Los Angeles Non-Ductile Concrete Ordinance
In Los Angeles non-ductile concrete buildings are identified as having been constructed prior to the 1976 Los Angeles City Building Code provisions. 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 earthquake induced lateral displacements.
LADBS Ordinance No. 183893, states that the property owner must comply with the ordinance within the prescribed time limits:
3 Years from the date of the Order to Comply
Submit completed LADBS Checklist along with the supporting documents required by the checklist.
10 Years from the date of the Order to Comply
Submit one of the following:
- Proof of previous retrofit.
- Structural analysis and detailed plans showing full compliance with the retrofit ordinance.
- Plans to retrofit.
- Plans to demolish.
25 Years from the date of the Order to Comply
Complete construction and obtain a Certificate of Compliance.
Phases of Retrofitting
- Preliminary Building Checklist: The preliminary building checklist identifies the building as a potential non-ductile building and formally confirms whether it is in need of retrofitting
- Engineering: An extensive and comprehensive engineering process includes material and soil testing, structural analysis, schematic design, and calculation of the actual design for the retrofitting system itself, i.e. what is going to be done. There is a need to explore the seismic load capacity, mapping the reinforcement of the building and what the structural elements of the building are made of (floor system, column system, gravity load and more). After the analysis is complete, it is sent to the local municipality retrofit program for review.
- Construction: Once the local city approves the analysis, the execution of the actual construction can begin. How long the construction will take depends on a number of factors, including whether the building is vacant or not.
Requirements from Los Angeles Department of Building and Safety
If your building has been determined as a "Non-Ductile Concrete Building," you have within ten years after receiving an order to comply and submit a detailed evaluation of the building documenting whether the building meets or exceeds the requirements of Ordinance No. 183,893. The evaluation shall include one of the following:
- Proof that the building was previously retrofitted in conformity with the provisions in either Chapter 85 or former Chapter 95 (Ordinance No. 171,260; No. 179,324; No. 172,592; and No. 182,850) of the Los Angeles Building Code
- Proof that the building was previously retrofitted in conformity with the engineering requirements of this provision
- A report consisting of a structural analysis that shows the building meets the engineering requirements of this provision
- A report consisting of a structural analysis and detailed plans for the proposed structural alteration of the building to comply with the engineering requirements of this provision of Chapter-95 (Ordinance183893)
- Plans for demolition of the building