Steam Room vs Sauna vs Steam Shower: Which Is Which?

What each term means

The three names describe three different ways of delivering heat, and they are not interchangeable. A sauna is a room with a heater that warms air and hot stones, a steam room is a sealed enclosure filled with steam from a central boiler, and a steam shower is a shower enclosure with a steam generator feeding steam into the space.

Saunas can be traditional, with a wood-burning or electric stove heating stones, or infrared, with emitters that warm the body directly. Steam rooms and steam showers both rely on a separate steam generator that boils water and sends steam through a pipe to an outlet head mounted on the wall.

The most useful way to separate the three is to compare them by heat source, humidity, enclosure, and typical installation. Once you know those four factors, you can look at a space and tell immediately what it is.

Heat source

A traditional sauna uses a wood-burning or electric stove to heat a pile of sauna stones, and the room air warms up as it moves past the hot stones. An infrared sauna uses infrared lamps or heating elements that emit energy absorbed directly by your body, with the air temperature staying lower. A steam room or steam shower uses a steam generator, a device that heats water to produce steam and delivers it to the room through a steam outlet head.

The steam generator is the key hardware difference. It needs a dedicated 240-volt electrical circuit, a cold water supply line, and a drain or drain line so the tank can be flushed on a regular schedule. The generator itself is often installed in a closet, under a bench, or in a basement, as long as the space is dry and ventilated.

Because the heat source is different, the way you control the experience is different. A sauna heater heats both the room air and the stones, and you can increase humidity by ladling water onto the stones. A steam system produces saturated steam, so the humidity is already at or near 100 percent and there is no way to make the room drier without stopping the steam.

Humidity

Humidity is the clearest dividing line. Traditional saunas are dry heat: Cleveland Clinic describes them as a small room typically filled with dry heat, with temperatures between 150 and 195 degrees Fahrenheit and humidity usually less than 20 percent. When you pour water on the stones, humidity rises briefly, but the primary environment is still dry heat.

Steam rooms and steam showers are the opposite: the whole point is to fill the space with steam, so relative humidity is near 100 percent and the air feels thick and warm. The temperature is typically lower than a traditional sauna because the high humidity makes the heat feel more intense.

This difference changes how the room is built. A steam room has to be far more airtight than a sauna, because steam under pressure needs to stay inside. The walls need a vapor barrier, waterproof membrane, and sloped ceiling so condensation runs down the walls instead of dripping on you.

Sauna terminology makes the same point. The Finnish word loyly refers to the steam that rises when water hits the stones, and it is a brief event in a mostly dry room. A steam room does not use loyly; it is continuously filled with steam. If you want a deeper dive on the two heat styles, see dry sauna vs wet sauna and sauna humidity and temperature terms.

Enclosure and construction

The enclosure is the second biggest difference. A sauna is a room built of wood, with ventilation designed to let air move in and out while the heater warms it. A steam room is a sealed, tiled or waterproofed space, often with a glass door that seals tightly and a sloped ceiling so condensation runs off.

A steam shower is the most compact option: it is exactly the size of a shower enclosure. As one steam company puts it, an opening as small as 3 feet by 3 feet is enough for a steam shower. That makes it a practical retrofit in an existing bathroom, where a dedicated steam room would need a much larger footprint, on the order of a full extra room.

The construction materials differ too. A sauna can use wood walls, wood benches, and a wood ceiling, and a drain is not a requirement. A steam room needs non-porous surfaces: tile, stone, or a waterproof membrane, plus a floor drain because the steam will condense into water and run down the walls.

The ceiling is a clear giveaway. A steam room needs a sloped ceiling, ideally at a height that keeps temperature consistent, and the ceiling should be sloped so condensation drops run down the wall instead of falling from above. A sauna ceiling is usually flat or slightly pitched, and condensation is less of a problem because the air is much drier.

• Sauna: wood interior, no drain required, ventilated to let air move
• Steam room: tiled or waterproofed interior, floor drain required, tightly sealed door
• Steam shower: same as a steam room but sized to a shower footprint, typically 3 by 3 feet or larger
• Steam room ceiling: sloped so condensation runs down walls
• Sauna ceiling: can be flat or modestly sloped

Typical installation

Saunas are usually freestanding rooms or prefab cabins. They can go indoors or outdoors, and many are sold as kits that you assemble on site. The heater is inside the room, and the electrical work is a dedicated circuit sized to the heater.

Steam rooms are built into the structure of a home or commercial building. They are almost always indoors, tiled, and sealed, with the steam generator located remotely. The generator needs a dedicated 240V circuit and cold water line, and it is usually placed in a closet, basement, or attic near the steam room.

Steam showers are the most common residential option because they fit into an existing bathroom. The steam generator can be mounted under a bench, in a cabinet, or in an adjacent closet, and the steam line runs from the generator to the outlet head in the shower. For a fuller look at this route, see steam shower vs steam room decision and steam room vs steam shower build.

If you are deciding what to install, the space you already have matters more than the name. A house with a bathroom that has high ceilings and a tile enclosure can be a steam shower retrofit. A home with a spare room or a slab foundation could host a sauna cabin. An outdoor area with power can take a sauna kit but not a steam room, since steam rooms are indoor installations.

Which should you choose?

Start with the experience you want. If you like a hot, dry room where you can control humidity by throwing water on stones, choose a traditional sauna. If you want to relax in thick, moist air that wraps around you, choose a steam room or steam shower. If you want both a shower and a steam bath in the same footprint, a steam shower gives you both in the space of a normal shower.

The installation reality also points in one direction. Saunas are available as kits and can be installed by a homeowner or a contractor. Steam rooms and steam showers require plumbing, a steam generator, a sealed enclosure, waterproofing, and a floor drain, so they are more involved projects.

For most people, the practical choice is either a sauna cabin or a steam shower. A sauna cabin gives you the traditional Finnish experience with wood heat and low humidity. A steam shower gives you a shower that is also a steam bath, without needing an extra room.

What to pick for your use

Questions

Is a steam room the same as a sauna?

No. A sauna is a dry-heat room with low humidity, typically under 20 percent and at temperatures between 150 and 195 degrees Fahrenheit. A steam room is filled with saturated steam from a generator, so humidity is near 100 percent and the air feels wet.

What is the difference between a steam room and a steam shower?

A steam room is a dedicated tiled enclosure with a bench and a tight door, filled with steam from a central generator. A steam shower is exactly a shower enclosure, typically as small as 3 feet by 3 feet, with a steam generator feeding steam inside, so the same space works as both a regular shower and a steam bath.

Can a sauna be used as a steam room?

Not really. A sauna is designed as a dry-heat room with wood interior and ventilation. Adding water to the stones raises humidity briefly, but the room is not sealed, so it cannot maintain the near-100 percent humidity of a steam room.

Which is hotter: a sauna or a steam room?

A traditional sauna typically runs between 150 and 195 degrees Fahrenheit with low humidity. A steam room operates at a lower air temperature, often between 100 and 120 degrees, but the high humidity makes the heat feel just as intense.

Do steam rooms need a drain?

Yes, a floor drain is essentially required because the steam condenses into water that runs down the walls and onto the floor. A sauna does not need a drain as a requirement, though a drain can be convenient for cleaning in a commercial setting.

Can I install a steam shower in an existing bathroom?

Yes, that is the most common way. A steam shower can fit an opening as small as 3 feet by 3 feet, and the steam generator can be placed in a nearby closet, under a bench, or in a basement. You will need a dedicated 240V electrical circuit, a cold water line, and a drain line for the generator.