At the restaurant at New York’s Museum of Modern Art, the restroom has stalls open to any gender and sinks in a common area. The setup is similar at the Press Lounge in Manhattan, at the Bliss Rebar in Scottsdale, Arizona, and at dozens of other establishments. While politicians argue and courts weigh in, businesses are forging ahead with new bathroom designs.

The most private of public spaces has been evolving for more than a decade, in the interests of privacy and more equitable distribution for women and the disabled. Now the pace of change is quickening as the U.S. grapples with demands that transgender people be allowed to use the toilets of their choice.

“It’s taken on a level of intensity and interest,” says Erik Kocher, a principle at Hastings+Chivetta architects in St. Louis who counts about a half-dozen different alternative-bathroom blueprints on the boards at the firm. “It’s much more out there.”

To be sure, lavatories in most big venues, such as sports stadiums, will likely continue to be multiple-stalled and gender-segregated because of building-code requirements. But retailers including Target Corp., Starbucks Corp. and Barnes & Noble Inc. have set new rules or clarified policies to allow customers to make privy choices that don’t correspond to their birth genders. And prototypes in restaurants, on college campuses and elsewhere show how the public-latrine paradigm is shifting.

Grossed Out

Codes written before the current transgender-access debate are driving some changes. The International Codes Council, whose edicts are adopted by most U.S. states and municipalities, issued regulations that in 2018 will require individual-user public toilets to be gender neutral, with door signage declaring them so. It’s too soon to know whether the ICC will address the multiple-user question when it crafts its next rulebook, for 2021.

Public bathrooms are a political hot potato and a very personal matter. Some women, for instance, might not care who’s in the next stall but wouldn’t be thrilled about applying mascara next to a guy washing his hands. Others are grossed out at the idea of sitting where a man just did his business. In Yelp reviews of restaurants with unisex facilities, opinions are all over the map, with people applauding the accommodations or calling them creepy. Some men don’t like the idea of urinals going the way of the outhouse — but lavatories are now on occasion being constructed without them.

Stone Benches

The transgender factor will propel experimentation with more individual but equal spaces, says Terry Kogan, a professor at the College of Law at the University of Utah who studies restrooms and transgender issues. The bottom line: “People want options for privacy.”

That explains the orders for floor-to-ceiling stall panels flooding into Ironwood Manufacturing Co. in Snohomish, Washington, where co-owner Mark Nielson says transgender access has become a concern for some customers.

The search for a widely acceptable comfort room is probably 18 centuries in the making. The Romans had the first documented public latrine, according to Zena Kamash, a lecturer in Roman archeology and art at the University of London. Patrons back then sat cheek to jowl over holes in stone benches, with rushing water below carrying away the waste.

In the U.S., Massachusetts first codified the gender-specific concept in the 1880s, as commercial buildings began embracing indoor plumbing. Such differentiation was the law of the land by the 1920s. Small businesses had individual-user amenities, and those whose cramped quarters allowed only one had to make it unisex — or, in today’s parlance, gender neutral.

Cabana Style

Now, in North Carolina — where a new law bars people from public restrooms that don’t correspond to their birth sex — Charlotte’s Westin hotel is adding a single-user, all-gender facility to its second-floor meeting area. The American Restroom Association worked with the city of San Diego to design a unisex-stall bathroom at Kellogg Park.

In 2014, during exhibitions that featured transgender artists, the Whitney Museum of American Art in New York made restrooms on one floor all gender. People not comfortable with that were directed to traditional alternatives elsewhere, says Danielle Linzer, director of access and community programs. The new Whitney building has several single-user gender-neutral units, though no multi-user unisex commodes.

At Hastings+Chivetta, architects are working on a college recreation facility with cabana-style showers rather than a central locker room. Clients are testing new ideas, Kocher says. One, a university in the Midwest, asked for a three-story building with 18 single-user restrooms. It would be cheaper to have multiple-stall rooms, but the route the school picked is popular because it takes gender identify out of the equation.

“Colleges and universities have been on the cutting edge of this,” Kocher says. In some cases, designers face resistance from enforcers of local building codes that require ratios of men’s and women’s rooms. “Zoning rules are definitely behind the times,” he says.

Transgender people aren’t asking for a new model, says Kasey Suffredini, chief program officer with Freedom for All Americans, an advocacy group. Their demand is simply for the right to use the lavatory that fits their gender identify, she says. “It’s not for gender neutral bathrooms. It’s not for single stalls. This is just where the long-standing discomfort with restrooms intersects with discomfort with minority identities — and then we have a fight over bathrooms.”