From the Nile to the Rio Grande

Building catenary vaults is "something you get a feel for," says master builder Mauro Rodriguez, who joined Jimenez in the task. "Each vault goes up just a little different, each course is a little different, and that's okay so long as it stays even over the full length. Even each adobe [brick] can be a little different, too. Have you ever looked at a wasp's nest?" he asks. "They build their nests just the way we make these vaults. I think that's where [the Nubians] must have first learned this."

Swan is building her home, which she coolly calls "Prototype Two," some 15 kilometers (10 mi) outside Presidio on a rolling, cactus-strewn mesa of 175 hectares (430 acres) that she hopes, someday, to develop with more homes built on Fathy's principles. But her sights are set first on local low-income adobe housing. As her crew labors on her house, she labors in her office opposite the kitchen, sketching plans, sending reports, soliciting testimonials from engineers and seeking contact with micro-credit lenders and philanthropic foundations. Over the past year, she has worked to convince the Rural Housing Agency (RHA) of the US Department of Agriculture to give the Nubian vault a federal stamp of approval, and this bureaucratic feat promises to allow Presidio residents to receive low-interest mortgages to build all-adobe homes. With further assistance from a development bank, there are now three houses in the planning stage, and a clinic.

"Not many engineers have studied adobe," says Demetrio Jimenez, director of the non-profit Greater El Paso Housing Development Corporation, who has helped Swan navigate the channels of the RHA. "Even fewer have heard of Hassan Fathy or these parabolic vaults." And low-income people, he explains, can't get government-backed loans without an engineer's approval of the house design. "When that engineer signs off, he has some big liabilities if anything goes wrong. They don't sign on something they don't know," he explains. "But from my experience along the border, there's a lot of families building their own homes anyway; that's just the way people do it here." Swan's ideas thus "lend themselves excellently" to existing local practices.