ADU Alliance

50 Frequently Asked Questions About ADU

Let’s Delve into 50 Frequently Asked Questions about ADU

As a homeowner in Orange County, you might have heard about Accessory Dwelling Units (ADUs). They are becoming a popular home addition across California, but with this new trend comes a lot of questions. The ADU Alliance is here to answer the 50 most frequently asked questions about ADUs.

50 Frequently Asked Questions About ADU


Q: What is an ADU? 

A: An ADU, or Accessory Dwelling Unit, is a secondary housing unit on a single-family residential lot. It can be attached to the primary house, a stand-alone structure, or a conversion of an existing space like a garage. Learn more about what is an ADU in Orange County, CA.

Q: Did the State laws recently change with regard to ADUs? 

A: Yes, California has made several legislative changes to ease restrictions and promote the construction of ADUs.

Q: Why are California homeowners building ADUs? 

A: Many homeowners build ADUs as a means of earning rental income, providing a home for a family member, or increasing their property value. They also contribute to addressing the housing shortage in California.

Q: Why are ADUs becoming so popular? 

A: With changes in state laws making it easier to build ADUs, coupled with their potential benefits, their popularity is on the rise.

Q: What kind of ADUs are there? 

A: There are several types of ADUs, including attached ADUs, detached ADUs, garage conversions, and Junior ADUs (JADUs). You can find more details on our services page.


Q: What kind of property qualifies to build an ADU?

A: Generally, most single-family or multifamily residential lots qualify for an ADU. For specific guidelines and restrictions, visit ADU regulations.

50 Frequently Asked Questions About ADU in orange county

Q: Is there a minimum lot size necessary to build an ADU on your property?

A: No, California law does not prescribe a minimum lot size to build an ADU. However, local zoning and building codes may have specific requirements.

Q: Where on my property can I build an ADU?

A: You can build an ADU in your backyard or convert an existing structure like a garage. Check out our backyard ADU and garage conversion services.

Q: What size ADU can I build? 

A: The size of your ADU can vary based on your lot size and local regulations. For more specific details, contact our ADU consultation service.

Q: Do I have to provide parking for an ADU?

A: Not necessarily. Parking requirements can vary based on the location of the ADU and proximity to public transit. Visit our ADU regulatory assistance page for detailed information.

Q: Can I rent an ADU to a tenant?

A: Yes, you can rent out your ADU. This can be a great way to generate additional income. Learn more about ADU for rent in Orange County.

Q: Can I sell an ADU without my house?

A: No, ADUs cannot be sold separately from the primary residence.

Q: Must I live on the property?

A: Yes, typically one of the units (the main house or the ADU) must be owner-occupied.

Q: Do ADUs require pedestrian access from the street?

A: Some localities require separate access to the ADU from the street, but not all.

Q: Can I build an ADU on a duplex, triplex, or other multifamily property?

A: Yes, under new state laws, you can build an ADU on a property with a multifamily dwelling. Learn more about ADU apartments.

Q: I have a unique property or situation, where can I get advice to determine if I qualify to build an ADU?

A: Our ADU consultation service is the best place to start.

Q: What is a JADU?

A: A Junior Accessory Dwelling Unit (JADU) is a smaller living unit (up to 500 sq ft) within the walls of an existing residence. More information on JADU garage conversion can be found on our website.

Q: Can I build both an ADU and JADU on my property?

A: Yes, under new state laws, you can build both on a single-family lot.

Q: Can my Homeowners Association stop me from building an ADU?

A: No, Homeowners Associations cannot prohibit the construction of ADUs, as per state law.

Q: Can I still convert my garage into an ADU if it is located less than 4 feet away from my property line?

A: Yes, as per state law, you can convert a garage into an ADU even if it’s located less than 4 feet from the property line. Check out our garage ADU conversion service for more details.

Q: Where do I start if I want to consider building an ADU?

A: The best place to start is by booking an ADU consultation with us at ADU Alliance.

ADU COSTS50 frequently asked questions about adu

Q: How much does it cost to build an ADU?

A: The cost of building an ADU varies widely, depending on factors like size, location, materials used, and design complexity. Our ADU construction service can provide a more detailed cost estimate.

Q: How much does an architect charge for ADU plans?

A: Architect fees can also vary widely. At ADU Alliance, we offer affordable ADU architecture services tailored to your specific needs.

Q: What kind of city fees do I have to pay to build an ADU?

A: City fees can include building permit fees, impact fees, and utility hookup fees among others. Our ADU regulatory assistance can help you navigate these fees.

Q: Are there ways to save costs when building an ADU?

A: Yes, cost savings can be realized through efficient design, choice of materials, and even the type of ADU. Our ADU consultation service can help identify cost-saving opportunities.

Q: Are there ways to finance the costs of an ADU?

A: Yes, various financing options are available, such as home equity loans, construction loans, and even some government programs. Explore more about ADU real estate for financing information.

Q: What are some ‘not so obvious costs’ of building an ADU?

A: Some less obvious costs include utility connection or upgrade costs, landscaping changes, and potential increases in property taxes. We discuss these in more detail in our ADU construction costs guide.


Q: How long does it take to build an ADU?

A: The timeline for building an ADU varies, depending on factors like project complexity, permit approval, and construction method. Our ADU construction page has more details.

Q: How is an ADU built?

A: An ADU is built much like any other home, with stages from planning and permitting through to construction and final inspection. See our ADU services for more information on the process.

Q: Are modular or pre-fab ADUs cheaper?

A: Modular or prefab ADUs can sometimes be more cost-effective than traditional construction due to their factory efficiencies. However, site preparation and installation costs can impact the total price.

Q: Is an ADU like a small house?

A: Yes, an ADU is essentially a small house, complete with its own living, sleeping, cooking, and bathroom facilities. Learn more about ADU apartments.

Q: Can I legalize an unpermitted Accessory Dwelling Unit or garage conversion?

A: Yes, unpermitted ADUs or garage conversions can often be legalized by applying for the necessary permits and meeting building code requirements. More details can be found on our ADU regulatory assistance page.

Q: Can I connect ADU utilities to the existing home?

A: Yes, utilities for the ADU can typically be connected to the existing home’s systems, though some jurisdictions may require separate connections.

Q: Can I build an ADU above my existing garage?

A: Yes, it’s possible to build an ADU above an existing garage, depending on local zoning and building codes. We offer services specifically for above garage ADUs.

Q: Where can I get a construction checklist of what items go into building an ADU?

A: Our team at ADU Alliance can provide you with a comprehensive checklist during our ADU consultation service.

Q: Can I have separate utility meters for the ADU?

A: Some jurisdictions do allow for separate utility meters for an ADU, but others may not.

Q: What improvements do I have to make to my garage to convert it into an ADU?

A: Garage conversions typically require adding insulation, heating, cooling, plumbing, and proper egress, among other improvements. See our garage conversion ADU service for more information.

Q: What’s the best way to find an ADU contractor?

A: A great starting point is to consult with us at ADU Alliance. As the best ADU experts in Orange County, we can help connect you with experienced contractors.


Q: Does building an ADU on a single-family property make my home subject to rent control?

A: Rent control policies vary by location, and an ADU may or may not be subject to these laws. Check out our ADU regulatory assistance page for guidance.

Q: Will my property tax go up if I build an ADU?

A: Building an ADU can increase your property value, and it may result in an increase in property taxes. More details can be found on our ADU costs page.

Q: If I have DWP power lines at the back of my property, where can I build an ADU?

A: This depends on local regulations and safety considerations. Our ADU regulatory assistance service can provide guidance specific to your property.

Q: Is building an ADU a good investment?

A: Yes, ADUs can be a great investment, adding value to your property and providing potential rental income. Learn more about ADU’s investment potential.

Q: Where can I find more resources about building an ADU?

A: Our ADU resource center offers a wealth of information on ADUs, from planning to construction.

Q: Can my ADU have a separate address and mailbox?

A: This varies by local regulations, but in many cases, ADUs can have a separate address and mailbox.

Q: How large should I make my ADU?

A: ADU size depends on your needs, property size, and local regulations. Learn more about ADU sizes on our ADU apartments page.

Q: How do I ensure that the ADU & main home maintain their own privacy?

A: Good design is key to maintaining privacy. Consider factors like window placement, landscaping, and separate entrances. Our ADU design service can help.

Q: Are ADUs good for seniors and retirees?

A: Yes, ADUs can provide a great solution for seniors and retirees, allowing them to live close to family or generate rental income. See our ADU for seniors page.

Q: Does building an ADU turn my property into a duplex?

A: No, an ADU does not typically turn a property into a duplex. An ADU is a secondary dwelling unit on a single-family property.

Q: Are ADUs good for first-time buyers in California?

A: Yes, ADUs can offer extra income potential that can help offset mortgage costs. More on this at our ADU for first-time buyers page.

50 feequently asked questions about adu

Q: What kind of appliances do I put in an ADU?

A: This depends on the size and design of the ADU, but generally, you can put any appliance that you would in a standard home. More about this is in our ADU interiors section.

These are 50 frequently asked questions about ADU and If a homeowner has a question that isn’t addressed in this list, they shouldn’t hesitate to reach out to us at ADU Alliance.

We understand that every homeowner’s situation and property are unique, and we’re committed to providing personalized advice and solutions. They can get in touch with us directly via our Contact Us page, or book a detailed ADU consultation.