ADU Design & Engineering

Tailored ADU Design & Engineering Services

Liberty Design Group provides comprehensive, permit-ready ADU design and engineering services statewide in California. As your trusted partner, we deliver fast, affordable plans for junior ADUs, garage conversions, and detached units—all handled by licensed architects and engineers to ensure quick approvals, fewer city corrections, and schedules that stay on track for your projects.

We specialize in full-scope ADU solutions built specifically for California contractors. Our process starts with a detailed zoning and feasibility review, then moves into custom layouts that fit your site and client vision. We incorporate structural engineering, Title 24 energy compliance, plumbing and electrical layouts, and life safety details—creating builder-friendly drawings with real-world framing logic, clear dimensions, and construction sequencing to minimize field issues and change orders.

ADU design and engineering pricing options

Junior ADU (JADU ≤ 500 SF)

$5,000 (main home under 1,500 SF)

$6,500 (main home over 1,501 SF)

Includes zoning review, architectural plans, minor structural modifications, Title 24 coordination, plumbing/electrical layouts, life safety notes, permit-ready set. 2 design revisions + 1 city correction round.

Garage Conversion ADU

$6,500 (strict conversion)

$9,000 (conversion + addition)

Includes zoning analysis, architectural floor plans & elevations, structural engineering (foundation verification, shear walls, framing), Title 24, electrical/plumbing layouts, energy notes, permit-ready drawings. 3 revisions + 1 correction round.

Detached / Standalone ADU

$8,500 (0-800 SF, 1/2 stories)

$10,500 (801-1,200 SF, 1/2 stories)

Includes zoning & setback analysis, site coordination, architectural plans, structural engineering, Title 24, electrical/plumbing, energy compliance, permit-ready documents. 3 revisions + 1 correction round.

Common add-ons and third-party consultants

Topography & Engineering
Fire Protection & Utilities
HOA & City Permits
The process

Our ADU design & engineering process

01

Initial concept

Our first meeting focuses entirely on listening to your project goals, client needs, site constraints, and timeline priorities. We review zoning requirements, setbacks, height limits, and any local ordinances to confirm feasibility and identify the best ADU type—junior, garage conversion, or detached. This collaborative step establishes clear objectives and prevents costly revisions later.

02

Schematic design

We develop initial layouts, floor plans, and elevations based on our discussions. Options explore efficient space use, natural light, privacy, and integration with the main property. We present concepts that balance functionality (kitchen, bath, sleeping areas) with compliance, providing visual previews to align with your bids and client expectations.

03

Drawing and specification documentation

Detailed architectural plans take shape, coordinated with structural engineering for foundations, framing, shear walls, and load paths. We integrate Title 24 energy calculations, plumbing/electrical layouts, and energy notes. Every drawing includes precise dimensions, construction sequencing notes, and life safety details to support easy permitting and field execution.

04

Construction coordination and management support

We prepare complete permit-ready sets and submit on your behalf where possible. During plan check, we manage city comments, provide clarifications, and handle revisions promptly—keeping momentum high and avoiding delays that impact your schedule.

05

Final touches and approval

We finalize all documents, confirm full compliance, and deliver polished sets ready for your build team. The result is more than approved plans—it’s a reliable foundation that reduces change orders, protects your margins, and sets up successful ADU deliveries.

Our commitment to excellence

Superior Design

Our licensed team creates precise, buildable plans with attention to detail and real-world constructability.

High-Quality Compliance & Coordination

Every plan meets California standards, including Title 24 and local requirements.

Investment Value for Your Projects

Our efficient process helps you win more bids and scale ADU work profitably.

Best designers for ADUs

Our experienced architects and engineers work collaboratively from initial review through final approvals. We understand contractor realities—tight timelines, budget constraints, and the need for clear, field-ready plans—so we deliver documents that make your execution straightforward and reliable.

Explore the world of Minnaro Interior Design