Sealing a steam enclosure means closing the top, not just the sides. The glass runs full height to a header or a fixed transom, every door edge carries a gasket, and the perimeter joints are siliconed so vapor cannot escape. A latch or magnetic catch holds the door shut instead of letting it swing free.
Steam rises and will leave through any opening above your head, so a steam enclosure is closed at the top. That is done with glass running to the ceiling, with a fixed transom panel above the door, or with a header carrying a hinged vent panel you can crack open after a session to let the space dry. Whichever detail is used, the joint where that top piece lands is sealed to the tile or the ceiling.
This is the single biggest difference between a steam enclosure and an ordinary shower door, and it is settled before any glass is cut. Ceiling height, header position and transom size all come off the measure, so a steam job is worth talking through while the walls are still open rather than after the tile is finished. A steam enclosure is heavier overall too, since the glass runs higher and the header itself has to be anchored into framing.
Every edge of a steam door carries something. The hinge side gets a seal that closes the swing gap, the strike side gets a wipe or bulb seal that compresses when the door shuts, the bottom gets a sweep, and the top gets its own seal against the header or transom. Vapor travels on very little pressure, so a gap that would be harmless on a regular shower will fog the bathroom in minutes here. None of these gaskets are exotic parts, but they are matched to the glass thickness and to the specific hardware, which is why a steam door is ordered as a set rather than assembled out of whatever fits.
Where glass meets tile, and where the bottom channel or panel meets the curb, silicone does the work. It runs the outside vertical joints and gets tooled rather than left as laid. Steam also raises the standard of everything behind the glass: the room has to be built as a steam room, fully waterproofed, with a ceiling pitched to run condensate down the wall instead of onto you. Give the silicone its cure time before the generator is fired for the first time.
It is worth having. A hinged transom lets you open the top of the enclosure after a session so the space dries out instead of holding warm damp air against the tile and the hardware. It is not the only way to dry a steam room and the bathroom exhaust does plenty, but a vent is the simplest option and costs nothing to run.
Only if the enclosure behind the glass was built for it. Steam demands a fully waterproofed shower, a sloped ceiling, and a room the vapor cannot leak into, and those are tile and framing decisions. New full height glass can go into the opening at any point, but the wall assembly has to be right first, so talk to your tile contractor early.
Ceiling height, header detail and where a transom lands are far easier to settle while the walls are still open. Bring the bathroom plan to the Lodi showroom, or have us out for the free measure once the substrate is set, and the enclosure gets drawn to fit.
