Get started with the ADU process

The ADU Process

For the most accurate and up-to-date information, please also contact your local Planning Department to discuss your project.

  1. Think about what you want

    Visit our Standard Plans Program to look at floorplans and save time and money on design and permitting. You can also learn about your local ADU rules, use the Address Look-Up Tool to find out what you are eligible to build and estimate costs or rents using the ADU Calculator.

  2. Talk to a Professional

    Get an ADU Feasibility Consult from us or contact your local planning department to find out in advance about any special issues with your property.

  3. Make a Sketch

    Make a sketch of our property, including existing home, any other structures and proposed ADU. Use the exercises in our ADU Workbook to complete.

  4. Get a Planner’s Advice

    Now that you have a better idea of what you want to build, bring your sketch in. A planner will advise you on what rules might apply to your proposed ADU and what to consider.

  5. Hire Experienced Professionals

    Although you can build an ADU as an owner builder, we recommend hiring a licensed architect or designer to design your ADU and a licensed builder to construct it, or a design/build team for the entire process. Whoever you hire will help with the application process.

  6. Prepare Application Package

    Your professional team will be instrumental in preparing the Permit Application. Check out our on-demand webinar on permitting in our webinar library. We also recommend asking for a pre-application meeting with your planning and building department before formally submitting plans.

  7. Submit Application Package and Pay

    Check your local ADU rules and processes to learn how your city or county fees are assessed, how and where to submit/pay, and any documents that need to be submitted like other agency permits.

  8. Get Permit Issued

    Jurisdictions have up to 60 days to review your complete application. They may have comments for you and vour team to respond to. Once your application is approved and fees are paid, you can collect your building permit.

  9. Construct ADU

    Check-in regularly with your builders or design/build team and make decisions about materials as needed. Timelines for construction vary, but 12-18 months is fairly common.

  10. Schedule and Pass Inspection

    Your builder will schedule a final inspection as construction concludes. Once your ADU has passed, your ADU is ready for move-in!

Take the first steps toward building your ADU

Now that you know you’re allowed to build and have set a budget, here’s everything you can expect once you begin building your ADU.

Complete the prep-work checklist

Before moving forward, you’ll want to make sure you’ve completed the following preliminary steps:

Decide your approach: prefab or custom build

Often people hire an architect or designer to design a ADU and then a builder to provide additional cost information and to ultimately construct the unit.

Some homeowners hire a design/build team that handles the entire project, including both the design and the construction, while others work with a modular home company. Selecting your team involves looking at their past work of a similar scale and checking references. It can also be helpful if they have worked in your community and know the local permitting process.

Prepare for working with your designer

When designing your ADU, you will consider size, use, layout, specific project needs (storage, laundry room, etc.), architectural style, and privacy.

Once you have a preliminary design, it’s a good idea for you and your designer to have a pre-application meeting with the local planning (and possibly building) staff. At that meeting, you can ask questions and address any critical issues prior to submitting your permit application. You will also review all requirements, fees, and other considerations specific to your property and project and any unique requirements not previously considered.

Explore neighborhood ADUs

Be prepared

Our goal is to help you feel prepared and work effectively. Learn more about what to expect in the ADU building process below.

Permits and working with the city

To apply for permits, you and your project team will need to complete the forms required by your jurisdiction and provide detailed drawings and other documentation. The City will provide comments on your application that you will need to address and resubmit for approval. Most projects require 1-3 rounds of revisions working with city staff. Once your application is approved and all fees are paid, you will be issued permits to start construction.

Preparing for construction

Now that you have your building permits, you can start construction of your ADU. The builder you hire will lead this step. Communicate frequently with your builder, and verify progress before making payments. During construction, your ADU will be inspected multiple times to ensure it is being built according to the permitted plans. When all the work is complete, a building inspector will conduct a final inspection. Upon approval, you will receive a Certificate of Occupancy and possibly a registration letter for your new ADU.

Download ADU workbook

Becoming a landlord

Construction is complete, and now it’s time for someone to move in. This may be you, a friend, a family member, or a renter.

If it is a tenant, there are plenty of resources to help you if you are a new landlord, including organizations that can match you with a renter and help you manage your unit. You may want to consider pricing the unit so a community member can move in.

Learn more

Determine what you’re eligible to build

Good news: New state laws make it even easier to build an ADU or Junior ADU. Check out your local ADU rules to learn more!

Once you’ve determined what you’re eligible to build, contact your city to double-check your assumptions and to seek clarity on rules.

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As a social enterprise, HPP CARES CDE has achieved significant and wide-ranging accomplishments in recent years. Working under the National Coalition for Equities' (NCFE) umbrella, our focus has been on advocating for a strong community voice among federal and state regulators and major private sector corporations. We've dedicated ourselves to addressing public policy issues, particularly those related to wealth and income inequality impacting affordable homeownership and small business growth.

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