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A Step by Step Process to ADU Remodeling in California

23 July

Remodeling an Accessory Dwelling Unit (ADU) in California doesn’t have to be a difficult process. In this guide, we’ll take you through a step-by-step process on how to effectively remodel your ADU. But first, let’s define what an ADU is.


What is an ADU? 

An Accessory Dwelling Unit, or ADU for short, is a secondary housing unit that exists on a property that’s zoned residential. It can be detached from the primary house, attached, or even part of the existing primary house.


How to Remodel an ADU:

Now that we have an understanding of what an ADU is, let’s focus on the step-by-step process to remodel an ADU.

Step 1: Planning 

Determine the extent of the remodel: Includes considering the available space, the purpose of the ADU, and the budget.

Draft a timeline: The planning step commonly takes around 2 to 4 weeks. 

Step 2: Designing

Hire your team: You need to work with a professional who understands the local codes and regulations.

Designing the remodel: The team will help you design the remodel based on your needs, wants and the property’s constraints. This process can take about 1 to 1.5 months.

Step 3: Secure Permits

Submit your design for permits: Your team can help submit the necessary documents for permits which can take around 1 to 3 months.

Step 4: Construction

Find a reputable contractor: If your team doesn’t provide building services, you’ll need to find a contractor.

The construction phase: Depending on the complexity of the remodel, construction can take 2 to 6 months.

Step 5: Inspection 

Final inspections are conducted: Once your ADU remodel is complete, it must pass a final inspection to declare the property safe and habitable. This usually takes a few days to a week.


Although the above is a general how-to guide, there are still several factors that can influence the timeline and steps to remodel an ADU, such as:

Property constraints: The size, location, and current condition of your property can dictate how much you can change.

Legal regulations: Depending on your city or county, there may be specific regulations or zoning restrictions related to ADUs.

Budget constraints: The overall cost can greatly affect the scope and timeline of the project. Having a flexible budget can make the process easier.

Contractor availability: Renovation timeline also depends heavily on the contractor’s schedule and availability.


In conclusion, remodeling an ADU is a complex process, but with careful planning, it can be carried out smoothly. Be sure to consider all the above factors to ensure a successful and efficient remodel. Remember to keep communications clear with your hired professionals, and always keep on top of your project’s progress. With enough research, patience, and diligence, you’ll be able to achieve your dream ADU remodel in California. Happy remodeling!

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