ADU Construction

Accessory dwelling unit design & build services in Redwood City & the greater Bay Area

Accessory Dwelling Units (ADUs) add a complete living space to your home, with a kitchen, bathroom, bedroom, and living room. What that space looks like depends on what you need from it and how talented your designer is. We offer outstanding design and construction services that can make your ADU a phenomenal space perfectly attuned to your needs. With high standards, detail-oriented work and the mission to make your construction project as smooth as possible, we’re the ideal construction company to work with in the Bay Area. Learn more about our team and ADU builders below.

Exterior of new accessory dwelling unit built in Redwood City, California

What is an ADU?

An Accessory Dwelling Unit (ADU) is a self-contained living space that is typically located on the same property as a primary residence. ADUs are also known by various other names, including “in-law apartments,” “granny flats,” “secondary suites,” or “casitas.” These units are designed to be independent and provide living accommodations separate from the main house, often with their own entrances, kitchens, bathrooms, and living areas.

ADUs can take various forms, such as converted garages, standalone cottages, basement apartments, or additions to the primary residence. While most of the units our ADU builders develop are standalone structures, junior attached ADUs and garage conversions are also popular. 

Craftsman style ADU built in Menlo Park with pale blue exterior paint and white trim

How People Use ADUs

Every home and family are a little unique and need something different from their ADU. However, there are some common uses of ADUs which make modern life more practical, joyful and even more affordable.

  • Rentals: Passive income is possible without owning a second property. ADUs are perfect rental units.
  • Granny flats: Your in-laws or your own parents can live with you, even if just for part of the year, in an ADU.
  • Teenager space: Those with teens know how much they benefit from their own space.
  • Entertaining space: Invite friends and family over and never have to ask them to get a hotel room.
  • Work space: Those who own their own business or side hustle can work from an ADU and even meet clients in them.
  • Extra living space: Sometimes, you just want more for yourself.

No matter how you plan to use your ADU, our ADU experts will ensure that yours exceeds all state and local requirements. Our thoughtful ADU design can incorporate features based on your intended use, while remaining flexible enough to serve multiple purposes over time. After all, today’s work space or guest house might be tomorrow’s rental property.

See Our Latest ADU Projects

What Goes into ADU Design?

Determining what you need for your space and your budget are the two first steps in ADU design. We help you envision the space and understand how far the typical budget can go. ADUs are small, which means that many people can afford high-end materials or features they would not be able to afford in a full-sized home. Or, you may want to keep your choices more moderate and make the project more affordable. We can work with you either way.

The most enjoyable part of the process for you might be picking out all of the colors and fixtures for your new space. It’s many homeowners’ dreams to create a living space from scratch which conforms to their style specifically. On our end, we’ll pay attention to your wants for the fun aspects of the space and make sure that the more boring details are still high-quality. That includes things like the plumbing, HVAC and electrical systems. Most homeowners don’t have preferences for these, but we make sure that they meet or exceed the quality of your current home.

hallway in an ADU with skylight and hardwood flooring
an ADU construction finished by our team

ADU Building Regulations

One of the advantages of working with experts on your ADU design & build is that you don’t need to worry about if your build will follow regulations

We have complex ADU building codes in California, with one set at the state level and then another depending on your specific municipality within the Bay Area. We handle the process of making the design conform to the rules and getting the permits and inspections your ADU needs to be legal for yourself and for others.

What is Required to Build an ADU in Redwood City, CA?

Redwood City has many requirements for new ADU construction. Some of them are consistent with the rest of the state, while some of them are unique.

  • Minimum 850 square feet for a one-bedroom ADU, or 1,000 square feet for an ADU with more than one bedroom.
  • Short-term rentals of new ADUs or JADUs are not permitted.
  • No impact fees are charged on ADUs less than 750 square feet.
  • Attached ADU shall not exceed fifty (50) percent of the main dwelling’s total square footage and must meet height standards for the underlying zoning district.
  • Prior to occupancy, a new address shall be required for all ADUs and JADUs at a fee of $152

These regulations are still changing, so the best way to get up-to-date information is to speak with one of our ADU experts. You can also learn more at

Serving Redwood City & More

Our ADU construction team is proud to service the greater South Bay and peninsula, including Redwood City, Menlo Park, San Carlos, and more.

See our full service area or call now to learn more.

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