There's a new breed of activist architects. They may design houses or corporate headquarters by day and medical clinics in Africa or schools in India by night and on weekends. John Dwyer, a partner in the south Minneapolis firm Shelter Architecture, is one of them.

Dwyer recently returned from East Biloxi, Miss., where he has been building the last of six sustainable model homes developed by the international nonprofit Architecture for Humanity.

Since Hurricane Katrina hit 3 1/2 years ago, he's taken University of Minnesota students to New Orleans to build a gallery for two Ninth Ward photographers, led a community design center there and overseen delivery of the Clean Hub, a shipping container that he and his students retrofitted for solar energy and rainwater collection. It's become part of a community garden.

Still idealistic but chastened by reality, Dwyer, 35, has returned to the small sustainable design firm he and his partners opened four years ago.

"John fell in love with that beautiful and frustrating city," colleague Tom Wesbrook said of Dwyer's New Orleans sojourn.

Dwyer admires New Orleans for its "freestanding culture," relatively indifferent to the influence of New York or Los Angeles. "But it's the hardest city I've ever been in to get anything done."

Bonding over lost photos

His New Orleans affair began soon after Katrina, when he met photographers Keith Calhoun and Chandra McCormick through Cameron Sinclair, founder of Architecture for Humanity, which harnesses architects' talents for humanitarian projects. Thousands of their images documenting the life of the city's Ninth Ward were ruined. Although stored in Rubbermaid bins, "everything was soaked," Calhoun said. "We lost 75 percent of our work."

Dwyer and Wesbrook recruited University of Minnesota architecture students to spend spring break building a new studio a block from the couple's flooded home. With lumber salvaged from their old house and what Wesbrook called "unskilled but highly enthusiastic labor," the students managed to turn half of a classic New Orleans double house into a gallery that became an instant community center as those displaced by the flooding moved back.

"People would come and ask, 'Did you take a picture of my mother?'" Calhoun said.

Fascinated by the challenge facing the city, Dwyer took a leave from his firm and from teaching and moved to New Orleans in September 2007 to start the Design Studio at the Neighborhood Empowerment Network Association. The Minnesota native and an assistant consulted with 65 households wanting to build or renovate and oversaw a dozen historic-renovation projects in the Holy Cross neighborhood.

With two people and a budget of $20,000, "we finally realized we didn't have the resources," Dwyer said. "So we developed a stock foundation that people could install and then build their own houses."

Dwyer's frustrations were many: Clients didn't understand how long and how much it would cost to build a house (at least $90,000, not the $30,000 they expected); the culture fed on graft; virtually every contractor was unlicensed -- too many of them were trying to bilk clients out of their relief money.

Almost across the street, actor Brad Pitt's Make It Right Foundation was attracting national magazine and TV coverage with what Dwyer considered overreaching plans to build starchitect-designed houses that were sustainable and affordable. "The closer I got to making an impact, the less people cared," he said.

Working in Biloxi was a relief. Architecture for Humanity's model-home program realistically paired architects with clients. The design Dwyer worked on with Arkansas architect Marlon Blackwell turned the ground floor, which had to remain open for flood control, into a porch shaded by the house above. "There are major issues with building houses 8 feet above the street. It's a street culture," Dwyer said.

Will Dwyer return to the Gulf Coast? Probably. He's also aiming to go to Indonesia, where the government wants to develop Clean Hubs as portable medical centers for disaster relief.

"John's a really good model for our students," said Tom Fisher, dean of the university's College of Design. "He learned that you can transform the world: Just start doing it."

Linda Mack writes regularly about architecture and design.