Building an ADU in San Bernardino, California

Learn permits, rules, and guides to building in San Bernardino County
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Overview

San Bernardino is located in San Bernardino County in California. San Bernardino has a total population of 209924 over a land mass of 59.20 Square Miles. When it comes to ADUs, the city allows for 1+ ADUs on a given property, and a square footage of 850-1,000 sf

Number of ADUs Allowed

1+

Size of ADU Allowed

850-1,000 sf

Types of ADUs Allowed

Detached, Junior, Attached

Permit Cost

Coming Soon

Number of ADUs allowed

Under state law, each single-family home may now add at least one Accessory Dwelling Unit. Owner occupied single-family properties may add one Accessory Dwelling Unit and one Junior Accessory Dwelling Unit. Multi-family properties, per every four existing residential units, may add one Accessory Dwelling Unit, so long as the existing units were legally established.

Property Requirements

Single-family and multi-family Parcels will be allowed to create up to 850 square feet for a one bedroom ADU or up to 1,000 square feet for a two bedroom ADU, regardless of the underlying zoning standards of the property. A Junior ADU up to 500 square feet is allowed. The minimum size of any living unit (including ADUs and Junior ADUs) is 150 square feet according to Califronia Residential Code. ~ According To AB68

Types of ADUs Allowed

Attached ADU

An attached ADU is one that is attached to your house. Also know as Addition ADUs or “bump-out ADUs. These types of ADUs can be accessed from the primary house with a door in the connection point, but also can be independent of the main home.

Dettached ADU

A detached ADU is not connected to your primary house. The dwelling needs to be within your property setbacks and allowable building size (both height and square footage).

Junior ADU

Junior Accessory Dwelling Units (JADUs) are named this way because they are small (up to 500 square feet).

In California, the recent state bills AB68 and AB 881 permits both an ADU and a Junior ADU (JADU) on the same lot with a proposed or existing single-family dwelling. This means you can have two units on your lot: ADU, and JADU.

Property Requirements

Ownership
Owner-occupancy will not be required for new Accessory Dwelling Unit (ADU)s (conversion and new construction) built between 2020 and 2025. ~ SB13 Update
Number of ADUs Allowed
Under state law, each single-family home may now add at least one Accessory Dwelling Unit. Owner occupied single-family properties may add one Accessory Dwelling Unit and one Junior Accessory Dwelling Unit. Multi-family properties, per every four existing residential units, may add one Accessory Dwelling Unit, so long as the existing units were legally established.
ADU Size
Accessory Dwelling Unit projects on single family or multi-family residential properties will not be subject to the minimum lot size of the underlying local zoning code or by special ordinance. ~ AB-68
Parking
Replacement parking shall not apply to lots which convert an existing garage to an Accessory Dwelling Unit (ADU) or Junior ADU. ~ According To AB68
Height
State Standards don't specify height restrictions.
Fire Safety
Accessory dwelling units shall not be required to provide fire sprinklers if they are not required for the primary residence and may employ alternative methods for fire protection. (State requirements)
Utility Connections
Local health officer approval where a private sewage disposal system is being used, if required. (State requirements)
Aesthetic
State Standards don't specify design restrictions.
Set backs
The maximum required setback for a detached new construction Accessory Dwelling Unit (ADU) shall be no more than 4 ft from the rear and side property lines. Setbacks will not be required for Accessory Dwelling Unit (ADU)s and Junior ADUs converted from existing space that was legally eastablished. Attached Accessory Dwelling Unit (ADU)s and conversions from existing space to be expanded will be required to comply with the setbacks of the underlying zone. ~ AB-68

Design Review

State Standards don't require any additional design review.

Next Steps

To get started on your ADU, here are some first steps.

Call Your City

Search Google for your city’s contact number. An example would “City of Phoenix Residential Permits Contact Number”

You can call the main line and get directed to the permitting department.

Ask these questions...

1) Can I put a secondary home on my lot (Accessory Dwelling Unit)?
2) What are my livable setbacks, and ADU size regulations?
3) Can I put a prefabricated guest house on my property?

Get Started With a Modular Home

Find a Modular Home

Use our prefab discovery tool to help you find the perfect home.

Get a Site Analysis

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