Navigating Local Permitting for ADUs in California
Building an accessory dwelling unit (ADU) is an exciting opportunity—but before construction begins, you’ll need the proper permits. California has made the ADU process easier in recent years, yet every city and county still has unique requirements. At MF ADU, we help homeowners understand and complete the permitting process efficiently so their projects stay on track.
Understanding Statewide ADU Regulations
California’s ADU laws are designed to encourage housing growth. They allow most single-family and multifamily properties to add at least one ADU, but specific limits can vary by city. State law sets the baseline, while local ordinances define details like maximum size, height, and parking requirements.
Key state provisions include:
Streamlined approval timelines (typically within 60 days)
No minimum lot size restrictions
Reduced or eliminated parking requirements in certain areas
Permission for both a detached ADU and a junior ADU (JADU) on one property
Step 1: Research Local Zoning Rules
Each city interprets state laws differently. Before you start, check local regulations for:
Maximum square footage and height
Setback distances from property lines
Utility connection requirements
Fire safety or environmental restrictions
We assist clients by reviewing local zoning maps and identifying what’s allowed based on the property’s size and neighborhood layout.
Step 2: Prepare and Submit Plans
Once the design is ready, we create detailed architectural plans, site layouts, and structural drawings for submission to the city. Prefabricated ADUs often speed up this step since their plans already comply with California’s building codes, reducing review times.
Step 3: City Review and Revisions
City officials review plans to ensure code compliance. Occasionally, they request clarifications or minor adjustments. Our team manages these revisions promptly to avoid unnecessary delays. Once approved, permits are issued for construction or installation.
Step 4: Inspections and Final Approval
After installation, city inspectors verify that the ADU meets all safety, energy, and accessibility requirements. Once inspections are passed, you receive final approval, and your ADU is ready for occupancy or rental use.
Did you know?
Did you know? California law requires cities to approve or deny ADU permits within 60 days—cutting the waiting period in half compared to traditional housing projects.
Simplifying the Process with MF ADU
Navigating local permits can be time-consuming, but with the right guidance, it becomes straightforward. At MF ADU, we handle the permitting process from start to finish, ensuring compliance with California’s evolving laws while keeping your project moving efficiently.
Explore our prefabricated ADU models to see how we simplify design, permitting, and construction for homeowners across California.
Frequently Asked Questions
How long does it take to get an ADU permit in California?
Most ADU permits are approved within 60 days if the application is complete and meets state requirements.
Do I need separate permits for plumbing and electrical work?
No. These are included in the overall ADU building permit.
Can I start building before permits are issued?
No. Construction or installation can begin only after the city issues final building permits.
Do all cities in California follow the same ADU laws?
The state sets the baseline, but cities can adjust certain details like size limits and parking rules.
Does MF ADU help with the permitting process?
Yes. We handle the entire process—from plan submission to final approval—so you can focus on your vision, not the paperwork.