Engineers urge overhaul of Haiti's archaic, anarchic building practices

a project that withstood the tremors. “I was always fighting with him, ‘You are putting in too much rebar,’”’ he said during an interview in Port-au-Prince. “I will never fight with him again.”

Aside from streaks of destruction starkly visible on ravines and hillsides, where buildings, houses, and walls collapsed in top-to-bottom cascades, ruin can seem random on the street. For every collapsed building, another of similar age and design seems to have survived with minimal damage — sometimes across the block from each other.

Fierro and other experts, however, see clear patterns amid the rubble. Dozens of images Fierro posted for analysis on the Web site of the Earthquake Engineering Research Institute highlight common flaws: spindly support columns snapping under too much weight; weakly attached buildings slipping off unstable foundations; unbraced joints separating; loose, load-bearing block or stone walls spilling like toy blocks. “The buildings, as they are built, they’re very fragile,” he said. “As soon as they go, they go completely.”

Where there is steel, there is almost always too little or the wrong kind, said Cynthia Perry, a partner with Fierro in a Van Nuys, California, seismic engineering firm. Some unfinished columns on the top floor of a school under construction in Léogane reflected a common standard. The rebar, she said, was half the diameter called for under California codes, and poorly tied together — suitable for no more than a light residential building. The finished columns holding the floors below broke like twigs. “They’re all too small for major construction,” she said.

A host of other factors certainly contributed to extensive damage on the island, including loose, sandy soils and Haitians’ penchant for adding floors atop existing private homes, government buildings, and even schools. In Port-au-Prince, like many other crowded Caribbean cities, the only place to grow is often up.

That added mass can prove fatal, said Amir Mirmiran, engineering dean at Florida International University. “You can think about the entire ground shaking,” he said. “If you have a bigger mass, you’re going to attract a larger force with it.”

The dangerous practice is so common that when Haitian architect Philippe Léon builds a house, he always tops it with a pitched roof if he has calculated the structure will not support more weight. “I know my clients,” he said during an interview in Port-au-Prince.

Leon and others in Haiti blamed the island’s grinding poverty for rampant construction problems. Outside experts agree it