The Finnish sauna is the classic form of saunabathing: dry heat, wood, an oven with stones and benches on several levels. How hot does it really get there, how does a sauna session go, and how does the Finnish sauna differ from the milder organic sauna? This article provides answers – with figures from sources rather than from the gut.

Note: This article provides general information and does not replace medical advice. If you have any pre-existing conditions, please consult your doctor beforehand regarding your visit to the sauna.

Photo: Wellnesshotel Sonnenhof & Sonnhalde

Finnish sauna: What it is all about

The word „Sauna“ comes from Finnish. In Finland, sauna bathing is part of everyday life: In 2020, UNESCO added the Finnish sauna culture to the Representative List of the Intangible Cultural Heritage of Humanity. According to their data, there are 3.3 million saunas in Finland with 5.5 million inhabitants. The sauna is not only used for body care; people cleanse their bodies and minds there and find peace and quiet.

The centerpiece of the experience is the „Löyly“: the steam that is created when water is poured onto hot rocks. It increases the perceived heat and sweating. The way a steam bath usually works is explained in the article. Sauna steaming: types, procedure and etiquette.

Construction: Fireplace, stones and benches

The cabin is lined with wood and is heated by a stove that can be operated electrically, with wood or on gas. According to Wikipedia, the benches are located in two to three levels at a height of 0.5 to 1.5 meters; the heat gets noticeably stronger the higher up you go. Therefore, those who are not accustomed to the heat should initially sit lower down (ZDFheute).

The smoking sauna: the original form

The smoke sauna is considered the original form of the Finnish sauna. According to Wikipedia, a stone pile is heated with wood for hours to create the smoke. thisisFINLAND, the portal of the Finnish Ministry of Foreign Affairs, describes the heat as soft; it smells of wood smoke.

Finnish sauna: Temperature and humidity

According to thisisFINLAND, the Finnish Sauna Society recommends 80 to 100 °C; some people feel comfortable at 70 °C already. A competition to see who can reach the highest temperature is considered „both silly and unhealthy“ (in the original, „both silly and unhealthy“). Visit Finland lists 70 to 90 °C as the typical range. Cologne Badeschampagner lists 90 °C and 5 to 10 percent humidity for their Finnish steam saunas, which increases to up to 30 percent during the steam bath.

Characteristic	Finnish sauna	Bio-sauna
Temperature	80 to 100 °C (rarely up to 130 °C)	about 45 to 60 °C
Humidity	very low: about 2 to 5 % below the ceiling at 100 °C	about 40 to 55 %
Number of stays per trip	8 to 15 minutes	15 to 30 minutes
Character	dry-hot, with infusion	Mild, moist warm air; considered to be circulatory-saving

The values come from the Wikipedia overview on saunas, which cites the German Sauna Association as a source among others. Operators cite varying figures. For more information on humid heat, see the article Steam bath or sauna.

Process of a sauna session in the Finnish sauna

The Golden Rules of the German Sauna Association describe a typical process. A full sauna session takes about two hours; one should not rush into it and not start on an empty stomach.

Preparation: First, take a shower and dry off thoroughly, because dry skin sweats faster. A warm foot bath also promotes sweating.
Sweating: The sheet is placed under the entire body. Sweating occurs for eight to fifteen minutes, based on your own feeling. In the last two minutes, sit down so that the circulation system gets used to the upright position.
Cooling down: Do not shower or go into the diving pool immediately, but first cool off in the fresh air. Then follow with a Kneipp hose or a jet shower; the sweat must be washed off before entering the diving pool.
Rest: A warm foot bath helps to balance the temperature; after that, a short rest is recommended.
Repeat: Further sessions follow the first. According to the Sauna Association, three sauna sessions are sufficient; more do not increase the effect.

The article summarizes details about frequency, duration, and clothing. Sauna rules for beginners.

How do the Finns do it?

In Finland, there are no fixed times. According to thisisFINLAND, there are usually at least two sauna sessions; you stay as long as it is comfortable and then cool down in a shower, a lake or in the snow. Visit Finland lists a duration of 5 to 10 minutes to up to hours of sauna with cooling breaks. Nudity is common, but a swimsuit or towel is also fine according to Visit Finland.

Finnish sauna or organic sauna?

The Finnish sauna is hot and dry, the organic sauna is significantly cooler and more humid. Those who cannot tolerate heat well or prefer to stay in milder heat for longer will find an alternative in the organic sauna; those who appreciate the steam and intense heat are right in the Finnish sauna. Which option you get depends on your health as well.

The issue of clothing should not be confused with the sauna: the organic sauna and the Finnish sauna describe the climate; the textile sauna describes the clothing. In Germany, bathing attire in saunas is usually not allowed for hygienic reasons, except in special textile saunas (Apotheken Umschau). According to sauna master Romelia Fiering, nudity is not mandatory; as an alternative, she suggests a sauna kilt or a hamam cloth. The house rules always apply. For more information about the textile sauna, read the article Textile sauna in the Black Forest.

Health and contraindications

The Finnish sauna strains the cardiovascular system: According to Barmer, the heart rate rises to about 120 to 150 beats per minute. For healthy adults, sauna use in moderation is considered safe. Among other things, you should avoid it or seek medical advice if you:

Acute infections and fever (see Sauna during a cold), low blood pressure or acute heart problems (Barmer);
Pregnancy – please discuss this with your gynecologist beforehand (Barmer).

You should avoid alcohol before and during sauna use (Barmer). Visit Finland lists people with serious illnesses such as heart problems as a group that should avoid the sauna; thisisFINLAND advises against sweating in cold water after exercising if you suffer from heart problems or high blood pressure. You can find a detailed overview of the study findings and contraindications in the article. Is sauna healthy?.

The panorama sauna at the Sonnenhof & Sonnhalde wellness hotel

Here in Ühlingen-Birkendorf, at 800 meters above sea level, the panoramic sauna with forest views is our Finnish sauna. It is open from 12:00 to 20:00. In addition, there is the textile garden sauna (14:00 to 20:00) and the organic steam sauna (16:00 to 20:00). The sauna is accessible to people aged 16 and over; the wellness area is open daily from 9:00 to 20:00.

Photo: Wellnesshotel Sonnenhof & Sonnhalde

The rest areas „Garden“ and „Forest View“ for the breaks between the sessions are available, as well as a Kneipp water walk, two wellness stations and the „Forest View“ sunbathing area (1,350 m²). An overview of our wellness area can be found in the brochure. Sauna landscape in the Black Forest. You book your stay directly through the Website.

Frequently asked questions

How hot is a Finnish sauna?

80 to 100 °C is usual (Finnish Sauna Society via thisisFINLAND, Barmer); the Cologne Baths list 90 °C. The humidity is very low at a few percent and rises briefly during the soaking process.

How long do you stay in the Finnish sauna?

The German Sauna Association recommends eight to fifteen minutes per session, based on personal comfort, and a total of three sessions.

What does „Löyly“ mean?

That is the name given in Finland to the steam that is produced when hot rocks are poured into a pot.

Do you have to be naked in the Finnish sauna?

In Finland, nudity is common; however, a towel or swimsuit are acceptable (Visit Finland). In Germany, bathing attire is usually not allowed in saunas, except in textile saunas. Please observe the house rules.

What is the difference between a Finnish sauna and a steam bath?

The Finnish sauna is dry-hot, the steam bath is moist-warm at 100 percent humidity. You can find the numbers in the comparison in the post. Steam bath or sauna.

Finnish sauna: temperature, process, difference from the organic sauna

Finnish sauna: What it is all about