Building a barrier-free shower

Barrier-Free Shower

We’re often asked to build zero-step master showers. Almost everybody appreciates a curbless shower design, but it’s critical for a user with a disability.
When we’re building a tiled shower, we drop the framing under the shower floor, leaving a recess for the mortar base (Figure 3). Along the front edge of the shower, our tile contractor typically forms a low ridge of mortar, which he tiles over with the shower floor tile. Though it’s only about 1/2 inch high, this low threshold — combined with the sloped base — provides just enough protection to keep water inside the shower (Figure 4).

 
Figure 3. To eliminate the curb in a tiled shower, the author frames the floor with LVLs or sawn lumber rather than I-joists (top left), dropping the subfloor in the shower area about four inches (top right). This leaves room for the sloped mortar base and waterproofing membrane, which laps over the plywood subfloor at the entry by about 12 inches (middle left). Formed with mortar, a slightly ramped threshold helps contain water (middle right). For better wheelchair and walker access, the shower is fitted with double doors (bottom).

Figure 4. To build a curbless shower, the author lowers the floor framing and installs a sloped mortar bed shower base over Chloraloy, a flexible plastic waterproofing membrane. A slightly raised tile threshold helps contain water within the shower area.
Recessing the floor adds about $125 in labor and materials to the cost of a 48-inch-by-48-inch tiled shower. You’ll find that many disabled clients require showers larger than that, depending on their disability, their dominant hand, and how easily they can negotiate the transfer from wheelchair to bench. The size and design of their shower is one of the most important details to discuss with disabled clients.

Other Resources NAHB offers CAPS (Certified Aging-In-Place Specialist) training, a great source of knowledge that has increased my credibility with prospective customers. Other organizations I’ve found to be helpful are Disability Advocates of Kent County (zerostep.org), the Center for Universal Design at North Carolina State University (design.ncsu.edu/cud/), and our local chapter of the Center for Independent Living (dnmichigan.org). Also, even though the Americans with Disabilities Act (ADA; ada.gov) doesn’t apply to residential construction, it can be an important resource during the design-build process. And it’s always a good idea to have a conversation with your local building official about relevant code matters.

Sometimes the customer needs barrier-free access, but the budget doesn’t allow for a tiled shower. In those cases we use a prefabricated unit, which costs a good $2,000 less than a custom job. Most major national manufacturers offer barrier-free molded fiberglass or acrylic showers; if our client doesn’t have a specific preference, we’ve had good luck with models by Aker (akerplastics.com, 800/962-2537).
Rich Kogelschatz owns Heartland Builders, a general contractor in Rockford, Mich.