Wood-Frame Soft-Story Structures
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To update the outdated ordinance, the city of Santa Monica passed a comprehensive seismic retrofit program on March 28, 2017.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.
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 will be carried out in phases. The timeline for compliance for each unique structure begins following distribution of the Order from the Building Official. Orders will be issued according to priority levels determined by the number of residential units in each soft-story building. The noticing schedule is available here (updated August 2017).
The city of Santa Monica requires that wood-frame soft-story building retrofits adhere to the timeline shown below. The timeline for each building type is initiated following service of the Order to the Owner. Orders will be delivered according to the phases outlined above.
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
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