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ADU FAQs

Frequently Asked Questions about Accessory Dwelling Units (ADUs)

The ADU Universal Checklist will answer many of your questions about

  • Which lots qualify for an ADU
  • Setback, height, and fire requirements
  • Important considerations affecting your ADU plans

COST

  1. How will I know what the cost of the ADU Permit will be?
    Try our new Building Fee Estimator for a general idea of permitting costs.
    The size of your ADU will determine your building permit fees. See the Building Fee Schedule for fee information.
    In addition to the building permit fee, other fees may need to be paid before the City will issue your building permit.

    Applicants for an ADU may be required to pay:
  2. How might I save money on the construction cost of an ADU?

    Here are two potential options:

    • Units less than 750 sq. ft. will cost less to build, and in accordance with state law, as of Jan. 1, 2020, these smaller units are not subject to impact fees such as parkland and school fees.
        
  3. Will my property taxes increase if I build an ADU?
    Yes. Your taxes will increase based on the value of the ADU. Refer to the County Assessor’s website for more information.

  4. What if I already have an ADU but I want to sell it?

    If you are seeking to sell your ADU, you must first apply for a condominium conversion of the residence and ADU.
    See the ADU Condominium Conversions webpage for more information

  5. Can I build a new house and an ADU at the same time?
    Yes. There are rules to consider about the distance of the ADU to the main home. The new house must pass final inspection before a final inspection on the ADU can occur. 

 RENTAL PROPERTIES

  1. Can I build an ADU where the single-family house is a rental?
    Yes.

  2. Can I rent the house and ADU to different parties?
    Yes.

  3. Can I rent the ADU to whomever I choose?
    A homeowner has the right to rent their ADU to anyone they choose, however, you must comply with fair housing laws. You cannot establish discriminatory terms or conditions in the rental advertising or agreement. You cannot advertise or establish that the unit is available or not available to people of a certain race, color, religion, sex, handicap, familial status, or national origin, and you cannot refuse housing vouchers. Per state law, the minimum term for an ADU rental is 30 days, including for Airbnb rentals.

  4. Is an ADU required to have its own address?
    Yes. An address will be assigned to the ADU as part of the building permit process.

  5.  Is an ADU required to have separate utilities?
    No. Utilities can be combined with the main residence OR can be separate. The PG&E Building and Renovation Service Center has more information You can call them at  (877) 743-7782

  6.  Can an ADU have a porch? Does the porch count in the allowed square footage for the unit?
    ADUs may have a porch. If the porch is uncovered, it will not count toward the maximum floor area allowed. If the porch is covered and is 50% or more enclosed with walls, then it will count toward the allowable floor area of the ADU.

  7. How long does it take to get plans approved?
    It typically takes 20 business days to go through the first round of building review unless your plan needs additional review.  
    It is important to submit accurate and complete plans to stay within one or two plan review cycles.
    Generally, you will speed up your review process by following the instructions on the ADU Plan Review & Permit Process webpage and working with a professional who has experience with the City of San José permit process and ADUs.

  8. Is gas allowed for a detached ADU?
    The City has paused enforcement of its natural gas prohibition ordinance. You may utilize either natural gas or all-electric in your design.
    San José is a Climate Smart City and we encourage using all-electric infrastructure in new and remodeled construction to achieve the important goal of reducing greenhouse gases. For tips on electrifying your home, visit San José Clean Energy.

 

Got a question that isn't answered here? Visit our ADU Permit Process page, or the ADU Universal Checklist.

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