The construction of An ADU in San Bernardino, California

The construction of An ADU in San Bernardino, California

According to state law, each single-family San Bernardino ADU must have at least one accessory dwelling unit. One junior accessorized dwelling unit could be added to each owner-occupied single-family home. Multi-family properties, every four residential units could add one Accessory Dwelling Unit so that the units are legally in place.

Attached ADU

Attached ADUs are ADU that is connected to your home. Also known in the field of Addition ADUs, or “bump-out ADUs. These ADUs are accessible through the main house via an entrance at their connection points. However, they could be distinct from the primary home.

Detached ADU

The separate ADU is not linked to the main home. The building must be within the property setbacks and allowed building size (both in square footage and height) ).

Junior ADU

Judicial Accessory Dwelling Units (JADUs) are so named because they are tiny (up to about 500 square feet).

 In California, the latest state legislation, AB68 and AB 881 allow the construction of both an ADU and a junior ADU (JADU) on the same property with the possibility of a single-family residence. That means you could have two buildings on your property: ADU and JADU.

Property Requirements

Multi-family and single-family San Bernardino ADU   are permitted to build as much as 850 square feet in one-bedroom ADU and up to 1000 square feet in a two-bedroom ADU, irrespective of the Zoning Standards on which the building is located. A Junior ADU with a maximum of 500 square feet can be built. The minimum size of living space is 150 square feet per the California Residential Code.


Owner-occupancy is not required in the case of newly constructed Accessory Dwelling Units (ADU) (both conversions and new construction) between 2020 and 2025. This is the SB13 update.

Number Of Adus Allowed

By state law, every single-family residence can now be added to a minimum of one accessory dwelling unit. Two types of accessory dwelling units can be added to a single-family home that its owner owns. Multi-family homes could add one Accessory Dwelling Unit for every four residential units, as they were legally created.

Adu Size

Suppose a San Bernardino ADU is built on a single or multi-family residential property. In that case, it won’t have to meet the requirements for the minimum size of many of the Zoning Codes or any special ordinances. ~ AB-68


The replacement parking requirement does not apply to areas that convert an existing garage into an Accessory Dwelling Unit (ADU) or Junior ADU as per AB68.


Height restrictions are not specified in state standards.

Fire Safety

Accessory dwelling units will not have to have fire sprinklers if they are not part of the primary home and may use other ways to prevent fire. (State requirements)

Utility Connections

It is necessary to obtain approval from the local health officer before installing a sewage disposal system for private use. (Requirements of the state)


There are no design restrictions specified in state standards.


The maximum setback required on a detached, new-construction accessory dwelling unit should not exceed 4 feet from the side and rear property lines. Setbacks are unnecessary for Accessory Dwelling Units (ADU)s and Junior ADUs converted from legally established spaces. Connected Accessory Dwelling Units (ADU)s and conversions of existing areas to expand will need to be confirmed with setbacks for the underlying zone.

Review of the design

State Standards don’t require any further design reviews.

Next Steps

To begin working on your ADU, Here are the first steps.

Contact Your City

Search Google to find your city’s contact phone number. For example, “City of Phoenix Residence Permits Contact No.”

You can contact the main line to be directed to the department for permits.