Guide to Shower Door Opening Sizes

Glass shower door in white marbled bathroom with white tub and large window

The Spruce / Christopher Lee Foto

When you are building a new shower for your bathroom, one of the last steps is to install the shower door. If everything has been perfectly built prior to this, the shower door will swing freely, closely precisely, and keep all of the water in the shower enclosure.

But if you get that measurement wrong, it is very difficult to reverse previous work. Learning about common rough-in door openings in conjunction with shower door sizes will make the installation go smoothly and cleanly.

Standard Shower Door Sizes

Shower door sizing is as variable as the bathrooms they are installed in and the needs of the homeowners. But the two common standard shower door sizes are:

Pivot or Swinging Showers

Most pivot or swinging shower door units are 48 inches wide with the actual walk-in door opening being 26 1/2 inches wide.

Sliding Showers

Most sliding shower door units are 60 inches wide with the actual walk-in door opening being around 22 inches wide to 25-3/8 inches wide.


The minimum allowable shower door width is 22 inches wide: Anything narrower than that may not be up to code.

Measuring for a Shower Door

Whether measuring a shower or a shower/bathtub combination, measure the width by running a tape measure or a laser measuring device from side to side. Measure in two places: at the top and at the bottom. It is important to take these two measurements because walls and alcove enclosures may distort over time or may have been built slightly out of square in the first place. Go with the largest of the two measurements and round up to the nearest 1/8 of an inch.

For height, measure from the side of the bathtub/shower or from the curb on showers. As with the width, measure twice: once at the left and once at the right. Choose the largest of the two measurements and round up to the nearest 1/8 of an inch.

Upon installation, shower doors and their frames do have a bit of flexibility to account for walls that are slightly out of square. That said, you should still get this measurement as accurate as possible.

Bypass or Sliding Door Dimensions

Alcove shower/bathtubs commonly are 60 inches wide and their bypass or sliding doors are usually about 58 inches. When framing the alcove, do not add any extra space to accommodate the shower/tub; it must be exactly 60 inches.

This dimension might be direct-to-stud or between two wall coverings. Direct-to-stud installation refers to a pre-fabricated unit with coordinated surround walls that screw directly to uncovered wall studs. The three walls enclosing the alcove are framed, but no water-resistant wallboard or cement board is installed on top of the studs. With this type of installation, the shower/bathtub itself is slightly less than 60 inches. This gap varies from one manufacturer to another but usually is around 59 7/8 inches. Other alcove installations have wall coverings such as drywall or cement board on the studs.

On the left and right side of the shower door is a metal frame. This frame, plus the need for a slight space on each side of the shower door, reduces the total shower door width in these 60-inch alcove applications to 58 inches.

Sliding shower doors range from 45 inches to 47 inches. Wider sliding shower doors will be 57 inches to 59 inches wide. Most shower doors are 79 inches high.

Frameless Shower Door Dimensions

Frameless shower enclosures are popular because they provide a maximum amount of light in the shower stall and they eliminate the visual impact of shower frames.

Another benefit of frameless showers is that they allow for flexibility in sizing. Theoretically, a frameless shower can be as large or small as you desire since glass can be custom-ordered to size or smaller sizes can be joined. In practice, though, most residential frameless shower installations tend to stay within certain prescribed dimensions.

Standard Pivot (Swinging) Shower Door Sizes

  • 39 1/8-inch to 44-inch
  • 27 5/16-inch to 31 1/8-inch
  • 43 1/8-inch to 48-inch

Standard Sliding Shower Door Sizes

  • 56 5/8-inch to 59 5/8-inch
  • 44 5/8-inch to 47 5/8-inch

Standard Return Side Panel Sizes

  • 34-inch to 35-inch
  • 29-inch to 30-inch
  • 31-inch to 32-inch

Frameless shower doors often have one or even two glass side pieces called side lights. The hinge-side piece allows the door to pivot open and closed while maintaining a waterproof seal against the shower wall.

When tiling a frameless shower enclosure, both the cement backer board and the tile or stone should be specified as true dimensions. Hinges, brackets, strike jambs, and all other shower hardware can be taken out of the equation since they will be included in the door opening technical information. The only unfixed, malleable dimension is the thickness of the thinset, but it is far less than might be expected. While thinset may look thick when first when troweled on, it only comes out to 1/16-inch to 1/8-inch after it has been combed with the trowel and the tile is pressed into place.