In 2015, Ordinances 183893 and 184081 were passed by the city of Los Angeles, California. These ordinances focus on retrofitting old buildings so that they are better able to cope with the seismic threats that regularly plague the state of California. Specifically, these ordinances covered buildings built before January 1st, 1978. These ordinances were issued under the Mandatory Retrofit Program.
The objective of this program is to safeguard specific types of buildings and their occupants against seismic incidents. The ordinances would ensure an improvement in structural durability and resilience while also reducing any underlying deficiencies.
There are an estimated 12,000 buildings that match the criteria set forth by the Los Angeles Mandatory Retrofit Program and its ordinances. The ordinances cover both “Soft Story” buildings as well as “Non-Ductile” buildings.
Soft Story Buildings:
A soft story building is quite a common structure. Any building with more than one story, that has windows, wide doors, openings or large spaces where a shear wall might be needed for structural strength is a soft story building. A typical soft story building could be one of the following:
● Retail buildings where the front fascia is constructed with glass
● Ground floor parking under wood framed apartments
● Multi-use buildings with large commercial spaces within and a tall 1st floor space (Malls, Cinemas, Office buildings etc.)
Clearly, these buildings have one or more structurally critical spaces that do not have the same level of reinforcement as the other floors or sections within the building.
Soft Story Retrofits:
The Mandatory Retrofit Program aims to help address the structural deficiencies of Soft Story structures. The program has come up with a set of criteria to assess which soft story structures in Los Angeles would require a retrofit. The criteria are as follows:
● Consist of 2 or more stories with wood frame construction.
● Built under building code standards enacted before January 1, 1978.
● Contains ground floor parking or other similar open floor spaces.
Additionally, the program implements a time constraint for the property owner to comply with:
● The property owner is expected to submit proof of previous retrofit, plans to retrofit or demolish within 2 years of the receipt of the Order to Comply.
● The property owner is expected to obtain a permit to start construction or demolition within 3.5 years of the receipt of the Order to Comply.
● The property owner is expected to complete construction within 7 years of the receipt of the Order to Comply.
The program does not apply to residential buildings with 3 or less units.
Non-Ductile buildings can be classified as any concrete construction made using the 1976 Building Codes. There are roughly 1,000 non-ductile buildings in the city of Los Angeles. While the buildings were built with reinforcing steel, the quality and construction levels of these buildings aren’t thorough enough to ensure that the buildings could survive a seismic shock. These older concrete buildings are built in such a way that the lateral force-resisting systems in place would not be able to sustain vertical and lateral loads in the face of an earthquake.
The two ordinances under the Mandatory Retrofit Program require concrete buildings that were constructed or planned before January 13th, 1977 to be assessed for seismic retrofitting.
The program implements a time constraint for the property owner to comply with:
● The property owner is expected to submit a completed checklist for review to determine if building is a non-ductile concrete building within 3 years of the receipt of the Order to Comply.
● The property owner is expected to submit proof of previous retrofit or plans to retrofit or plans to demolish building within 10 years of the receipt of the Order to Comply.
● The property owner is expected to complete construction within 25 years of the receipt of the Order to Comply.
Difference Between Ordinances:
There are a few key differences between the two ordinances under the LA Mandatory Seismic Retrofit Program. The highlights of each ordinance are detailed below:
Ordinance 183893 is concerned with the definition and compliance of buildings identified for the seismic retrofit program.
Specifically, Ordinance 183893 applies the retrofit requirement to:
● Buildings that have a wood-frame and were permitted or built before January 1, 1978.
● Buildings whose ground floor contain a parking space or other similar open /semi-open spaces.
● Building which contain four or more dwelling units.
Ordinance 183893 also prioritizes the identification and selection of buildings in the following manner:
● Priority I (Highest) - Buildings with 16 or more dwelling units. This priority has two sub-categories:
o 3 story and above – the orders were sent out to these buildings on May 2nd, 2016.
o 2 story – the orders were sent out to these buildings on July 22nd, 2016.
● Priority II - Buildings with 3 or more stories and contain less than 16 units. – The orders were sent out to these buildings on October 17th, 2016.
● Priority III - All buildings not falling within Priority I or Priority II
o Buildings with 9-15 units – the orders were sent out to these buildings on July 24th, 2017.
o Buildings with 7-8 units – the orders were sent out to these buildings on August 21st, 2017.
o Buildings with 4-6 units – the orders were sent out to these buildings on September 25th, 2017.
o Condos and Commercial units – the orders were sent out to these buildings on November 6th, 2017.
Ordinance 184081 is concerned with the Time Limits for Compliance for the seismic retrofit program.
Specifically, Ordinance 184081 applies the time limits compliance in the following manner:
● The owner is expected to submit structural analysis to demonstrate existing compliance within 2 years of receiving the order.
● The owner is expected to submit a structural analysis to demonstrate a proposed structural alteration to meet seismic retrofit requirements within 2 years of receiving the order.
● The owner is expected to submit the plans for demolition of the building within 2 years of receiving the order.
● The owner is expected to obtain all necessary permits for rehabilitation or demolition within three and a half (3.5) years after service of the order.
● The owner is expected to complete construction or demolition work under all necessary permits within seven (7) years after service of the order.
You Need to Retrofit if:
While this can all be quite confusing and if you feel like you might not need to consider a retrofit because it doesn’t match the criteria mentioned above, wait up! The ordinances only apply to wooden structure and non-ductile concrete structures for now. However, it is always wise to check if your building is earthquake ready and if a retrofit may be required.
The Department of Building and Safety has already identified the buildings that require a seismic retrofit in the city of Los Angeles and has sent out notices to each of the property owners requiring them to start work on their properties.
Contact & Conclusion:
Seismic retrofits are critical in ensuring human and public safety, especially with regards to older buildings. To know if your building, home or property requires a seismic retrofit, it is best to speak with experts from the industry or from The Department of Building and Safety. At Design Everest, we have you covered. You’ll have access to the best structural engineers, architects and project managers!
Call us at 877-704-5687 to get a free consultation and learn more about seismic retrofits in the city of Los Angeles and in the state of California and we can have the experts on our team help you!
*Note: The content published above was made in collaboration with members of Design Everest.
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