Seismic Retrofit and Upgrades

Los Angeles Seismic Ordinance Update (Ordinance 183893 and Ordinance 184081)

In November 2015, the City of Los Angeles approved an ordinance mandating the seismic retrofit of wood soft-story structures and non-ductile concrete buildings within the city. There are many structures in the city that will need to be analyzed and seismically upgraded, to meet the seismic performance requirements of the city ordinance. Other cities in Southern California are also implementing similar ordinances, such as Santa Monica and Beverly Hills. Our structural engineers are actively involved with owners, architects, contractors, and developers to find ways to be part of this effort to make cities with high seismic activities more seismically resilient.

Question: Do you need to retrofit your building?

The City of Los Angeles is currently implementing an ordinance, 183893, that will require seismic retrofits of all wood-frame soft-story buildings constructed before 1978 as well as non-ductile concrete buildings from the same era. If your building consists of soft-story irregularity or is considered non-ductile concrete buildings, this will help explain further:

1. Soft-Story Buildings

Owners of soft-story buildings will have to adhere to the following steps to obtain a certificate of compliance.

a. Receive a letter ordering owners to comply

b. Submit proof of retrofit done in the past or plans to retrofit and demolish within 2 years

c. Obtain a permit to start construction or demolish within 3.5 years*

d. Complete construction within 7 years*

* Time is calculated from the receipt of the order to comply letter.

2. Non-Ductile Concrete Buildings

Owners of concrete non-ductile buildings will have to adhere to the following steps to obtain a certificate of compliance.

a. Receive a letter ordering owners to comply

b. Submit a checklist evaluating the building if it is a non-ductile building within 3 years*.

c. Submit proof of retrofit done in the past or plans to retrofit and demolish to obtain construction permit within 10 years*.

d. Complete construction within 25 years*.

*Time is calculated from the receipt of the order to comply letter.

How can wood-frame soft-story buildings be retrofitted?

Retrofitting techniques come in a wide variety of forms, including the addition of light-frame wood shear walls or steel moment-resisting frames as required to eliminate the soft or weak story. Some ordinances allow individual wall lines in the soft story to be addressed, while others require that the entire earthquake bracing system in the soft story be evaluated and retrofit as needed. In most cases, a retrofit will not eliminate the available space such as tuck-under parking for future use. It is recommended that the owner to discuss his options with our structural engineers to select the most economical and practical solution for his structure.

How can non-ductile reinforced concrete buildings be retrofitted?

Retrofitting non-ductile concrete buildings can be quite disruptive and involve technical structural engineering work. Solutions of retrofit may include concrete shear walls, steel braced frames, and other structural lateral vertical resisting systems that can be used. It is recommended that the owner to discuss his options with our structural engineers to select the most economical and practical solution for his structure.

House of Engineers, Inc.

9070 Irvine Center Dr. # 200
Irvine CA 92618, US

(949) 767 - 0110