Since Los Angeles joined San Francisco Bay Area cities last October in tightening seismic standards for non-ductile concrete buildings and multi-family, wood-frame structures with parking underneath (ENR 11/9/15 p. 16), seismic retrofit work in those cities has been booming. Structural bracing for some 15,000 buildings—built before a 1976 Uniform Building Code update—is expected to drive demand for the next 25 years.
“There aren’t enough contractors to do it all,” says Dennis Cameron, DL Cameron Construction, Oakland, Calif.
For the seismic liability known as a “soft story,” a steel moment frame is installed to connect the second story to the foundation, thereby increasing lateral load resistance.
Cameron says the price of retrofits ranges from $60,000 to $450,000, depending on the building. Installation of modular frames can be straightforward, if no unforeseen problems, such as asbestos abatement, are encountered, he says. Cameron says he tries to streamline the work so he can keep out of the way of tenants and move onto the next job.
“I prefer installing Hardy Frames because they come certified-welded and in one piece. Simpson [frames] costs me 15% to 20% more, plus costs me for labor to bolt the frames together,” says Cameron. Insurance is the biggest hurdle, he notes. His firm has a $5-million liability policy. “You can’t touch anything here without at least a $2-million policy,” he says.
“I hope everybody adopts the program and educates the owners because it’s a dangerous situation,” says Massoud Abolhoda, planning and development building official for Santa Barbara County. He is pushing for Santa Barbara to adopt the same requirement. “Prevention is a lot cheaper than fixing afterward,” he says.