An ADU is an attached or detached residential dwelling unit which provides complete independent living facilities for one or more persons, including permanent provisions for living, sleeping, eating, cooking, and sanitation, which is located on the same lot as a single-family detached dwelling unit.

An ADU is intended to be secondary in size to the single-family residence. An ADU attached to a primary dwelling may be up to 50% of the size of the single-family residence, up to a maximum of 1,000 square feet. An ADU detached from the single-family residence may be up to 1,000 square feet, regardless of the size of the residence.

A JADU must be completely contained within an existing or proposed residence and cannot exceed 500 square feet.

STEP 1:   Obtain Permit Materials and Information

• Download Building Application and choose plan layout
• Building Application

 STEP 2:   Additional Submittal Requirements

• Site plan: Drawn to scale drawn by an Architect or Draftsman.
• Solar System for floor plans 3,4, and 5. Designed by a California licensed solar company of your choice. No deferred submittal allowed.
• Truss Structural Calculations: Designed by a truss manufacturer of your choice.

1. Spates Fabricators: 760-397-4122
2. Builders FirstSource: 760-770-3303
3. Omega Truss Systems: 760-986-7177

• Documentation specifying the roofing material to be used in compliance with the California Energy Commission cool roof material requirements.
• Sprinkler fire suppression system, if the existing home is equipped with a sprinkler fire suppression system the ADU will also be required to be equipped with a sprinklered fire suppression system. Plans will need to be prepared by a California licensed fire sprinkler contractor and submitted for approval to the Riverside County Fire Planning Department. The sprinkler system approval will need to be provided for permit issuance, no deferred submittal allowed.
  • How to submit to the Riverside County Fire Department: 
    • Please go to rivcoplus.org either log in or create an account
    • Apply for a permit
    • Scroll down until you reach Fire Commercial Permit
    • Upload the plans and application
    • Contact phone number: 760-863-8886

 STEP 4:   Application Submittal

• Submit your application materials to the Building Department via email at buildingservices@coachella.org.

 STEP 4:   Application Review

• Review will be conducted by the Building and Planning Departments. Turnaround time will be 3-10 business days for completed applications.

  STEP 5:  Permit Release/Construction/Inspection/Occupancy

• Once all reviews have been conducted and the necessary information has been provided, the Building Permit will then be issued. Construction can commence. Once all inspections have been completed, the new dwelling may be occupied.

Application:

Building Permit Application

Credit Card Authorization Form

Supplemental Information:

ADU Application Pkg (English)

ADU Application Pkg (Spanish)

JADU Application Pkg (English)

JADU Application Pkg (Spanish)

HCD Handout

ADU Guidelines

CONTACT

     E-mails: buildingservices@coachella.org or planning@coachella.org

ADU Plan Fees

JADU Plan Fees

Additional fee for panel upgrade of $310 (if applicable)

CONTACT

     E-mails: buildingservices@coachella.org or planning@coachella.org

Pre-Approved ADU's

Download Plan 1 Elevations & Floorplans:

• Mission Revival 
• Desert Modern 
• Spanish Colonial 
• Floorplan 1
• CAD Files

Download Plan 2 Elevations & Floorplans:

• Mission Revival 
• Desert Modern 
• Spanish Colonial 
• Floorplan 2
• CAD Files

Download Plan 3 Elevations & Floorplans:

• Mission Revival 
• Desert Modern 
• Spanish Colonial 
• Floorplan 3
• CAD Files

Download Plan 4 Elevations & Floorplans:

• Mission Revival 
• Desert Modern 
• Spanish Colonial 
• Floorplan 4
• CAD Files

Download Plan 5 Elevations & Floorplans:

• Mission Revival 
• Desert Modern 
• Spanish Colonial 
• Floorplan 5
• CAD Files

Download Plan 6 Elevations & Floorplans:

• Mission Revival 
• Desert Modern 
• Spanish Colonial 
• Floorplan 6
• CAD Files

Q:

For existing garage conversions to an ADU, does the existing wall within 5’ of the property
line need to be fire-rated?

A:

Yes, although the walls are existing they need to be modified to comply with the fire- rating 
and opening protection requirements of Table R302.1 (1) or R302.1 (2), whichever
is applicable.


Q:       

For existing garage conversions to an ADU, I intend to frame in the area where a garage
door used to be. Do I need to install a new footing even if the wall will still be non- bearing?

A:

Yes, all exterior walls must be supported by continuous footings per Section R403.1. The new 
footing shall comply with the current requirement in RCM 401.4 for expansive soil. However, if the 
existing footing and slab show no sign of damage or cracks, the expansive soil requirements may be waived.

Q:

For existing garage conversions to an ADU, do I need to comply with expansive soil conditions 
required in RCM 401.4?

A:

Since converting to an ADU would not be considered less conforming than the existing garage 
before the conversion, expansive soil conditions would not apply per Section 403.1 of the Existing 
Building Code. However, the concrete floor will need to be provided with a vapor retarder as 
required in Section R506.2.3. Alternate materials can be proposed to prevent the passage of water 
vapors. The following alternate products are approved for use on an existing slab that does not 
have a vapor retarder:

1. ICC ESR#1413 – RedGard Waterproofing and Crack Prevention Membrane, C-Cure Pro-Red Waterproofing Membrane 963, CBP 232 Waterproofing and Anti-Fracture Membrane, and Jambo Waterproofing Membrane
2.   ICC ESR #2417 – LATICRETE Hydro Ban
3.   ICC ESR #2785 – Polycoat-Aquatight and Flexideck
4.   ICC ESR#3474 – Mapelastic AquaDefense Waterproofing Membrane

Q:

For existing garage conversions to an ADU, do I need to upgrade or replace any structural 
members including foundation and slab?

A:

If gravity load carrying components have shown substantial structural damage, the damaged 
components must be replaced or rehabilitated per Section 404.3 of the Existing Building Code. If 
there is any sign of damage or deterioration in foundation or slab, it must be repaired or upgraded 
to the current code standards. A note requiring the owner to acknowledge possible upgrades needs to be placed on the plans.

Q:      

Do I need to obtain a separate address for an ADU?

A:

An ADU can be permitted under the existing address. However, if a separate address is desired, a 
request for a ½ fractional number to the existing main address needs to be requested.

Q:

Do I need to install a separate utility meter or a separate service panel for an ADU?

A:

No, however, the owner can request a separate utility meter or service panel if desired.

Q:     

Do I need to provide fire separation for an attached ADU?

A:

Yes, a 1-hour fire-resistance rating is required per Section R302.3. Additionally, these common 
walls and floor/ceiling assemblies between units must also meet a sound transmission rating of STC 50 or higher, per section 1207 of the building code.

Q:

What are the typical issues that are encountered when proposing existing garage conversions to 
an ADU?

A:

Ceiling joists may need to be upgraded due to additional loading of new ceiling drywall. Also, 
energy calculations will need to be submitted for creating a new conditioned space.

Q:

There is no building permit on record for my existing garage.  Can I still convert it to an  
ADU?

A:

If there is no record of building permit for the garage, you will need to apply for a new 
construction permit. The proposed ADU will need to comply with the current building code as if it 
were new. Foundation, gravity load resisting system, and lateral load resisting system will need to 
be verified and upgraded if not compliant with the current code. If the existing garage was 
previously permitted, the ADU conversion would be an alteration permit.

Q:

I would like to build a one-story addition to my existing garage to create an ADU. Do I need 
to reanalyze the entire structure?

A:

Yes, you will need to as you are increasing the lateral load to the existing garage per Section 
402.4.1 of the Existing Building Code. However, any existing lateral load-carrying structural 
element taking not more than 10% additional load (demand-capacity ratio) can remain unaltered.

Q:
I would like to build a detached ADU with a garage.  How big can my ADU be?

A:

The maximum living area of an ADU is 1,200 sf. Please contact Riverside County Fire Department 
if your proposed ADU is subject to the automatic sprinkler requirement.

Q:

Can a single heating unit be used to heat both the single-family dwelling and an attached ADU?

A:

No. Section R303.9 requires every dwelling unit be provided with heating facilities. Mechanical 
code section 311.4 and section 6.1 of ASHRAE 62.2 prohibits the transfer of air between adjacent 
dwelling units. Therefore, a separate heating unit is required for each dwelling unit, as a single 
heating system cannot separately balance air in both units without transferring the air between 
them. Furthermore section 120.2(a) of the energy standards includes that each dwelling unit shall 
be controlled by an individual thermostatic control.

Q:

Can the ADU sewer be connected to the existing house drainage/sewer system, or does it need a 
separate sewer connection to the main public sewer?

A:

Per section 311.1 of the plumbing code, an ADU *building sewer shall be separately connected to 
the public sewer, or trunk sewer. However, since the lot may not be subdivided in a manner that the ADU becomes a single family unit, the building sewer from the ADU may connect to the building sewer from the existing building at a point 2 feet outside of the existing building.

Exception: Where ADU stands in the rear of the existing building on an interior lot and no private 
sewer is available or can be built to the rear ADU through an adjoining court, yard, or driveway, 
the *building drain from the existing building may be extended to the rear ADU. This exception is 
also applicable to ADU’s that are physically attached to the existing building.

*Building Sewer. That part of the horizontal piping of a drainage system that extends from the end 
of the building drain and that receives the discharge of the building drain and conveys it to a 
public sewer, private sewer, private sewage disposal system, or other point of disposal.

*Building Drain. That part of the lowest piping of a drainage system that receives the discharge 
from soil, waste, and other drainage pipes inside the walls of the building and conveys it to the 
building sewer beginning 2 feet (610 mm) outside the building wall.

Accessory Dwelling Unit Electrical Requirements FAQs

*All sections reference the 2020 California Electrical Code unless otherwise noted.

Q:

I want to provide power to the ADU from the existing service panel at the main dwelling.  Is 
it necessary to upgrade my existing service or provide the ADU with its own service connection to 
the utility?

A:

A new service to the ADU or upgrade of the existing service will not be necessary if residential 
load calculations are performed to confirm the installation is sufficient. If the new calculated 
electrical loads exceed the rating of your existing service panel then an upgrade will be required. 
Electrical plan check is not required for installation of a panel rated at 400 amps or less, 
120/240V, single phase.

Q:

What do I have to do if I am upgrading the main service panel at the main dwelling to feed the 
ADU or installing a new service for the ADU?

A:

Residential load calculations shall be performed to verify the minimum rating of panel/service 
that will be required for the additional ADU electrical loads as per section 220.40.
New services require the installation of a grounding electrode system. The main service panel shall 
be connected to any and all available grounding electrodes present at the ADU or main dwelling per section 250.50.

Overhead service entrance conductors feeding the new panel shall be sized per section 310.15(B)(7) 
and be protected from physical damage per section 300.4.

Main service panels shall be rated appropriately for the environment where they will be installed. 
Outdoor panel boards need to be rated for wet or damp locations per section 408.37.
If there are more than six branch circuit breakers in the new service panel, a main overcurrent 
protection device is required per section 230.71.

Q:

Am I required to install a new meter for my ADU?

A:

No, a new meter is not required per code. The option is available to the homeowner to provide a new meter for the ADU.

Q:

My load calculations determined that the existing service will be sufficient for my ADU. What 
are the requirements if I want to provide power to the ADU via the existing main service panel or a 
subpanel that is located at the detached ADU?

A:

If installing a subpanel in a detached ADU, a grounding electrode system for the new subpanel 
will be required. If there are more than six circuits breakers installed in the new subpanel, a 
main circuit breaker is required per section 225.33(A). The minimum rating for the main circuit 
breaker shall be 60 amperes per section 230.79(D).

For an attached ADU, new circuits can be added to the existing service panel provided that the load 
calculations confirm it is acceptable to add the proposed circuits.

Q:

Are there any restrictions on where I can install indoor panels?

A:

Circuit breakers, and thus the panels housing those circuits breakers, cannot be located in 
clothes closets or bathrooms per sections 240.24(D) and (E).

Q:

Am I required to install AFCI protection for branch circuits that will serve my ADU?

A:

Per section 210.12(A), AFCI protection is required for all new branch circuits rated 120 volts, 
15- or 20-amperes installed in kitchens, family rooms, dining rooms, living rooms, parlors, 
libraries, dens, bedrooms, sunrooms, recreation rooms, closets, hallways, laundry areas, and 
similar areas. This includes kitchens, bedrooms, and living rooms, amongst the locations specified. 
Circuits in these areas that are modified, replaced, or extended shall have AFCI protection as well 
per section 210.12(B).

Q:

Am I required to install GFCI protection for receptacles that will serve my ADU?

A:

Per section 210.8(A), GFCI protection is required for all new receptacles rated 120 volts, 15- 
or 20-amperes installed in bathrooms, garages, outdoors, crawl spaces, unfinished basements, 
kitchens, within 6 ft. of a sink, bathtub, or shower stall’s outside edge, boathouses, and laundry 
areas.

Q:

Are there any additional receptacle requirements for my ADU?

A:

In the locations specified in section 210.52, all new 120 volts, 15- or 20-ampere rated 
receptacles shall be tamper-resistant receptacles per section 406.12(A).
One receptacle is required at both the front and back of the dwelling per section 210.52(E)(1). 
These receptacles shall have a weatherproof enclosure, be listed as weather-resistant, and be GFCI 
protected per sections 406.9(B) and 210.8(B)(4)

Q:

I am installing new lighting in my ADU, do I have to comply with California Energy Efficiency 
Standards?

A:

All new lighting installed in residential units is required to be rated as high efficacy as 
required by section 150.0(k), Table 150.0-A. At least one luminaire installed in bathrooms, laundry 
rooms, and utility rooms shall be controlled by a vacancy sensor per 150.0(k)(2)(J)

Q:

Are there any circuits that I am required to install in my new ADU?

A:

Yes, two small appliance circuits, one laundry circuit (if providing a laundry area), and one 
bathroom circuit are all required to be installed per sections 210.11(C)(1), (2), and (3). A 
lighting circuit in habitable rooms and bathrooms is required per section 210.70(A)(1). A
general receptacle outlet circuit shall be installed per section 210.52(A).