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Los Angeles Soft-Story Retrofit

soft-story retrofit Los Angeles

In our articles we are talking about soft-story buildings quite often and, as already known, the soft-story building is a multi-story structure built with a first floor that is much less rigid than the floors located above, for instance in an apartment with tuck-under parking. They can fail, and they actually have failed during major seismic activity due to unreinforced openings on the ground floor which caused even more movement than the soft-story building could withstand, resulting in the upper floors collapsing on top of it. The Los Angeles Soft-Story Retrofit program is designed to help prevent this from occurring in the future.


Soft-Story Structures in LA

There are an estimated 13,500 soft-story structures in LA alone that have been identified to be in need of a retrofit. Retrofitting soft-story buildings has now become mandatory by the City of Los Angeles as of November 22, 2015.

Mandatory Retrofit Program

Soft Story Retrofitting Isn't Just Recommended, it is the Law as long as in November of 2015, the City of Los Angeles signed into law, the Mandatory Retrofit Program under Ordinance 183893, requiring the retrofitting of wood-frame apartment buildings to better withstand a major earthquake. Structures that are in danger of being catastrophically damaged in the event of an earthquake are to be upgraded within a finite amount of time. This includes soft story retrofitting in Los Angeles county buildings. Los Angeles now has the nation's toughest earthquake safety rules.
From the Los Angeles Times:

“Under the law, property owners will have seven years to fix wood apartments and 25 years to fix concrete buildings. The city has already identified about 13,500 apartment complexes that officials suspect need repairs. A Times investigation in 2013 found more than 1,000 older concrete structures, including landmark buildings in downtown, Hollywood, and Westwood - that require close scrutiny for retrofitting.”

Many more cities in the region are following suit and mandating the same soft story retrofit Los Angeles has signed into law. This is in an effort to avoid devastation and to safeguard residents from harm that has been caused by large earthquakes such as the Northridge quake in 1994.

Earthquake of Significant Magnitude

How does this soft story retrofit law affect you? It is no longer an argument as to whether or not an earthquake of significant magnitude is going to strike Southern California - it is now just a matter of time to find out when. The longer your building doesn’t get its soft story retrofit in Los Angeles, the more likely something disastrous could occur.

There is no doubt that an unreinforced building could collapse, causing irrevocable damage to the structure - and those who reside in it. But did you know that you could be held liable for these catastrophes? There are multiple instances of property and bodily damage stemming from an earthquake resulting in the property owner getting sued for seven-digit figures.

Getting your building the soft story retrofitting Los Angeles structures need is not only a great idea that can save lives as well as your building, and a costly lawsuit but did you know that it can also lessen your insurance premium? Not only that, there are grants, tax breaks, and financial aid that you can apply for to assist you to safeguard your building. Not to mention that you could have your tenants help you pay for these repairs up to 50%!

Soft Story Retrofit Time Table

The following are compliance time frames. Compliance of the Los Angeles soft-story retrofit time table is calculated based on the date the owner received notice.

From the receipt of the Order to Comply:

  • 2 years: Submit proof of previous retrofit, or plans to retrofit or demolish

  • 3.5 years: Obtain a permit to start construction or demolition

  • 7 years: Complete retrofit construction

According to the reports of January 7, 2019 it appears there are about still 4,500 remaining buildings that have to submit retrofitting plans.


non-ductile concrete buildings collapse during an earthquake

Now let’s learn more about Los Angeles Retrofit Program and the ordinance.

The City of Los Angeles recently passed Ordinance 183893, which requires the retrofit of pre-1978 wood-frame soft-story buildings and non-ductile concrete buildings. The goal of the mandatory retrofit programs, under the ordinance, is to reduce these structural deficiencies and improve the performance of these buildings during earthquakes. Without proper strengthening, these vulnerable buildings may be subjected to structural failure during and/or after an earthquake.

Soft-Story Retrofit Program

From past earthquakes, multi-story buildings with weak and/or open-front wall lines creating a soft-story such as buildings with tuck-under-parking performed poorly and collapsed. The goal of the mandatory retrofit program, under Ordinance 183893 and Ordinance 184081, is to reduce structural deficiencies by the most economical and feasible method. Without proper strengthening, these vulnerable buildings may be subjected to structural failure during and/or after an earthquake.
Buildings that are most vulnerable have been identified with the following criteria:

  • Consist of 2 or more stories wood frame construction

  • Built under building code standards enacted before January 1, 1978

  • Contains ground floor parking or other similar open floor space

The program does not apply to residential buildings with 3 or fewer units.

Non-Ductile Concrete Retrofit Program

During the earthquakes at Northridge, Mexico City, and most recently, Christchurch New Zealand, many concrete buildings constructed prior to the 1976 Los Angeles City Building Code provisions, or similar era codes in other countries, performed poorly and collapsed, causing loss of human life, personal injury, and property damage. The poor performance of these older concrete buildings is due to deficiencies in the lateral force-resisting system that render the building incapable of sustaining gravity loads when the building is subjected to an earthquake.
Buildings that are within the scope of this ordinance and require retrofitting are concrete buildings with a roof and/or floor supported by a concrete wall or concrete column, submitted for plan check before January 13, 1977.

non-ductile concrete building

The property owner must comply with the ordinance within the following time limits:

From the receipt of the Order to Comply:

  • 3 years: Submit a completed checklist for review to determine if a building is a non-ductile concrete building

  • 10 years: Submit proof of previous retrofit, or plans to retrofit or plans to demolish a building

  • 25 years: Complete construction

Any concrete building, as defined in the retrofit ordinance, and built pursuant to a permit application for a new building that was submitted before January 13, 1977 is subject to the retrofit ordinance whether the building has been identified by LADBS or not.