Sauna vs steam room is a choice between dry heat you can put almost anywhere and wet heat that needs a sealed, plumbed, tiled enclosure. Both make you sweat and both feel good. As a purchase they are not close: one is a cabin you can bolt together in a weekend, the other is a small wet room with a generator behind the wall.
Dry heat against wet heat
A sauna runs hot and dry, so the air does the work and your sweat evaporates off you. A steam room runs much cooler at saturated humidity, so nothing evaporates and the heat feels heavier. People who dislike a sauna often like a steam room, and the reverse, so try both before you commit thousands to one.
What each one costs you to install
A sauna is a dry enclosure. It needs a floor, a circuit and clearances, and a kit can go in a garage or a back yard with no plumbing at all. A steam room needs a waterproofed and tiled space, a sloped ceiling so condensate runs off rather than dripping, a drain, a water feed and a generator sited within reach of both.
Upkeep, and why it decides most buyers
A dry cabin dries itself between sessions and asks for little beyond a wipe and an occasional sand. A steam enclosure is wet every time, so grout, seals and ventilation are ongoing work, and a room that never dries invites mold. If you will not keep on top of it, the sauna is the safer purchase for a home.
Which belongs in your house
Choose the sauna if you want it outdoors, in a garage or in a spare room, if you want it running in twenty minutes, and if you would rather not open a wall. Choose the steam room if you are already renovating a bathroom, you have the fall in the ceiling to build, and you prefer humid heat on your airways.
Questions people ask about sauna vs steam room
Is a steam room hotter than a sauna?
No. A steam room runs considerably cooler but at full humidity, which makes it feel at least as intense because your sweat cannot evaporate.
Can one room be both?
Only if it is built as a steam enclosure with a separate dry heater, which is expensive and compromises both. Most homes that want both put a cabin outside and steam in the bathroom.
Which is cheaper to run?
A steam generator usually draws less over a session because it runs cooler and cycles, but the installation costs far more. Over a few years the sauna is normally the cheaper of the two.