Broad ADU construction
- Accessory building construction
- Construction management
The homepage covers broad ADU construction. This page remains the directory for the complete service set.
Services
ADU & Home Design-Build Services in Orange County
Custom ADUs, garage conversions, junior ADUs, in-law suites and more — designed, permitted and built by one licensed Orange County & Los Angeles team. Compare options with the California ADU cost guide and Orange County permit guide before requesting a quote.
Construction services and project paths
Start with the service group that matches your project. The linked pages explain the relevant planning path, and final scope is confirmed after a property review.
ADU design and documentation
- Architectural Drawings
- ADU Design and Build
- Permit Drawings
- Engineering Service
- Foundation Design
- Plan Drawings
- Schematic Design
- Shop Drawings
The ADU design-build page owns the coordinated process. Drawing and engineering work is prepared or coordinated as required for the property, approved scope and permit review.
Custom ADU
- Custom ADU
Custom ADU planning starts with the lot, use, privacy, utilities, design direction, permit path and construction scope for the specific property.
Garage conversion
- Garage Conversion
Garage conversion planning starts with the existing structure, access, parking, utilities and jurisdiction feasibility before the construction scope is set.
Backyard cottage
- Backyard Cottage Construction
Backyard cottage planning follows the detached ADU path, with footprint, access, utilities, privacy and style reviewed together.
Custom home and new construction
- Home Additions
- Custom home building
- New building construction
- Build A New Home
- New Construction
For qualifying home-addition, custom-home and ground-up residential inquiries, start with this services directory. Project scope and fit must be confirmed for the specific property.
ADU type and guide pages
Custom ADUs
Designed around your lot, family and budget.
Detached ADUs
A standalone backyard home planned around footprint, privacy, utilities and permit path.
Attached & Above-Garage ADUs
Shares a wall or sits above the garage when space is tight.
Garage Conversions
Turn your existing garage into a legal, rentable unit.
Junior ADUs (JADUs)
A compact unit up to 500 sq ft within your home.
Granny Flats
The everyday ADU for family or rental income.
In-Law Suites
A private, accessible suite for multigenerational living.
Backyard Cottages
A cottage-style detached ADU with character.
ADU Floor Plans
Layout ideas by size, then a custom plan for your lot.
The Complete ADU Guide
Types, cost, timeline and permits — start here.
ADU Contractor in Orange County: Design, Permits & Construction
L Square Construction is a licensed ADU contractor serving Orange County and Los Angeles. We coordinate feasibility, design, engineering, permits and construction with one point of accountability. Review the ADU design-build process, then compare a custom ADU with a garage conversion ADU before requesting a property-specific scope.
Real project examples
Real ADU build examples from the Orange County & Los Angeles area
Browse L Square ADU work across multiple completed examples, including exterior details, interiors and finish inspiration.
View real ADU construction examples
Why build with L Square
Design, permits and construction under one roof. L Square is a licensed Orange County design-build team (CSLB #1095476). One contract covers architecture, engineering, city approvals and our own build crews — so your ADU moves on a fixed schedule from first drawing to final inspection, across Orange County and Los Angeles.
- 01 · Architect-grade design
- Every unit is drawn around your lot, light and privacy.
- 02 · Permit-ready, OC-savvy
- We know each city’s ADU rules and clear the approvals for you.
- 03 · Built once, built right
- Our own crews deliver on a fixed schedule, foundation to finishes.
Licensed · Insured · Bonded · CSLB #1095476 · Orange County & Los Angeles
Building an ADU in your Orange County city
ADU rules vary by city — we handle the specifics for your address. Statewide, California allows ADUs up to about 1,200 sq ft with 4-ft side and rear setbacks (CA HCD); your city may add its own details. For the statewide rules, see the CA HCD ADU Handbook.
Related guides & articles
ADU cost guide (2026)Honest ranges by type + the 7 things that move the price.
California ADU laws 2026What changed this year for Orange County homeowners.
OC permit requirementsSubmittals, fees and inspections, city by city.
How long does an ADU take?Real timelines by phase — design, permits and build.
Casita vs ADUWhat the words mean and how it affects permits.
Is an ADU worth it?Rental income, resale value and the real ROI.
How to hire an ADU contractorThe CSLB check and what to look for before you sign.
What is an ADU?ADU meaning, the four types, and why California made them easy.
Above-garage ADUThe apartment over the garage — height rules and the structural truth.
Prefab vs custom ADUWhat factory prices leave out, and which lots favor which path.
SB 9 vs an ADULot splits explained — and why the ADU usually wins.
Building an ADU in Los Angeles?How LA & LADBS differ — our LA design-build hub.
Ready to start
your ADU?
Get a free, no-pressure quote from a licensed Orange County design-build team — and a plan drawn around your lot.