Walk-In Shower Sizes: Dimensions, Entry Options and Glass Choices

Who this is for: homeowners planning a walk-in shower, often in place of a tub, who want to know what size fits, how low the entry can go, and whether they can skip the door.

What counts as a walk-in shower

A walk-in shower is a shower you step straight into, with no tub wall to climb over. It has a low curb or no curb at all, and it's usually closed with a fixed glass panel, a door, or nothing. Walk-ins can be tiled or built on a prefabricated base, and they range from a compact square to a long, open shower with a bench.

Walk-in shower sizes at a glance

Most walk-ins land between a 36-inch square and a 60-inch-long rectangle. The table shows common layouts, starting with the code minimum.

Common walk-in shower sizes (interior dimensions)

Layout	Typical interior size	Who it suits	Notes
Code minimum	1,024 sq in, with room for a 30-inch circle (for example, 32 x 32 in)	Tight spaces only	Uniform Plumbing Code minimum; see the note below
Compact square	36 x 36 in	Small and secondary bathrooms	Also the size the ADA uses for a transfer shower
Tub-space walk-in	About 60 x 30–32 in	Replacing a standard 5-foot alcove tub	Fits the old tub footprint; wide fixed panel or sliding door
Comfortable rectangle	48 x 36 in or 60 x 36 in	Primary bathrooms	Room to turn around and add a corner seat
Long or doorless walk-in	60 in long and up, 36 in deep or more	Larger bathrooms	Extra length keeps spray away from the opening
Roll-in style	30 x 60 in minimum	Wheelchair users	ADA roll-in size; usually curbless

A note on the code minimum. Most national guides quote the International Residential Code, which calls for at least 900 square inches and a 30-inch minimum dimension. That isn't the plumbing code Bismarck uses. The City of Bismarck's adopted codes list the Uniform Plumbing Code plus the North Dakota State Plumbing Standards, and the state plumbing board has adopted the 2018 Uniform Plumbing Code as the North Dakota Plumbing Code. The UPC calls for at least 1,024 square inches with room for a 30-inch circle. Treat these as reference points, not a rule for every home: the requirement that applies depends on the jurisdiction, so we confirm it for your address before design. Either way, a minimum-size shower is tight; most people are happier at 36 by 36 inches or larger.

The ADA sizes in the table are a useful reference, but the ADA applies to public buildings, not private homes. Your shower can be sized to the people who use it. To see how we build them, look at our walk-in showers in Bismarck-Mandan.

What fits in a standard 5-foot tub space

A standard alcove tub is about 60 inches long, so a walk-in that replaces it is usually about 60 inches long and 30 to 32 inches deep. That's well above the code minimum and roomy for one person. It usually takes a full-length glass panel with an opening at one end, or a sliding door across the front.

Three things change when the tub comes out. The drain usually moves, because a tub drain sits at one end and a shower drain sits where the new base needs it. The valve and shower head often go higher. And the alcove walls get a new waterproofing system from the floor up. Our guide to converting a tub into a walk-in shower walks through cost and the day-by-day schedule. If the tub space is the one you want to use, you can convert your tub to a walk-in shower without changing the room's layout.

Entry options: standard curb, low threshold, curbless

How you step in is the biggest design choice after size. Lower entries are easier on knees and better for aging in place, but they take more floor work and need good water control.

Walk-in shower entry types

Entry	Step height	Floor work needed	Good fit for
Standard curb	A few inches	None beyond the shower floor	Budgets and the most reliable water containment
Low threshold	A low, often beveled lip	A low-profile base or a carefully sloped tile floor	Most remodels and easier daily use
Curbless	Flush with the bathroom floor	The shower floor is recessed, or the bathroom floor is built up	Wheelchair access and long-term planning

If you're planning for safer daily use, a low threshold is often the right balance. Our guide to aging-in-place bathroom upgrades covers entries, grab bars and seats together.

Why curbless is harder in an existing home

A shower floor has to slope to the drain. With no curb, that slope has to start below the level of the bathroom floor, so the subfloor and sometimes the joists under the shower must be lowered, or the rest of the bathroom floor raised to match. On a basement slab, the concrete may have to be cut. Whether it's practical depends on what's under the floor. In an existing home, curbless works when the floor framing can be recessed, or in a basement where the slab can be cut; otherwise a low-profile curb about 2 inches high is the usual alternative.

Doorless walk-ins: how deep it needs to be and where water goes

A walk-in without a door works when the shower is long enough that spray doesn't reach the opening. The shower head goes on the wall farthest from the entry, the floor slopes away from the opening, and a fixed glass panel blocks the direct spray. A linear drain at the back wall helps keep water from reaching the bathroom floor. Many doorless layouts start at around 60 inches of length and 36 to 42 inches of depth, but that's a starting point, not a requirement: the spray, the shower head and the drain location decide what works in your room.

One more thing to know in North Dakota: an open shower holds less heat. In January, a doorless shower feels cooler than one with a door, so plan the bathroom heat and the fan location with that in mind.

Glass: fixed panel, framed door, frameless door

Glass changes the look, the cleaning and the price.

• Fixed panel. One panel, no door. Simple and easy to clean, but it only works with a layout that keeps spray inside.
• Framed door. Metal frames around the glass. Usually the lowest-cost glass option, but the frame edges collect water and soap film.
• Frameless door. Heavier glass with minimal hardware. Cleaner look and fewer edges to wipe, and usually the most expensive choice.

Glass is measured after the tile is finished and made to fit, so it often goes in after the rest of the shower is done.

Drain choices: center vs. linear

A center drain sits in the middle of the floor, and the floor slopes toward it from all four sides, which works well with smaller floor tiles. A linear drain is a long, narrow channel, usually along the back wall or at the entry. The floor slopes in one direction, so you can use larger floor tiles, and it suits low-threshold and curbless entries well.

Bench, niche and grab-bar blocking: plan them before tile

Benches, niches and grab bars are easy to plan and hard to add later. A built-in bench needs its own waterproofing. A niche has to be framed between studs and fully wrapped in the membrane. Grab bars need solid blocking behind the wall, which only goes in while the studs are open. Even if nobody needs a grab bar today, blocking costs very little to add during the remodel.

Frequently asked questions

What size is a walk-in shower?

Most walk-in showers are between 36 by 36 inches and 60 by 36 inches. A walk-in that replaces a standard tub is usually about 60 by 30 to 32 inches. The Uniform Plumbing Code, which Bismarck lists among its adopted codes, sets a minimum of 1,024 square inches with room for a 30-inch circle; the requirement for your address depends on the jurisdiction. Showers that small feel tight.

How wide should a walk-in shower be?

At least 36 inches is comfortable for most adults, and 30 to 32 inches works in a tub alcove that's 60 inches long. If you want a bench, or room for a helper, go wider. Leave space outside the shower too, so you can step out and dry off without bumping the toilet or vanity.

Can you have a walk-in shower without a door?

Yes, if the shower is long enough and the layout keeps spray away from the opening: the shower head at the far end, a fixed glass panel, and a floor that slopes away from the entry. Small doorless showers tend to splash the bathroom floor. Expect a doorless shower to feel cooler in winter.

Planning a walk-in? A five-foot tub opening can be a starting point. We measure the usable shower area, check the floor and drain, and explain whether a low threshold, curbless entry or doorless layout will work. Call or text Viktor at (701) 329-9659 with your town, photos and what you want to change. Our office follows up during business hours. You can also request a free written estimate through the form on this page.