Building an ADU in Fremont, California

Learn permits, rules, and guides to building in Alameda County
No items found.

Overview

Fremont is located in Alameda County in California. Fremont has a total population of 214089 over a land mass of 77.46 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

According to state law, all single-family homes are allowed at least one ADU. Additionally, single-family parcels which are owner-occupied may create one ADU and one JADU. Also, multi-family parcels may now add one ADU per every four existing residential units, so long as they were legally established.

Property Requirements

Single-family and multi-family Parcels will be allowed to create up to 850 square ft. for a one bed ADU or up to 1,000 square ft. for a two bed ADU, regardless of the underlying zoning standards of the property. A JADU up to 500 square ft. is allowed. The minimum size of any living unit (including ADUs and JADUs) is 150 square ft. according to Califronia Residential Code. ~ AB68 & AB881 Update

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
Between between 2020 and 2025, owner occupancy requirements will not apply to new Accessory Dwelling Unit (ADU)s. (applicable to new construction and conversion units) ~ SB-13
Number of ADUs Allowed
According to state law, all single-family homes are allowed at least one ADU. Additionally, single-family parcels which are owner-occupied may create one ADU and one JADU. Also, multi-family parcels may now add one ADU per every four existing residential units, so long as they were legally established.
ADU Size
Accessory Dwelling Unit projects on single family or multi-family residential parcels will not be subject to the minimum lot size of the underlying local zoning code or by special ordinance. ~ AB-68
Parking
Properties which convert an existing garage to an Accessory Dwelling Unit (ADU) or JADU will not be subject to replacement parking requirements. ~ According To AB68
Height
ADUs may not exceed the building height limits applicable to the principal residence.
Fire Safety
If a detached structure, the ADU must be separated from other habitable structures on the lot by at least 10 feet. This may be reduced to eight feet if one structure is equipped with fire sprinklers or six feet if both structures are equipped with fire sprinklers. Other exceptions may apply.
Utility Connections
Permits from the Alameda County Water District (ACWD) and Union Sanitary District (USD) may also be required. A fee is required for the building permit and may be required for other permits.
Aesthetic
ADUs shall incorporate architectural features, building materials and colors that are compatible with the principal residence. 1. Outside stairways to the ADU shall not be in the front of the principal residence. 2. A continuous paved pathway from the street to the front door of the ADU (called a “passageway”) may be added, but is not required.
Set backs
The maximum required setback for a detached new construction ADU shall be no more than 4 ft. from the rear and side property lines. Setbacks will not be required for ADUs and JADUs converted from existing space that was legally eastablished. Attached ADUs and conversions from existing space to be expanded will be required to comply with the setbacks of the underlying zone. ~ AB68 & AB881 Update

Design Review

An application for an ADU that meets the applicable standards in the Fremont Municipal Code (FMC) is subject only to ministerial review and approval. This means that the application may be approved by staff and no public hearing is required. Where design review requirements are applicable (for example, for an addition or a new detached structure), a Ministerial design review Permit is required.

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

See what can go on your property. A site Analysis is the first step for any construction

Start with a Site Analysis