Space decides this one. A sliding door never swings into the room, so it works where a vanity, a toilet or a narrow floor plan sits inside the arc a hinged door would need. The trade is that half the opening stays covered by glass at all times, and the bottom track needs wiping. In a tub alcove that trade is usually easy.
A hinged door needs an arc of clear floor in front of it, and in plenty of North Jersey bathrooms that arc is already occupied by a vanity, a toilet or a radiator. A bypass slider takes it back. The panels ride on a header track and pass each other within the plane of the opening, so nothing ever projects out.
The same geometry lets a slider cover a wide opening economically. Two panels split the span, so a five or six foot alcove is handled by two moderate pieces of glass rather than one oversized door that would demand much heavier hardware to hang safely. Height works in its favor too, since the panels stop at the header and a tall alcove never forces a taller, heavier swinging leaf.
The trade is permanent: half the opening is always behind glass. You enter from either end but never through the middle, which matters if you bathe a child, if a bench sits at one end, or if anyone in the house needs a wide clear entry for balance.
Most bypass systems also put a track on the curb or the tub deck. It holds water, it holds soap film, and it wants a wipe. Frameless bypass units that hang from a top rail with no bottom track exist and solve that, though they raise the hardware requirement and the price along with it. Ask which of the two is being quoted before comparing anything, because a framed bypass and a frameless bypass are genuinely different products that happen to move the same way.
Skip it when the opening is narrow, because splitting a short span leaves two panels too tight to step through comfortably. Skip it in a steam room, where the enclosure has to seal all the way up to the ceiling. And skip it where the deck or curb is out of level enough that a track cannot be set to drain back toward the pan.
Everywhere else the question is honestly about the room rather than the product. Stand in front of the shower, swing an imaginary door through the floor space, and if that arc collides with something, a slider is not a compromise at all. It is simply the correct fixture for the geometry you have.
Yes. A frameless bypass runs heavy tempered panels off a top rail with exposed rollers and no bottom track, which removes the part that collects film. It costs more than a framed slider because the header has to carry the full weight of both panels and the wall anchoring behind that header has to be genuinely solid.
They are the most common tub enclosure there is. The track mounts to the tub deck, the panels run the length of the alcove, and the whole assembly stays inside the tub footprint. The one thing to confirm early is that the deck offers a flat landing surface, since some rolled rims need a filler to sit correctly.
A slider lives or dies on the header being level and the track draining the right direction, and neither is something to eyeball. Someone comes out, measures the opening at three heights, checks the deck, and quotes from real numbers. Residential measures across North Jersey cost nothing.
