- Typical cost
- Scoped after an engineer's assessment
- Typical timeline
- 2–8 weeks for most single-family retrofits
- Permits through
- LA County Building & Safety
- Service area
- Altadena, San Gabriel Valley
What a Retrofit Involves
Bolting the house to its foundation and bracing the weak cripple walls under the floor so the structure moves with the foundation instead of sliding off it.
- Foundation anchor bolts and plates
- Cripple wall bracing with structural sheathing
- Hold-downs and shear transfer connections
- Soft-story steel moment frames for apartment buildings
- Chimney bracing or removal
Seismic Retrofit Conditions in Altadena
We do a lot of rebuild and repair work here, and the pattern is consistent: fire-hardened exteriors, upgraded defensible space, and a structure brought up to current code rather than restored as it was. Homes date largely from 1910 to 1950, so foundations are often unbolted, and slope and drainage matter on the upper streets closer to the mountains.
- Los Angeles County Building & Safety permits, not a city process
- Very High Fire Hazard Severity Zone materials and assemblies
- Fire rebuild and repair work brought fully up to current code
- 1910 to 1950 homes with unbolted foundations and original wiring
- Slope, drainage and brush clearance on foothill-adjacent streets
Soft-Story Ordinance Compliance
Los Angeles requires many wood-frame apartment buildings with tuck-under parking to be retrofitted. Those projects need engineered plans, permits and inspections, and there are deadlines attached to the order you received.
- Engineered plans for ordinance compliance
- Permit submittal and correction handling
- Phased work to keep units occupied where possible
- Sign-off documentation for the city
Why Engineering Comes First
We don't quote structural work off a walkthrough. A licensed structural engineer assesses the condition and specifies the fix, the plans go through plan check, and we build exactly to those plans with inspections at each stage.
- Licensed structural engineer on every scope
- Access and crawl-space evaluation
- LADBS permits and staged inspections
FREQUENTLY ASKED QUESTIONS
Do you do seismic retrofit in Altadena?
Yes. Altadena is part of our regular service area. We'll come out for a free on-site consultation, walk the property, and tell you what's realistic before you spend anything on design.
What does seismic retrofit cost in Altadena?
Scoped after an engineer's assessment. Site conditions in Altadena and your material selections move the number, which is why we price after walking the property rather than over the phone.
Who issues the permit in Altadena?
Permits for this work go through LA County Building & Safety. We handle the submittal, plan check corrections and inspections as part of the project.
How much does a seismic retrofit cost in Los Angeles?
It depends on the size of the house, the foundation type and how much access there is under the floor. Soft-story apartment retrofits cost considerably more because they need steel frames. We price it after an engineer's assessment.
Is a seismic retrofit required?
For most single-family homes it's voluntary but strongly recommended. For many wood-frame apartment buildings with tuck-under parking in Los Angeles, it's mandatory under the soft-story ordinance.
How long does a retrofit take?
Most single-family retrofits take 2 to 8 weeks of work once permits are issued. Soft-story building retrofits take longer and are usually phased.
Do you do seismic retrofits near me outside LA city limits?
Yes. We retrofit homes and soft-story buildings across Los Angeles County and surrounding cities within roughly 100 miles of Woodland Hills. Several cities besides LA, including Santa Monica and Pasadena, run their own retrofit ordinances, and we work under each city's program.
Similar Projects We've Built
Hillside Foundation Repair and Seismic Retrofit, Silver Lake
A 1926 hillside home that had settled several inches was underpinned with new caissons and grade beams, then bolted and braced to current standards.
Soft-Story Seismic Retrofit of a Long Beach Fourplex
A 1962 fourplex with tuck-under parking brought into compliance with a steel moment frame system, with all four units occupied throughout.
DISCUSS YOUR PROJECT WITH 1 SMART BUILD
Licensed, bonded and insured design-build general contractor serving Los Angeles County and Southern California. Tell us about your property and goals, and we'll walk you through feasibility, permitting and a clear plan.