Wood-Frame Soft-Story Structures

Santa Monica

The city of Santa Monica developed a seismic retrofit plan following the 1994 Northridge earthquake. It was the first city in the Southern California region to establish aggressive regulations targeted toward wood-frame soft-story structures. However, many buildings within Santa Monica did not comply with this ordinance.

To update the outdated ordinance, the city of Santa Monica passed a comprehensive seismic retrofit program on March 28, 2017. In addition to wood-frame soft-story structures, the program also addresses unreinforced masonry, concrete tilt-up, steel moment frame, and non-ductile concrete buildings. Amendments to the seismic retrofit program regarding wood-frame soft-story buildings can be found in Chapter 8.72 of the Ordinance.

Scope

Santa Monica’s mandatory wood-frame soft-story program applies to existing buildings that have the following characteristics:

Wood-frame construction
Built under building code standards enacted before November 10, 1980
Ground floor containing parking or similar open floor or basement space causing soft, weak, or open wall lines where there exists at least one or more floor levels above

Ordinance compliance for single-family homes is voluntary. Buildings which have already completed all required seismic retrofit work prior to the adoption of this ordinance, with lateral load resisting analysis, structural design plans, and valid final approval from the City of Santa Monica, are exempt from the ordinance requirements. However, previously retrofitted buildings with the following characteristics are subject to the ordinance requirements despite previous retrofit work:

Buildings with pole structures supporting the soft, weak, or open front wall lines
Buildings of three or more stories with horizontal structural irregularities of Type 2, 3, 4, or 5 in ASCE 7-10 Table 12.3-1

In total, approximately 2,000 buildings in Santa Monica have been identified to fall within the scope of the City’s comprehensive seismic retrofit plan, including approximately 1,700 soft-story buildings. The inventory of wood-frame soft-story buildings has been made public by the Santa Monica Planning and Community Development Department.

Building Owner Noticing Schedule

Implementation of the Santa Monica wood-frame soft-story ordinance was carried out in phases. The timeline for compliance for each unique structure began following distribution of the Order from the Building Official. Orders were issued between September 2017 and July 2018 according to priority levels determined by the number of residential units in each soft-story building.

Timeline

The original retrofit timeline implemented in 2017 (shown below) has been revised by the City of Santa Monica. Projects with a pending application as of March 13, 2020, or submitted between March 13, 2020 and the expiration of the COVID-19 emergency are entitled to a two-year extension to all applicable compliance dates. An updated compliance date schedule is available here.

Original compliance timeline	milestone
BEGIN PROCESS	Service of the Order to the Building Owner
2 YEARS AFTER ORDER	Deadline to submit structural evaluation report
3 YEARS AFTER ORDER	Deadline to submit application for building permit and plans
6 YEARS AFTER ORDER	Deadline for final approval

In the News

LA Times: Santa Monica Adopts Nation's Most Extensive Earthquake Retrofit Plan

LA Times: Santa Monica Offers L.A. a Cautionary Tale on Quake Vigilance

Infographic: Look at How Apartments Can Collapse During an Earthquake (LA Times)

CONTACTS

Wiss, Janney, Elstner Associates, Inc.
Phone: (626) 696-4650
E-mail: seismicordinances@wje.com

City of Santa Monica Building and Safety Division | Community Development Department
1685 Main Street, Santa Monica, CA, 90401
Phone: (310) 458-8355
Email: seismic@smgov.net