A curbless shower has no step. You walk in, or roll in, on the same floor you crossed to get there. The reason it fits so many houses here is a matter of dimensions: a standard 60-inch alcove tub has exactly the footprint of a 60 by 30 inch roll-in shower. The fixture most people fall getting out of occupies the same space as the one with nothing to step over.
This guide covers the numbers that matter, the two St. George problems that make the job different from the version on a national website, and the honest answer to whether the work prevents falls. It is written about staying in a house, not leaving it.
A private home is not an ADA facility
The Americans with Disabilities Act governs public accommodations: stores, clinics, hotels. It does not govern your bathroom. What people want when they ask for "ADA" is the set of dimensions and clearances in the ADA standards and in ANSI A117.1, the accessible-design standard those numbers come from. Those are a design benchmark, and a good one, worked out for wheelchairs, walkers and a person steadying herself on a wall.
One number gets published wrong more than any other. Grab bars are designed and tested to 250 pounds of force. There is no 500-pound requirement in any code or standard; that figure traces to product marketing and to people informally doubling the real number. We say 250 because that is what the standard says.
The numbers that matter
Exact mounting heights, bar diameters and clearances come from ANSI A117.1, and from your occupational therapist if you have one. Send the recommendations; we build to them.
- Grab bars: rated at 250 pounds-force. Into solid blocking when the wall is open, or rated retrofit anchors when it isn't. Placed at the toilet, the shower entry and the shower seat.
- Floor tile: a wet dynamic coefficient of friction of 0.50 or higher. The 2022 revision of ANSI A326.3 moved barefoot wet areas into their own, higher category; the 0.42 on some tile boxes is for a different category of floor.
- A hand-held shower on a slide bar, so the spray comes to the person.
- A fold-down or built-in seat, with a bar within reach of it.
- Lever handles, rocker light switches, a comfort-height toilet.
- Lighting and contrast planned for older eyes; the Illuminating Engineering Society publishes a recommended practice for older adults and we work from it.
- Large-format wall tile with as little grout as the layout allows, for a reason explained below.
Grab bars that don't look like grab bars
The objection to bars is almost never that they don't work. It is that they look like a hospital. The answer is a bar that is also a towel bar or a shelf, rated to the same 250 pounds and anchored the same way. Built so it doesn't look built.
During a remodel the wall is open, and solid blocking goes in behind every place a bar might ever go, including places you don't want a bar today. That costs a few pieces of lumber now and nothing later. On a finished wall, rated retrofit anchors do the job, installed to the rating, into the material that is actually there. A suction-cup bar is a decoration.
The St. George problem: the floor is a slab
A curbless shower has to drain, so the shower floor sits lower than the bathroom floor, or the bathroom floor comes up to meet it. On a joisted wood floor that is carpentry. On a slab-on-grade house, which is most of St. George, it is concrete: the pan is recessed into the slab, or the surrounding floor is built up over it. The second option adds a small step at the bathroom door, which is often the trade-off worth making. It is a different job from the one on a national website, and it is priced as one.
Then the warning that belongs on any page about cutting a slab. Some slabs are post-tensioned: steel tendons run through the concrete under tens of thousands of pounds of force each. Cutting one blind can kill someone; the strand releases its energy instantly and whips out of the concrete, and the slab loses the reinforcement that tendon provided. Post-tensioned slabs are the standard engineering response to expansive soil, and St. George's blue clay is exactly that soil, so the odds a local home sits on one are real. How common they are here has not been confirmed, and we say "may be" until it is.
How to tell: round, grouted stressing pockets two to three inches across around the slab edge; a placard in the garage reading "POST-TENSIONED SLAB, DO NOT CUT OR CORE"; tendon layout drawings in the builder's or county's plan file. No visible pockets is not proof; stucco and patios cover them.
What a careful contractor does: establish whether the slab is post-tensioned before anything else, and if in doubt, treat it as if it is. Get the tendon drawing. Scan the cut area with ground-penetrating radar and mark every tendon on the floor. Keep the cut between tendons. If a tendon can't be avoided, stop; that is a job for a structural engineer and a post-tensioning specialist, not a plumber. On some slabs the right answer is to build the floor up rather than cut down.
The other St. George problem: the water
The City of St. George tells residents to set water softeners to 18 grains per gallon, maximum 22. At that hardness a glass shower door etches and grout stains, and no amount of squeegeeing keeps up. On a curbless shower that is a cleanability point, and cleanability is what keeps a shower usable for someone who no longer wants to scrub on her knees.
So the design changes. Large-format wall tile, to minimize grout lines. A curbless layout that does not need a glass door at all, because the floor slope and the spray placement keep the water where it belongs. And a softener, which takes hardness at the tap to functionally zero to one grain and is the only thing that fixes the problem rather than managing it. The softener is a plumbing job; we do both.
Does this actually prevent falls? The honest answer
The best evidence is a 2023 Cochrane review of environmental interventions for preventing falls in older people at home. Two results, reported together. In adults at higher risk of falling, home modification reduced the rate of falls by 38 percent, high-certainty evidence. In the general older population, unselected for risk, it showed no effect, a rate ratio of 1.05, also high certainty.
That means two different conversations. If someone in the house has a history of falls or a mobility limitation, the shower is a safety measure with strong evidence behind it. If you are 68, healthy, and playing pickleball at the Senior Games, it is not a safety device and we won't sell it as one. It is a better bathroom: easier to clean, easier to use, and already right for whatever comes later. Both are good reasons. They are not the same reason.
Age matters more than the headline number suggests. The CDC's fall-injury rate roughly doubles at each step from 65 to 74, to 75 to 84, to 85 and over, on the order of 112, then 241, then 515 per 100,000. The 75-plus household is where the safety case is strongest.
Walk-in tub or walk-in shower?
We install both, so take this as a comparison rather than a pitch. A walk-in tub fills and drains with the door closed and you inside it, so you sit in an empty tub while it fills and a cooling one while it drains. The door seal is a wear item, and a failed seal in a full tub is a flood. The threshold is lower than a standard tub but it is not zero. A curbless shower has none of those failure modes and fits the same 60-inch alcove. The tub wins when someone wants to bathe sitting down and soak, which a shower cannot do. We have a longer comparison on its own page.
On resale, the usual worry is whether removing your only tub hurts value. In Washington County, where the Census puts 22.4 percent of the population at 65 or over, a no-step shower is a feature a large share of buyers are looking for. If the house has a second bathroom, we generally recommend keeping a tub there.
Your HOA, and doing it in phases
A bathroom is interior work. Since May 6, 2026, Utah Code § 57-8a-212(4)(n) bars an association's declaration from restricting the interior of a dwelling except as reasonably necessary for the safety of adjacent lots, and under the Fair Housing Act an association cannot deny a reasonable modification for a disability, including a walk-in shower or grab bars. Our HOA approval guide has the details.
The work can be staged: the shower now, the toilet and lighting later, the second bath after that. Universal design, the idea that a space should work for as many people as possible without adaptation, is a different discipline from accessible design, which solves a specific limitation. A curbless shower is universal design. It looks like a nice bathroom because it is one.
What we’d do at your house
We measure the alcove first, because in most houses here a 60 by 30 roll-in shower fits where the tub is without moving a wall.
We check the slab for post-tensioning before we quote, and if there is any doubt we quote the job as though it is.
Blocking goes in behind every plausible bar location while the wall is open, whether or not you want bars today.
Tile is specified to a wet DCOF of 0.50 or higher and the hardware to 250 pounds; the spec sheets go in your file.
If you have an occupational therapist, we build to her recommendations, and we'll do the job in phases if that's easier.
Sources
What this page says comes from the documents below, read in full. It describes them. It is not legal advice. Confirm with your association, your city, or an attorney before you act.
- ADA standards and ANSI A117.1 as the design benchmark; private homes not ADA facilities briefs.txt brief 09
- Grab bar 250 lbf standard; no 500-pound requirement briefs.txt brief 09, brief 13, §5 do-not-publish list; 08-trust-language-bank.md §7
- ANSI A326.3, 2022 revision (DCOF ≥ 0.50 for barefoot wet areas) briefs.txt brief 09
- 60-inch alcove tub equals 60 × 30 roll-in shower footprint briefs.txt §3 finding 2
- Post-tensioned slab identification and safe cutting procedure 01-plumbing-corpus.md §5.5; briefs.txt §5 safety item; playbook and briefs slab-cutting rule
- City of St. George softener guidance (18 gpg, max 22); softened output 0 to 1 gpg 05-environment-water-geology-corpus.md §1.1; briefs.txt §0 finding 1 and brief 09
- Cochrane 2023 review, environmental interventions for preventing falls (38% reduction in higher-risk adults; RR 1.05 unselected) briefs.txt brief 10
- CDC fall-injury rate curve, 65 to 74 / 75 to 84 / 85+ (roughly 112 / 241 / 515 per 100,000) briefs.txt brief 10
- Walk-in tub comparison points (fill and drain time, door seal, threshold, cost, resale) briefs.txt brief 12
- Census QuickFacts: 22.4% of Washington County aged 65+ briefs.txt §5 'check first' item; 06-accessibility-older-user-corpus.md §0 (city 21.8%)
- Utah Code § 57-8a-212(4)(n); Fair Housing Act reasonable modification briefs.txt brief 02; 03-hoa-corpus.md §2.4
- Lever handles, rocker switches, comfort-height toilets, hand-held shower, IES recommended practice, universal design vs accessible design briefs.txt brief 13
- Voice: 'staying, not decline'; 'built so it doesn't look built'; phases; OT recommendations 08-trust-language-bank.md §7 accessible living