Expert Structural Seismic Retrofitting
High-resiliency engineering solutions for soft-story apartments, unreinforced masonry, and non-ductile concrete buildings to fulfill strict municipal ordinances.
What is a Seismic Retrofit?
A seismic retrofit is the structural modification and reinforcement of an existing building to significantly increase its resilience to tectonic forces. Older structures built before modern building code revisions often lack the lateral structural flexibility and strength required to survive high-intensity ground shaking. Seismic retrofitting introduces advanced lateral force-resisting elements such as steel moment-resisting frames, plywood shear walls, and foundation tie-downs, allowing the building to absorb and dissipate earthquake energy safely, preventing collapse and saving human lives.
High-Performance Retrofit Capabilities
Grading & Public Works Clearances
Expediting approvals for mass tract grading, hillside slope stabilization, B-Permits, and ADA right-of-way improvements.
Multi-Agency Coordination
Concurrent management of approvals across overlapping jurisdictions, including local Public Works, Caltrans, Fire Authority, and local Water Quality Boards.
Environmental & Hydrology Approvals
Navigating strict SWPPP (Stormwater Pollution Prevention Plan) and WQMP (Water Quality Management Plan) submissions through local and state environmental agencies.
Soft-Story Retrofit Engineering
Reinforcing open-front parking garages beneath wood-framed apartments using specialized steel moment frames to prevent ground-floor collapse.
Unreinforced Masonry (URM) Upgrades
Tying historic brick walls securely to floors and roof diaphragms utilizing heavy-duty tension anchors and shotcrete coatings.
Non-Ductile Concrete Reinforcement
Encasing brittle concrete columns in carbon-fiber reinforced polymer (FRP) wraps to increase structural shear capacity.
Other Civil Engineering Services
Retaining Walls Soldier Piling Structural Plans Seismic Analysis Structural Inspection Reports Temporary Shoring Steel Design Shoring Vaults Shotcrete Design Foundation Design Masonry Design Non-Ductile Retrofit Plans Unreinforced Masonry Upgrades Special Inspection Reports Structural Observations Foundation Observation Reports Permanent Shoring Deputy Inspection ReportClearing Mandatory City Safety Ordinances
Soft-Story Multi-Family Apartments: Designing low-impact steel frames that fulfill strict LADBS and local South Bay mandatory retrofit deadlines while preserving critical parking stalls.
Historic Commercial Retrofits: Modernizing legacy brick structures in old town districts, allowing commercial properties to satisfy strict seismic compliance without destroying historical street frontages.
Voluntary Residential Bracing & Bolting: Securing older single-family homes by bolting the wood mudsill securely to the concrete foundation and adding cripple wall shear bracing.
Our Path to Seismic Compliance
- Structural Feasibility & Plan Audit: We review the original structural layout and map the existing lateral load deficiencies.
- Computational Seismic Modeling: Running precision simulations to calculate exactly how the structure will displace and deform during a major earthquake.
- Retrofit Design Optimization: Selecting and positioning the most cost-effective structural steel or timber elements to meet local compliance metrics.
- Permitting & THA Clearance: Pushing the engineered drawings through rigorous municipal plan-checks to clear your building permit and stop pending city non-compliance fines.
Navigating Compliance & Regulatory Codes
Southern California cities, most notably Los Angeles, Santa Monica, and West Hollywood, enforce aggressive mandatory seismic retrofit ordinances with strict, legally binding deadlines. Failure to comply can result in recorded property liens, severe financial penalties, and revoked occupancy certificates. Our structural engineers design directly to Chapter 93 of the LA Building Code and ASCE 41 seismic evaluation standards, ensuring your project passes municipal plan-checks smoothly.
Seismic Retrofit FAQ
What is a soft-story building and why is it dangerous?
A soft-story building is a multi-story structure where the ground floor has large openings, typically for tuck-under parking or large retail display windows. Because the ground floor lacks solid shear walls, it is structurally weak and highly susceptible to completely buckling and collapsing under the lateral forces of an earthquake.
Will a seismic retrofit ruin the parking layout of my apartment building?
Poor engineering can. However, our structural team specializes in using space-efficient Steel Moment Frames. These frames add immense lateral strength around your open parking bays without blocking your stalls or reducing your parking capacity.
How long does a seismic retrofit project take to complete?
The engineering and plan-check phase typically spans 2 to 4 months depending on the city agency. The physical field construction can range from a few weeks to a couple of months, often executed with minimal disruption to existing tenants.
Integrated Engineering Solutions
A poorly executed seismic retrofit can inadvertently trigger major civil utility conflicts or structural load imbalances elsewhere in the building. Because The Eden Group unifies our Structural Engineering teams directly with in-house Civil Engineering and construction management assets, we design retrofits with a holistic approach. We ensure that installing heavy steel footings does not rupture main sewer or water connections, delivering a clean, constructible, and fully coordinated retrofit project.
Stop Non-Compliance Fines Secure Your Retrofit Set
Protect your real estate assets, safeguard your tenants, and satisfy all city mandates. Contact The Eden Group today for an authoritative seismic retrofit evaluation.