Not always. A frameless door hinged to a wall with structural framing behind the tile can hang without a header. National Glass Association guidance says a header must be used where a fixed side panel carries a hinged or sliding door. Elsewhere, panel size or hinge layout can call for a header or support bar.
The National Glass Association's heavy glass door manual defines a header as "the horizontal frame member which forms the top of a door opening." On a frameless shower enclosure it is a slim metal bar across the top of the glass, fastened at the walls and tying the tops of the fixed panels to each other and to the structure. The glass still stands on the curb; the header braces its top edge. That matters because the National Glass Association's shower guidance says suspended panels are not recommended in a frameless enclosure, and because the same guidance says the taller and wider a structural side panel, the more bracing or anchoring it needs.
A header braces the glass without wrapping its edges. It is not a track, which is what sliding doors run on. It is not a seal either; what keeps water in on a frameless door is covered in the frameless leak answer. It is finished to match the hinges, in polished chrome, brushed nickel, matte black or oil-rubbed bronze. Holding a true horizontal across a crooked opening is one more job a header can do, and the crooked-wall answer covers it. The transom that closes the top of a steam enclosure is part of steam sealing, explained separately.
The header question turns on what holds the door. The National Glass Association says structural wall construction is normally required to support the weight of a door hinged off a side wall, so a wall-hinged door with studs or blocking behind its hinges puts its load into the building. A door hinged to a fixed glass panel puts its load into that panel instead. Where a side panel carries the load of a sliding or hinged door, the association's guidance says "a header must be used for safety and functionality," and that is why such a panel may end up with only one exposed frameless edge.
Outside that case, the choice rests on the specific hardware. One shower door maker's published installation guidelines say a support bar or header may be required for stability depending on panel size and hinge layout. A support bar does the bracing job with a single bar run from the top of a fixed panel to a wall, which keeps more of the top edge open. Neither of those sources puts a number on the door width or panel height at which a header becomes necessary, so the hardware maker's limits and the conditions found at the measure decide it. The cost side, header or headerless on the hardware line of a quote, sits with the custom shower door pricing answer.
A header can go on an existing frameless door only where the glass and walls allow it. The header has to run level across the panel tops and fasten into framing at the walls, and tempered glass cannot be drilled or notched after tempering, so any fitting that needs a new hole in a panel rules that panel out. A measure of the enclosure as it stands decides.
No. A header is one slim line across the top, finished to match the hinges, and the side edges of the glass stay bare. The National Glass Association defines a frameless operating panel as one "with no full-length metal attachments on the top, sides or bottom," and on a hinged door the header runs above the glass rather than along the door's own edges.
Whether a header belongs on your enclosure comes down to what sits behind the tile and how the door hangs. See full enclosure displays at the Lodi showroom, Monday to Friday 9 to 5 and Saturday 9 to 4, or book the free in-home measure.
