Garden Tub to Roll-In Shower: An Accessible Bath, Start to Finish

The oversized garden tub is in thousands of Houston master baths, and in many of them it mostly holds towels. For anyone who uses a wheelchair, a walker or simply has bad knees, it is worse than wasted space. Here is how a garden tub becomes a roll-in shower, step by step, on the slab foundations most homes around here sit on.

Why the garden tub has to go

A garden tub sits in a raised deck, often with a step in front of it, and getting in means stepping up, over and down into slick porcelain. That is a hard move on two good legs. For a veteran with a service-connected injury, an aging parent or anyone recovering from surgery, it is a fall waiting to happen.

The tub also takes up the best floor space in the room. Remove it and the deck around it, and there is usually enough room for a generous shower with no curb, a bench, and clear floor for a wheelchair to turn. The same square footage goes from storage to the most useful part of the bathroom.

We have torn out garden tubs for exactly this reason. The demolition is the easy part. Everything after it, from the drain to the slope of the floor, decides whether the new shower actually works for the person using it.

Plan around the person first

Before anyone picks tile, we want to know who will use the shower and how. Will they roll in on a shower chair, transfer from a wheelchair to a bench, walk in with a cane, or need a caregiver beside them? Each answer changes the layout, the bench height, the valve location and how much open floor is needed.

Turning space matters most for wheelchair users. A chair needs a clear circle or a T-shaped area to turn around, and the doorway into the bathroom often needs widening to let the chair through at all. We measure the chair the person actually uses, because chairs vary more than most people expect.

Think about the future too. Someone who walks in today may need a chair in five years. Blocking the walls for grab bars now, even where none go up yet, costs very little during construction and saves opening the walls later. Planning for the harder case keeps the bathroom useful longer.

Caregivers count as users too. If a spouse or an aide helps with bathing, they need room to stand beside the bench without stepping into the spray, and the handheld shower needs a hose long enough to reach the person without stretching across them.

Demolition and what it usually uncovers

The tub, its deck, the surrounding tile and often the old shower stall next to it all come out. On most Houston slab homes the garden tub’s drain and supply lines run through the deck and down into the slab, so once the deck is gone the plumbing is exposed and we can see what we are working with.

Demolition often turns up water damage that was hidden for years. A slow leak at a tub spout or a failed seal along the deck can rot the framing and the subfloor at the wall. That gets repaired before anything new goes in, because a new shower built over damaged framing will not last.

Dust control matters when someone in the house has breathing problems or simply has nowhere else to go. We seal the doorway, protect the path through the house, and haul debris out daily so the rest of the home stays livable during the work.

Getting a curbless floor on a slab

A roll-in shower needs a floor with no curb, which means the shower area has to sit slightly lower than the bathroom floor or the bathroom floor has to be built up to meet it. On a slab foundation, recessing the shower usually means saw-cutting and removing concrete so the shower pan can slope to the drain while its edge stays flush with the rest of the room.

Many curbless showers use a linear drain, a long narrow grate along one wall or at the entry. It lets the floor slope in one direction instead of four, which is easier to roll across and simpler to tile with large pieces. A center drain can work too, though the four-way slope is harder for a wheelchair.

Moving or replacing the drain under the slab is the biggest piece of this job. The drain needs proper slope back to the main line and a trap below the floor. If the existing drain sits in the wrong spot, it gets relocated by trenching through the concrete, then the slab is patched before waterproofing begins.

Waterproofing a shower with no curb

A curbless shower has no lip to hold water back, so the waterproofing has to extend beyond the shower itself. We run the membrane across the shower floor, up the walls well past the spray zone, and out into the bathroom floor beyond the shower edge, so any water that escapes lands on a protected surface.

Every seam, corner, niche and pipe penetration gets sealed with the membrane system’s own pieces. The drain connects directly to the membrane so water that gets through the grout still finds its way down the drain. A flood test, filling the pan and checking for leaks before tile goes on, is a step worth asking about.

Houston humidity is part of the plan. A bathroom that stays damp grows mildew in grout and behind trim. A properly sized exhaust fan vented to the outside, running on a timer or a humidity switch, matters as much in an accessible bathroom as anywhere in the house.

Grab bars, benches and blocking

Grab bars are only as strong as what they are screwed into. Drywall anchors will pull out under a person’s full weight. We add solid wood blocking inside the walls at the heights where bars will go, before the backer board goes up, and we photograph the blocking so you know where it is years later.

Placement depends on how the person moves. A bar on the back wall helps someone steadying while standing. A bar beside the bench helps with transfers. A vertical bar at the entry gives a handhold while rolling or stepping in. We go over the placement with the person who will use it, standing in the actual room.

A bench can be built in, tiled and waterproofed with the shower, or it can be a fold-down seat mounted to blocking. Built-in benches feel solid but take up floor space. Fold-down seats keep the floor clear for a chair. The right choice depends on who uses the shower and how.

Fixtures that work from a seat

The valve belongs where a seated person can reach it, which is usually lower and closer to the bench than in a standard shower. A handheld shower head on a slide bar lets the user wash while seated and lets a caregiver help without getting soaked. A pressure-balancing or thermostatic valve holds water temperature steady when someone flushes a toilet elsewhere in the house.

Lever handles beat knobs for anyone with weak hands or arthritis. A recessed niche at seated height keeps soap and shampoo off the floor and within reach. Light switches, towel bars and the toilet paper holder get the same treatment, placed where they work for the person in the chair.

Tile choice matters for safety as much as looks. Smaller floor tiles with more grout lines give better grip under wet feet and wheels, and many larger tiles come in textured, slip-resistant finishes rated for wet floors. Matte finishes beat polished ones every time in a wet room.

Doors, toilet, sink and light

The shower is the centerpiece, and the rest of the bathroom has to work too. The door usually needs widening, and a standard swinging door can trap a wheelchair inside the room. A pocket door, or a door that swings out into the bedroom, frees floor space inside the bathroom and lets a caregiver get in if someone has fallen against the door.

The toilet needs clear floor beside it for a transfer and a seat height that suits the user. Comfort-height toilets help many people, though someone transferring from a wheelchair may need a specific height matched to the chair. Grab bars beside and behind the toilet go on the same blocking plan as the shower.

A vanity with open space underneath lets a wheelchair user roll up to the sink. The pipes under it should be insulated or covered so knees never touch a hot water line. A single-lever faucet, a mirror low enough to use from a seat, and outlets within reach finish the sink area.

Lighting matters more than most people expect. Bright, even light with no dark corners helps anyone with low vision or shaky balance, and a motion-activated night light makes the two a.m. trip safer. Switches at a reachable height, placed at the door, mean nobody has to cross a dark room to find one.

Living through the project

A tub-to-shower conversion takes longer than a straight swap because of the slab work, the waterproofing and the cure times between steps. If this is the only accessible bathroom in the house, plan where the person will bathe in the meantime, whether that is a second bathroom, a relative’s house or a temporary setup.

Permits apply when plumbing moves or walls change, and whether the city or the county handles yours depends on where you live. We pull what is required and schedule inspections so they do not stall the job. If you are using a VA grant, there are extra steps covered in another post on this blog.

Geoff has spent years doing ADA modifications for veterans alongside groups like Wounded Warriors, the Semper Fi Fund, Combined Arms and Career Gear Houston. If you want to talk through a garden tub conversion for your house, call (832) 364-6271, and military members and first responders get 10% off.