What a conversion is
A tub-to-shower conversion replaces a standard bathtub, and usually its wall surround, with a shower built into the same alcove. Instead of lifting a leg over the side of a bathtub, the bather steps over a low curb or rolls straight in. A good conversion for an older adult also adds the details that make showering safer: a seat, grab bars, a handheld shower on a slide bar and a slip-resistant floor.
It is a different project from a walk-in tub. A walk-in tub keeps the soak; a shower gives up the soak in exchange for quicker bathing, less hot water and more room for a caregiver. If you are still deciding between them, our comparison guide covers who each one suits.
Three ways to handle the entry
Standard curb
A curb a few inches high keeps water in the shower with the simplest floor work. Fine for steady walkers, but it can catch a foot or a walker wheel.
Low-threshold
A much lower lip that most people can step over easily. A common choice for conversions in an existing alcove.
Curbless (roll-in)
No step at all, with the floor sloped to the drain. Best for wheelchairs and shower chairs, but it usually means more floor work.
What the work involves
- Removing the tub and surround. Older cast-iron tubs are very heavy and are sometimes broken up to get them out. Steel and acrylic tubs come out more easily.
- Checking what is underneath. Once the tub is out, the installer can see the subfloor and the bottom of the walls. Old leaks sometimes leave soft spots that need repair before anything new goes in. A good quote explains how that is handled.
- Adjusting the drain. A bathtub drain sits at one end; a shower base may need it in a different spot. Moving it is plumbing work, and how hard it is depends on what is below the bathroom (see below).
- Installing the shower base or pan. A one-piece base is quick and leak-resistant; a sloped, curbless floor takes more preparation.
- Walls. Solid wall panels go up quickly and have few grout lines to clean. Tile takes longer and costs more in labor but offers more design choice.
- Blocking for grab bars. Grab bars must be anchored into solid backing, not just drywall or a panel. The best time to add that backing is while the wall is open.
- Valve, shower head and accessories. A pressure-balancing or thermostatic valve helps prevent sudden temperature swings, and a handheld shower on a slide bar lets someone wash while seated.
What we see in Denver-area homes
- Basement or crawlspace below the bath. Moving the drain is usually simpler when there is open access beneath the bathroom. On a slab, concrete may need to be cut to reroute it, which adds time and cost.
- Older close-in houses. Homes from the middle of the last century often have heavy cast-iron tubs and older piping. It is worth having the installer look at the supply lines and drain while the wall is open.
- Upstairs bathrooms. In many two-story suburban homes the only full bath with a tub is upstairs. If stairs are becoming hard, converting a main-floor bathroom, even a small one, may serve better over time.
- One-bath homes. If the tub you are replacing is the only one in the house, think about everyone who uses it. Some families convert one bathroom and keep a tub in another.
Safety details worth specifying
Federal accessibility standards were written for public buildings, not private homes, but they are a useful reference point for what works for people with limited mobility:
- Seat height. The 2010 ADA Standards set shower seat tops at 17 to 19 inches above the floor.
- Handheld shower. The same standards call for a hose at least 59 inches long that works as both a fixed and a handheld shower.
- Grab bars. ADA grab bars are mounted 33 to 36 inches above the floor. In a home, the right spot is where the bather actually reaches when sitting down, standing up and turning.
- Floor. Choose a slip-resistant surface, and keep a non-slip mat outside the shower too.
The National Institute on Aging also recommends grab bars, non-slip surfaces and a shower chair as basic bathroom fall-prevention steps. Our fall prevention guide goes room by room.
Permits in Denver and nearby cities
Whether a conversion needs a permit depends on the scope of work and the city. The City and County of Denver's residential remodel pages treat like-for-like fixture replacement differently from work that changes plumbing, and moving a drain or supply line is the kind of change that typically calls for a permit. Suburbs such as Aurora, Lakewood and Littleton have their own building departments, and unincorporated areas such as Highlands Ranch go through the county. Your installer should know which office covers your address and pull any permit the work requires. Our installation guide has more on what Denver's permit pages say.
What changes the price
We do not publish one price for a conversion because two jobs that look alike from the doorway can be very different once the tub is out. These are the factors that move the number most:
- Curb type: standard, low-threshold or curbless
- Whether the drain has to move, and whether there is access below or a slab
- Wall panels or tile, and how far up the walls go
- Glass door or panel versus a curtain
- Seat, grab bars, valve type and handheld shower
- Subfloor or wall repair found after removal
- Permit requirements where you live
The fastest way to a real number is a free quote based on your bathroom. If you are looking at funding, our paying for it guide covers Medicare, the VA HISA grant and Colorado programs. Several of those apply to medically necessary bathroom changes in general, not only to walk-in tubs.
Conversion questions
Can a shower fit in the same space as my bathtub?
Usually, yes. Most conversions use the existing tub alcove, which in many homes is about five feet long. The shower base, walls and fixtures are chosen to fit that space.
Is a curbless shower always the better choice?
Not always. Curbless is best for wheelchairs and rolling shower chairs, but it usually needs more floor work. For someone who walks steadily, a low-threshold shower is often enough and simpler to build.
How long does a tub-to-shower conversion take?
It depends on the scope. A conversion that keeps the drain where it is and uses wall panels is much quicker than one that moves the drain, adds tile or builds a sloped curbless floor. Your written quote should give an expected schedule for your job.
Sources
- U.S. Access Board, “Guide to the ADA Accessibility Standards, Chapter 6: Bathing Rooms.” access-board.gov
- National Institute on Aging, “Preventing Falls at Home: Room by Room.” nia.nih.gov
- City and County of Denver, Community Planning and Development, “Residential Interior Remodel.” denvergov.org
- Angi, “Convert a Tub to a Shower.” angi.com
Last reviewed 2026-10-12.