Eighteen months after Los Angeles passed the nation’s most sweeping seismic retrofit law, more than 15% of the city’s earthquake-vulnerable wood apartment buildings have begun the process of retrofits.

More than 2,100 buildings have either been retrofitted or are in the process of being strengthened out of about 13,500 that have been identified, city officials said. And that’s six years before the first buildings must be retrofitted under the law.

These are the kinds of wood apartments “that crushed people in 1994,” Los Angeles Mayor Eric Garcetti said, referring to the Northridge earthquake, which killed 16 people when the upper floors of an apartment complex collapsed on the ground floor.

“That means property saved, and more importantly, people saved,” Garcetti said of what would happen in the next major earthquake. “We’re just excited to see so many of the folks doing it.”

“We just pray the earthquake doesn’t come before we finish this work,” the mayor said. “And when it does come, we’re all going to be better off.”

It was only 13 months ago that the Department of Building and Safety began sending out retrofit orders for wood apartments with flimsy ground stories that are usually held up above first-floor carports by skinny columns that can snap during shaking.

The city is about halfway through the process of mailing retrofit orders to owners, and that phase is expected to be completed this year.

Officials are also working on finalizing a list of about 1,500 brittle concrete buildings that would also need to be retrofitted if found to be at risk for damage in an earthquake. The Department of Building and Safety first prioritized buildings with 16 or more units and three or more stories; all of those structures have been ordered to comply with the law.

“We know that this work will save lives,” Garcetti told scientists and community leaders who gathered at the mayor’s residence to talk about seismic safety. “We are two years ahead of any other big city in America on the work that we’ve done.”

Garcetti also announced three new initiatives:

Localized preparedness: Work on preparedness plans specific to each of L.A.’s neighborhoods.

Resilience hubs: Work with community organizations to develop emergency neighborhood “resilience hubs,” where residents might meet, charge phones and stay in touch with first responders and where water, food and first aid supplies could be stored.

Seismic safety task force: Reconvene a mayoral committee on earthquake safety “to develop new recommendations to keep our buildings safe.”

Garcetti declined to say whether steel-frame buildings should be required to be retrofitted, as Santa Monica this year reaffirmed it would do.

“The whole point is to convene it to try to look at what’s next,” Garcetti said. “Everything will be on the table.”

Wood apartments

Estimated 13,500 buildings

298 retrofits were completed; 1,841 are underway

Orders to retrofit began being issued in 2016, and will continue this year

After receiving an order to comply, there are deadlines of: two years to submit plans to retrofit or demolish, or submit proof of a previous retrofit; 3½ years to obtain a permit to start construction or demolition; seven yearsto complete construction.

Brittle concrete buildings

Estimated 1,500 buildings

The Department of Building and Safety is still working on creating a list of suspect buildings

After receiving an order to comply, there are deadlines of: three years to submit information to the city to determine if the building is a “non-ductile” concrete building; 10 years to submit plans to retrofit or demolish the building, or submit proof of a previous retrofit; 25 years to complete construction.

ron.lin@latimes.com

Twitter: @ronlin