, as natural as taking a shower. In fact most homes are built with saunas just like homes are built with bathrooms and showers.
Importantly, almost all modern medical research into sauna health benefits comes from studies conducted on Finnish saunas, which differ in design from the common North American sauna. If you want those benefits (stress relief, cardiovascular health, muscle recovery, and deep relaxation), your sauna should at least replicate the environment studied in Finland.
Key Design Principles of a Finnish Sauna
Here are the most essential characteristics that make a Finnish Sauna. These are often ignored here in North America:
1. Bench Heights: Get Your Feet Above the Stones
In a proper Finnish sauna, your entire body—especially your feet—should be above the height of the sauna heater's stones.
Why?
- Heat rises. The warmest, most balanced air is found above the rocks.
- When your feet are below the heater, your head gets hot while your feet stay cold—an unpleasant and ineffective experience.
- Finnish saunas typically use a 3-tier bench system: the upper bench (main seating), a foot bench, and a lower step (or steps). This lets bathers fully immerse themselves in the hottest, most oxygen-rich part of the sauna.
By contrast, many North American saunas only use one or two levels, leaving your legs and feet below the heater line, resulting in poor heat distribution and discomfort.
2. Ceiling Height: Let the Heat Layer Form
A proper Finnish sauna has a ceiling high enough to allow proper stratification of heat.
- The ideal ceiling height is often between 8 to 8.5 feet, depending on the bench layout.
- This allows room for all three bench levels and the heat layer to build naturally.
Unfortunately, many commercial saunas in North America are built with ceiling heights of only 6.5 or 7 feet. While this makes them easier and cheaper to build, it crushes the heat layer, limits bench layout options, and leads to high CO₂ levels and stuffy air.
The hottest air will always rise to the top of a space. So a shorter ceiling always compresses the heat gradient, while a taller ceiling stretches the gradient and creates more even head to toe temps.
A short sauna ceiling is kind of like being dipped in a hot tub with only your head and shoulders. Its a much nicer experience to have your full body heated. Not to mention this is likely to activate more heat shock proteins (HSPs) and promote a stronger whole-body heat stress response — which is what stimulates HSP production.
In Contrast, with your typical low ceiling sauna (uneven head to toe temps):
- our body experiences partial heat stress, not full-body.
- You may even experience thermal discomfort or dizziness due to temperature gradients, potentially shortening your session.
3. Ventilation: Mechanical Flow for Electric Heaters
In a modern Finnish-style sauna with an electric heater, proper ventilation isn’t just helpful—it’s essential.
One of the most misunderstood — but vital — components of sauna health and comfort is ventilation. According to Trumpkin’s Notes on Building a Sauna:
“Wood-burning saunas are naturally ventilated, since they pull in combustion air and exhaust it through the chimney. This means fresh air is constantly moving through the space. But electric heaters don’t have this effect. If there’s no mechanical ventilation, CO₂ builds up fast — especially with multiple people inside.”
High CO₂ levels make people feel drowsy, irritable, and even nauseous — often mistaken for "too much heat." In reality, it’s not the heat, it’s a lack of fresh oxygen. This is why proper Finnish sauna design incorporates mechanical ventilation for electric units. Ensuring bathers get the oxygen-rich environment that makes a true löyly possible.
Trumpkin, via his detailed notes on localmile.org, makes a clear case:
- Natural ventilation does not work well in electrically heated saunas. It leads to excessive stratification, high CO₂ levels, poor steam quality, and diminished comfort.
- Instead, Trumpkin recommends mechanical downdraft ventilation to simulate the natural chimney draw effect of wood-burning stoves.
A proper ventilation setup includes:
- A fresh air supply vent above the heater, typically in the ceiling or high on the wall.
- A mechanical exhaust fan located near or below the foot bench level.
This pulls warm, oxygen-rich air across the bather’s body, removes exhaled CO₂, and preserves the integrity of the löyly (the enveloping steam).
“The objective is to remove stale air while maintaining the löyly cavity around the bather.”
— Trumpkin, localmile.org
Without mechanical ventilation, bathers often experience stuffy, oxygen-depleted air and leave the sauna early—not from too much heat, but from CO₂ buildup and discomfort.
Trumpkin also notes that many manufacturers have encouraged incorrect vent placement (such as fresh air vents below the heater) to protect overheat sensors, not to improve the sauna experience.
“Almost all U.S. manufacturers suggest supply below the heater and exhaust up high. These are not for your benefit. They're for UL sensor compliance.”
— Trumpkin, localmile.org
4. Big Enough Room Size
Well it may seem intuitive that a sauna doesn't need to be big, especially if only being used by 1 or 2 people. It is actually more complex than just needing a space that gets "hot" quick.
The beauty of sauna is the gentle heat you experience, as heat rises from often 100+ pounds of sauna stones, then slowly travels over to you on the benches. This gentle heat is known as convective heat, and it relies on having enough room for the heat to move and form a natural circulation, or convective loop, within the sauna.
In very small saunas, or compact barrel-style designs, you’re often sitting too close to the heater. This means you feel mostly radiant heat—the intense, direct heat similar to holding your hands near a campfire. While this can be warming, at sauna temperatures it often feels harsh and uncomfortable on the skin. When water is poured onto the hot stones, the resulting steam hits you abruptly, which can be jarring rather than soothing.
In contrast, a properly sized sauna allows the steam to slowly travel from the heater across the ceiling, and gently fall down your body from head to toe. This process can be repeated over and over again, and is one of the most glorious feelings in a sauna. In too small of a sauna, you can simply never get this experience, even if you only need space for 1 person.
A small space can also be disastrous for CO2 levels. One or Two people breathing in a small space quickly turns it into a CO2 chamber, and vent holes alone cannot overcome this in small space.
In short: a larger sauna means better air circulation, more oxygen, less CO2 buildup, and a far more comfortable, authentic heat experience for even one bather.
Why North American Saunas Often Miss the Mark
There are long-standing sauna companies in North America still building with:
- Low ceilings
- Foot bench low to the ground
- Benches at or below the heater level
- Poor or no ventilation
Why does this continue?
Finland has over 2 million saunas for a population of 5.5 million. It’s part of daily life and family tradition. Alongside that comes decades of research, experience, and refinement — most notably from scholars like Dr. Lassi Liikkanen, whose book “The Secrets of Finnish Sauna Design” (now available in English) clearly explains best practices.
In North America, the sauna tradition is newer. Much of the original knowledge was passed along informally — or lost entirely. Some builders simply didn’t know better. Others may have prioritized smaller saunas that are easier to market and ship. And let’s be honest — it’s tough to admit your design philosophy may have been off for decades.
Saunas are often marketed as sort of an appliance that you can buy, just like you would buy a hot tub, or new fridge etc. But it's important to note that a sauna is more akin to an entire room like a bathroom. You can't just go pick up a bathroom for example. When you build an outdoor sauna you are building a full-on new structure that needs many design considerations to function well and be a worthwhile investment long term.
A sauna is an investment, into your lifestyle and well-being.
What a Real Finnish Sauna Feels Like
A true Finnish sauna offers:
- Gentle, full-body heat
- A meditative environment
- Clear air with proper oxygen levels
- Deep relaxation, recovery, and renewal
The Real Benefits Come From Doing It Right
Many of the health benefits linked to sauna use — cardiovascular support, stress relief, and longevity — come from studies conducted in Finland, using authentic sauna conditions. If you want those benefits, your sauna should replicate those conditions as closely as possible: proper heat stratification, fresh air, and space to truly unwind.
Conclusion: It's Time to Relearn
The information is now out there. Thoughtful builders and homeowners are rediscovering what makes a sauna truly great — and why it’s worth doing right. As Trumpkin put it:
“A good sauna is something you should want to go back into again and again. You shouldn’t be crawling out, gasping for breath.”
We owe it to ourselves — and to the tradition — to build better saunas. True Finnish sauna isn't just a hot room, it's a space that can truly upgrade your life.
We Build Authentic Finnish Saunas
We design and build saunas based on the principles above. Whether it’s a backyard sauna kit or a high-performing custom sauna, we believe the best sauna is the one that follows what’s been proven to work—for generations.
📩 Contact us to start your custom build, or explore our DIY log sauna kits.
