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Accessory Dwelling Units
What is an ADU?
Accessory Dwelling Units (ADUs) are known by many names: granny flats, in-law units, backyard cottages, secondary units & more. Recently the State of California legislature has passed several bills in 2017, 2018 and 2019 to ease the creation of ADUs in areas zoned to allow single-family or multifamily use. ADUs can come in many shapes & sizes but are always a self-contained home that is smaller than the main house, and legally part of the same property. ADUs always contain a kitchen, bathroom, and a place to sleep. An ADU may be detached, attached, converted from existing interior space, converted from a garage, or built above a garage.
What is an JADU?
Junior Accessory Dwelling Units (JADUs) are units constructed from an existing legally permitted bedrooms in a single family residence. They may be up to 500 square feet in size and must include an efficient kitchen (sink, stove, refrigerator and counter). Some JADUs have their own bathroom, while others share with the main house. JADUs are a lower cost way to add a second unit, because the construction costs are much lower than a traditional second unit.
FAQs
How will my property taxes change when I complete the ADU or JADU? Will I lose my Proposition 13 values?
New construction to the existing home, including ADU, JADU and patios, pools etc. will be reassessed at market value upon completion. However, the existing land and structures not involved in new construction will not be reappraised. The increment of value determined for the new construction will be added to the existing assessed value. Example: Existing home assessed value: $236,500 Market value of ADU on completion: $100,000; Total new assessed value: $336,500
When will the new construction be assessed?
New construction is assessed at market value upon completion. If new construction is partially complete on the lien date (January 1) then a partial assessment will be added to the annual tax bill with the final value being assessed upon completion as a supplemental event.
How does the Assessor’s Office determine the assessed value for the newly constructed ADU/JADU?
The Assessor’s appraisal staff will use a variety of appraisal methods to determine the value of assessing the newly constructed ADU or JADU. On completion, the appraiser may look at cost, income, and sales comparison approach to determine the market value added for the new construction.
How will my assessed value change if I convert a portion of my home into an ADU without adding additional square footage? For example, I have a 2,500 sq. ft. home and will be converting 500 sq. ft. into a separate Accessory Dwelling Unit, keeping the remaining 2,000 sq. ft. as my main residence.
The increase in market value for the 500 sq. ft. conversion will be added to the current assessed value. For example, houses that are 2500 sq. ft. sell for $500,000 and houses that are 2000 sq. ft. with a 500 sq. ft. ADU sells for $625,000, so the increment of value at $125,000 would be the market value added for the conversion to an ADU. Example: Existing home assessed value: $500,000 Market value of ADU on completion: $125,000; Total new assessed value: $625,000