Southern California's Trusted ADU Builder
Hexagon is the ADU builder San Diego and Los Angeles homeowners rely on. We specialize in designing and building accessory dwelling units that unlock property value, provide flexible living solutions, and maximize your investment.
Generate substantial passive income while retaining full property ownership.
Add hundreds of thousands to your property value with a well designed ADU.
Create space for aging parents, adult children, or extended family while maintaining privacy.
Streamlined permitting for ADUs under recent California legislation.
ADU Types We Build
From detached units to garage conversions, we design and build the perfect ADU solution for your property.
Detached ADU
Stand-alone units offering maximum flexibility and privacy. Perfect for rear yards or corner lots.
Attached ADU
Units connected to the primary residence, maximizing land efficiency and shared utilities.
Garage Conversion ADU
Convert existing garages into functional living spaces. Quick timelines, proven design.
Two-Story ADU
Maximize unit size with two-story designs. Modern architecture, efficient layouts.
Our ADU Building Process
A systematic approach to designing and building your perfect ADU.
Consultation
We meet with you to understand your vision, budget, and ADU goals. Initial feasibility assessment begins.
Site Review
Detailed property analysis. Zoning review, soil testing, utility assessment. Everything needed for informed design.
Design + Engineering
Custom ADU design tailored to your property. Structural engineering, mechanical systems, aesthetic vision.
Permitting
We handle all permit applications and approvals. Building department coordination, expedited processing.
Construction
Manufacturing begins while permits process. On-site assembly, inspections, quality assurance throughout.
Completion
Final walkthrough, address any punch list items, certificates of occupancy. Your ADU is ready to use.
Off-Site Built. On-Site Perfected.
We fabricate ADU components in our facility, then assemble on-site or deliver them completed, ensuring precision, speed, and quality control that traditional site-built units cannot match.
30 to 40% quicker than traditional site-built ADUs.
Factory precision meets onsite expertise.
Built indoors, no rain delays.
Less noise, dust, and neighborhood impact.
Know exactly when your ADU arrives and is completed.
Engineered for California
Every ADU we build meets the highest standards for resilience, safety, and sustainability in Southern California's climate.
Fire-Resistant Design
Fireproof materials, Class A rated components, and wildfire-ready construction standards.
High R-Value Insulation
Superior thermal efficiency reduces energy costs year-round in any climate zone.
Steel Frame Construction
Durable, resistant to seismic activity and California earthquakes. Built to last.
Low-Maintenance Materials
Premium finishes require minimal upkeep. Spend less time maintaining, more time enjoying.
Solar-Ready Roof Design
Built-in preparation for solar panel installation. Maximize energy independence and ROI.
Low Carbon Footprint
Offsite manufacturing minimizes waste. Sustainable design reduces environmental impact.
High Acoustical Value
Sound-dampening materials create peaceful, quiet interior spaces.
Weather-Resilient
Designed to withstand coastal winds, water intrusion, and extreme weather conditions.
Offsite Modular ADU Timeline
Our offsite manufacturing approach dramatically reduces your ADU timeline.
Design + Permits
4 to 6 Weeks3D design, engineering, and permit processing run simultaneously.
Factory Build
6 to 8 WeeksYour ADU is manufactured in our controlled facility while site prep happens in parallel.
Site Assembly
2 to 4 WeeksPrecision onsite assembly of factory-built modules. Minimal disruption to your property.
Final Touches
1 to 2 WeeksUtility connections, landscaping, final inspection, and key handover.
Areas We Serve
San Diego
Los Angeles
Can Your Property Support an ADU?
Get a free ADU feasibility assessment. We will evaluate your property and tell you exactly what is possible.