Design

identify what you want in a design | understand the design process | hire and work with your design team

Project TIMELINE

Most ADU projects take 12-18 months to complete, but some extend to 24 months or more. The design process takes about 1-6 months, depending on the size, type, and complexity of your project.

Design FAQs

Here are a few of the most frequently asked questions about ADU design. See the content below and our ADU Guidebook for more guidance, resources, and tips for all steps of the process.

Most homeowners choose to work with some type of design professional to plan their ADU and help throughout the process. Bringing on a professional early in the process is often key to getting your ADU approved quickly, managed efficiently, and built cost-effectively. Relevant experience and fit will be critical.
There are a variety of types of designers, and they may be an architect, builder, “designer,” design/build firm, or a modular/prefab company. Start by asking friends, family, and neighbors for recommended architects, or use social media like Nextdoor or Instagram to search for local businesses and examples of their work. If you’re hiring a local individual or team, they’ll likely start the process by visiting your home and talking to you about your ideas and goals. If it seems like a good match, they will prepare a proposal detailing their services and fees. Professionals typically charge for an initial consultation or proposal.
See our Exercises for a list of questions to ask a potential architect or designer, our Glossary to be clear on terms, and our Guidebook for more details.
Although you can build an ADU as an owner-contractor, we strongly recommend hiring a licensed architect or professional designer and a licensed contractor, or a design/build team. In the long run, professionals end up saving you time and money on your project – without this professional help, you’ll likely spend a lot of money, effort, and time getting your project through permitting and construction. Most homeowners who have built ADUs say that hiring their team was the best money they spent throughout the entire process.
Once you have a design established with your architect/designer, it’s a great idea to discuss it with City staff so they can point out any issues before you prepare your application. You can visit the Permit Center during business hours or call or email to make an appointment.
This is also a good time to reach out to utility agencies (water, sewer, gas, etc.) to inquire about their infrastructural requirements and confirm connection and service fees. You can find more detail and contact information for relevant utility providers in the Guidebook.

Designing your ADU

Once you have a sense of what you want to build and what’s possible on your property and with your project budget, you can begin the process of designing your ADU, which starts with design inspiration and ends with permit-ready plans.

BEFORE you begin

It is helpful to have a clear sense of what you want early in the process. An architect or designer can help you brainstorm, but they cannot start designing until you’ve made fundamental decisions like the type of ADU you want (see Getting Started) and how many bedrooms it will have, etc. Our Exercises can help you think about these questions. For inspiration, you can learn about the types of ADUs you can build and explore example ADU Floorplans.

Hire Experienced Professionals

You can build an ADU as an owner-builder, but bringing on a professional early in the process is often key to getting your ADU project approved quickly, managed efficiently, and built cost-effectively. Relevant experience and fit are critical, and it’s important to look at their past work and check references.

Your team may include one or more of the following:

Licensed architect or designer to design your ADU and potentially see you through permitting and construction
Builder (also known as a contractor) to build your ADU
Design/build company that designs and builds your ADU
Modular/prefab company that sells preset designs for modular/prefab homes

Our ADU Exercises include a list of questions to consider when hiring a team, and our Guidebook provides an overview on design contracts and costs.

ADU Exercises

Local AIA Chapter

Create Initial Design

Once you have your team in place, you will work with them to design your ADU. Together you will consider size, use, layout, specific project needs (storage, laundry room, etc.), architectural style, and privacy.

Once you have an initial design, it’s a good idea to discuss it with City staff so they can point out any issues before submitting your permit application. Your design team can attend this meeting to clarify drawings and help you understand requirements.

If you haven’t already, this is also a good time to reach out to utility service providers (water, sewer, gas, etc.) to confirm your design meets their requirements. See the Directory in our Guidebook for all relevant contact information.