A popular choice for closets, bypass doors need no room to swing open, but they allow access to only one side of a closet at a time. Hardware kits are available for openings of 4, 5, 6, and 8 feet. To accommodate a different opening width, simply cut a standard track with a hacksaw.
The kits are designed to work with standard 1-3/8-inch-thick interior doors. If you use thicker doors, they may interfere with each other as they slide. Thinner doors may have a wide gap between them. The combined width of the doors should equal the width of the opening plus at least 1 inch. This provides 1/2 inch of overlap between the two doors when they are closed.
Some minor variations exist among bypass door kits from different manufacturers, but they are all easy to install. Check the manufacturer's directions carefully before you start. Expect to spend an hour or so installing a pair of doors and hardware. You'll need to finish the opening with wood jambs or drywall before you begin.