Natural disasters, particularly earthquakes, pose significant risks to buildings and their occupants. One of the most vulnerable building types during seismic activity is a soft story structure—a multi-story building with a weak or flexible lower level, often featuring large openings such as parking garages, commercial spaces, or large windows. To address these risks, many cities have implemented Soft Story Ordinances, requiring structural retrofitting of these buildings to improve their resilience against earthquakes.
What is a Soft Story Ordinance?
A soft story ordinance is a law or regulation enacted by municipalities to identify, evaluate, and strengthen soft story buildings that are susceptible to collapse during an earthquake. The goal is to enhance the structural integrity of these buildings, reducing the risk of fatalities, property damage, and displacement of residents.
Key Elements of Soft Story Ordinances:
- Building Assessment: Cities identify buildings that meet the soft story criteria and require property owners to conduct structural evaluations.
- Mandatory Retrofitting: Owners must retrofit their buildings to comply with modern seismic safety standards.
- Compliance Deadlines: Ordinances typically include deadlines for assessment, permit application, and completion of retrofitting.
- Financial Assistance: Some cities offer financial aid, tax incentives, or loan programs to help property owners manage the costs of retrofitting.
Why is Soft Story Ordinance Important?
1. Life Safety
Soft story buildings are at high risk of collapse during an earthquake, endangering occupants and nearby pedestrians. Retrofitting reduces this risk and saves lives.
2. Property Protection
Seismic retrofits minimize structural damage, preventing costly repairs or total building losses in the event of a disaster.
3. Community Resilience
When buildings remain intact, residents can continue living in their homes, and businesses can resume operations quickly, reducing economic disruption.
4. Legal Compliance and Liability Reduction
Failure to comply with a soft story ordinance can lead to fines, legal liability, or forced building demolition. Compliance protects property owners from lawsuits and penalties.
Cities with Soft Story Ordinances
Several earthquake-prone cities have adopted soft story ordinances, including:
- Los Angeles, CA: The Soft Story Retrofit Program requires seismic strengthening of wood-framed soft story buildings constructed before 1978.
- San Francisco, CA: The Mandatory Soft Story Retrofit Program (MSSP) applies to pre-1978 multi-unit residential buildings with soft stories.
- Berkeley, CA: The Seismic Hazard Mitigation Ordinance mandates retrofitting of soft story buildings with five or more units.
- Oakland, CA: Similar to other California cities, Oakland requires retrofitting of soft story buildings under its local ordinance.
The Retrofitting Process
1. Initial Assessment
A structural engineer evaluates the building to determine whether it meets the soft story criteria and identifies necessary retrofits.
2. Design and Permitting
A retrofit plan is developed, including structural reinforcements such as shear walls, moment frames, or foundation strengthening. Property owners must obtain permits before construction begins.
3. Construction and Compliance
Retrofitting work is carried out according to approved plans, with inspections ensuring compliance with building codes and the ordinance.
4. Final Approval
After completing the retrofit, the city inspects and certifies the building’s compliance with the ordinance.
Challenges and Considerations
Cost of Retrofitting
Seismic retrofitting can be expensive, with costs varying based on building size, condition, and required upgrades. Property owners may seek financial assistance through grants, tax credits, or financing programs.
Tenant Displacement
Construction may require temporary relocation of tenants, posing logistical and financial challenges. Cities often provide guidelines to minimize tenant disruptions.
Enforcement and Penalties
Failure to comply with soft story ordinances can result in legal action, fines, or restrictions on property usage.
Conclusion
Soft story ordinances play a vital role in ensuring public safety, protecting properties, and enhancing community resilience against earthquakes. Property owners should take proactive steps to comply with local regulations and retrofit their buildings to meet seismic safety standards. While the process may require significant investment, the long-term benefits far outweigh the risks associated with inaction.