ADU – Accessory Dwelling Units

Have you ever felt the need for more space in your home because you have multiple family members living with you or extended family members wanting to stay with you? Or you own a single family home as an investment and want to maximize the cash flow from the home.  An ADU (Accessory Dwelling Unit) is a great option to provide those benefits.

What is an ADU?

An Accessory Dwelling Units (ADU’s) is a secondary small dwelling located on the same property as a single family home. They are common known as in-law units or granny flats.

They could be

  • Attached
  • Detached from the main home.
  • Above a garage.
  • Converted garage.
  • In a basement or attic.

Because of the housing shortage and high rents throughout the state of California the state made changes to the law allowing more homeowners the opportunity to build an ADU. This can help to address the need for more affordable housing.

What are the benefits of an ADU to you?

  • A lot more affordable to build.
  • The flexibility to have extra living space for family members or out of town guests.
  • Allow senior parents to age in place, while they are near and maintain privacy.
  • It can be an additional source of income.
  • It can help to increase your property value.
  • Maximize your investment property and increase your cash flow.
  • Downsize – Live in the ADU unit while renting out the primary home.
  • Could be a great investment since the build costs to rental ratio is better.
  • Can help to ease the housing challenges in the area.

If you are located in the city of San Jose here is a quick guide for you.

San Jose ADU guidelines: http://www.sanjoseca.gov/ADUs
Item             Prior Regulation             Regulation
Effective July 27, 2018
Zoning District ADUs allowed in R-1, R-2, and PD (subject to R-1 standards) zoning districts, which are comprised of single-family residences. Additionally allow ADUs in R-M zoning districts, and in any Planned Development (PD) district where ADUs are not expressly prohibited. Development standards of the Municipal Code and of planned developments zones apply in call cases.
Minimum Lot Size 5,445 sf 3,000 sf
Minimum Setbacks from Rear and Side Property Lines 0 feet – Conversions 5 feet – New construction 0 feet – 1-story conversions 5 feet – New construction or for ADUs constructed above a garage or accessory structure.
Maximum Height Single story – 18 feet maximum No 2nd-story unit allowed Single story – 18 feet maximum
2nd-story allowed – 22 feet maximum*  *Either an ADU atop a garage or accessory structure or a two-story ADU.
Rear Yard Coverage Not including pools, not more than 40% of the rear yard may be covered. No change
Detached ADU Location Rear yard only, at least 6 feet away from primary dwelling, attached only to a detached garage. Rear yard only, at least 6 feet away from primary dwelling, attached to a detached garage or other existing accessory structure.
ADU Size
(in sf)

Lot Size (sf)

ADU Maximum Size (sf)

3,000 – 5,444

Not allowed

5,445 – 9,000

600

9,001 – 10,000

650

10,001 – Up

800

Lot Size (sf)

ADU Maximum Size (sf)

3,000 – 5,444

600

5,445 – 9,000

700

9,001 – 10,000

800

10,001 – Up

900

Number of Bedrooms Studio or 1 bedroom Under 800 sf: Studio or 1 bedroom allowed 800 sf and up: 2 bedrooms maximum allowed
Attached ADUMaximum Floor Area May not exceed 50% of the existing primary dwelling living area May not exceed 50% of the existing or proposed primary dwelling living area
Design Standards Match appearance, and match roof form and pitch Require visual compatibility with existing primary dwelling.
Parking requirements Parking configurations in conformance with State law

An ADU requires 1 space unless the property qualifies for an exemption under State law—see the Parking section of this webpage. If a garage has been converted, the main dwelling parking space must be replaced, as uncovered or in front or side setback areas. Parking spaces may be configured on-site per state law.

Reduction in required off-street parking spaces No more than one dwelling occupies the lot. (Section 20.90.220) No more than one dwelling, in conjunction with an ADU, occupies the lot.
Junior ADU Not allowed Removed from consideration; not part of the approved ordinance.
Front yard paving No more than 50% of the front setback may be paved with any impervious surface. (Section 20.30.440) No more than 50% of the front setback may be paved with any impervious or pervious surface.
ADU requirements for lots in Historic Resources Inventory Requires Single-Family House Permit Waive requirement for a Single-Family House Permit for detached ADU or for conversion of existing accessory structure with no exterior alterations.

 

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Aloha Agent | Marlo Ibon

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