
ADU engineering for Los Angeles focuses on regional topography, county seismic and wildfire criteria, and unincorporated permit-path readiness. Permits are usually handled by city building departments in incorporated cities, and by Los Angeles County for unincorporated areas. Garage conversion ADUs in this county often involve slab assessment, wall retrofit scope, and upgrades to support habitable use.
Los Angeles ADU projects are engineered for county-wide hazard conditions, regional site variation, and unincorporated review pathways. Los Angeles County has one of California's most active ADU markets, driven by housing demand, multigenerational use, and rental cost pressure. Projects include detached and attached ADUs, garage conversions, and infill additions across both dense urban neighborhoods and suburban tracts.
Share a few project details and our engineering team will review your scope and guide you through permitting and design next steps.
After reviewing your project details, we'll provide a transparent quote the same day--typically within a few hours. Pricing varies based on project scope, complexity, and requirements.
We deliver complete structural permit sets. *If building departments have comments related to our scope, we handle all revisions--no extra fees, no limits.
See why homeowners and industry professionals trust us with their projects.
A garage adu involves garage conversion projects that transform existing garages into habitable units. California requires PE-stamped structural plans for every garage adu project.
Costs depend on project size, complexity, and site conditions. Our fixed-price quotes include:
• Structural calculations and PE-stamped plans
• Foundation and framing design
• Lateral system and seismic engineering
• Civil engineering coordination
Same-day quotes available — no hidden fees. Get a free quote for your Los Angeles County project.
Yes — California requires PE-stamped structural plans for every ADU. This covers foundation design, framing, and seismic compliance. This applies whether you're building in Los Angeles, Long Beach, Glendale, or unincorporated Los Angeles County.
Most Los Angeles County ADU plan sets are completed in 2–3 weeks — structural calculations, foundation design, framing plans, and civil coordination included. Rush service is available for urgent timelines.
We serve all cities in Los Angeles County including Los Angeles, Long Beach, Glendale, Pasadena, Torrance, Burbank, Santa Monica, West Hollywood, Culver City, El Segundo, Inglewood, and all unincorporated areas. Each city may have additional requirements, which we address in your plans.
Under California ADU law:
• Detached ADUs: up to 1,200 sq ft
• Attached ADUs: up to 850 sq ft
• Junior ADUs: up to 500 sq ft
Specific limits may vary by city within Los Angeles County. We size and engineer your ADU to the maximum allowed on your lot.
Most ADUs don't require additional parking. Parking is typically waived when the ADU is:
• Within 0.5 miles of public transit
• In a historic district
• A conversion of an existing garage
Check with your specific city for local rules.
Yes — garage conversions are one of the most popular ADU types, and you typically don't need replacement parking. Our engineering scope covers slab analysis, wall framing, ceiling structure, and seismic design for Los Angeles County garage conversions.
The City of LA supports online plan submittals through the LADBS Express ADU permitting program. Other cities within LA County have their own processes, many transitioning to digital. We deliver PE-stamped plans in PDF, ready for submission — all required sheets, calculations, and documentation included. We also handle every plan-check comment through final approval.
Yes. Our construction admin services include:
• Contractor RFI responses
• Submittal review
• Structural site observations
• Certification letters
This ensures your ADU is built to plan and code.

Get a free, no-obligation quote within 24 hours. Our experienced structural and civil engineers are ready to help with your residential or commercial project.
Trusted by 3,000+ homeowners and AEC professionals • Licensed in California State • 35+ years experience