Before applying, make sure your property meets Monrovia’s basic ADU eligibility requirements:

• Your lot is zoned for residential use (e.g. RL, RE, RF, RM, or RH).
• Your lot is developed with at least one residential dwelling.
• Your property has space to allow for Monrovia’s setback requirements:
  • 4-feet from the side and rear property lines.
• If your property is in a historic district, additional rules may apply.
• If using a septic system, confirm with Public Works that your system can handle an ADU
• If the property is using a septic system, confirm with Public Works that your system can handle an ADU.
• Is the property and/or ADU is located within a Special Seismic Fault Zone, Hillside Area, or Special Geo Hazard or Landslide Zone? 
  • If yes, please contact the Building Division to determine if a geotechnical investigation report or an engineered grading plan is needed to evaluate all potential geological and seismic hazards.
•  Is the ADU located adjacent to slopes steeper than a 33.3% slope?
  • If yes, sufficient distance from slopes steeper than 33.3% is required to provide protection from slope drainage, erosion and shallow failures per Section 403.1.7 of the 2022 CRC. Alternative setbacks and clearances can be allowed if a geotechnical investigation is provided to demonstrate the above protection is satisfied.
• Would the project require the construction of a retaining wall to level the building pad area?
  • If yes, please contact the Planning and Building Divisions for additional requirements.
• Is the property located within the VHFHSV (Very High Fire Hazard Severity Zone)?
  • If yes, Fuel Modification Plans shall be required of properties located within the VHFHSZ. Note that the Monrovia Fire Department may require that the structure include fire suppression measures.  Please see the map online showing the location of the high fire hazard zone.

Contact the City of Monrovia Planning Division for assistance with your ADU application.

Email: planning@monroviaca.gov

Phone: (626) 932-5565

Select an available plan from Monrovia's Pre-Approved ADU Plan catalog. These designs have already been reviewed and vetted by the City of Monrovia to meet State ADU requirements and local development standards.

Once you select a pre-approved plan, reach out to the listed designer to begin the process. The designer will help customize the plan for your property, prepare a site-specific layout, and assist with application materials.

Your designer will update the cover sheet of the selected pre-approved plan with your property’s information, including your address, zoning, and relevant project details. This is required before plan submittal.

Complete the Plan Check Application and ADU Permit Application. Attach these forms, along with your customized ADU plans, and submit them by email to the Building Division: building@monroviaca.gov.

Quick tip: Your designer can help you prepare these application forms.

Once your application is accepted, City staff will review the plans for compliance. When using the pre-approved plans, permit review for ADUs will be shortened, thus allowing you to get to build your ADU sooner!

Once you have completed construction and have passed inspections you can enjoy your new ADU!

Contact Us:

Planning Division:

• 📧 planning@monroviaca.gov
• 📞 (626) 932-5565

Building Division:

• 📧 building@monroviaca.gov
• 📞 (626) 932-5581

Use of a Pre-Approved ADU Plan saves property owners time and money in the initial phase of constructing an ADU. Since the plans are pre-approved, it expedites staff review and approval of a building permit.

In the City’s initial selection of plans, the City chose five prototypes that met the State’s Streamlined Permit Standards and were under 800 square feet, as well as those that reflected the architectural character of the City. The five plans were selected as a part of the pilot program for pre-approved ADU plans and that the City will include more proposals over time. 

No, the City does not own the plans. To use a pre-approved ADU plan, homeowners must contact the architect who created it. The architect will help adapt the plan to your specific property.

The architect of the pre-approved plan sets the cost to use the plans. The City does not have the ability to limit such costs.

Contact the designer of the selected pre-approved plan to inquire about paying any fees. Although the City does not charge a fee to access the pre-approved plans, designers set their own fees for the time it takes to adjust the pre-approved plan to be site specific.

Yes, but any changes remove the pre-approved status and require full plan check.  The Pre-Approved ADU Plans can be modified but would require that the plans undergo additional plan check review to evaluate the changes. To retain the “pre-approved” status, plans may not be modified with deviations, alterations, or options beyond those expressly indicated in the plans.  The intent of providing the pre-approved plans is to reduce the cost and length of plan check review. The individual modification of the plans undoes the pre-approved nature of the plans.

No. These Pre-Approved ADU plans are only for new, detached structures.

No. These pre-approved ADU plans are only for new, detached structures.

Using the current selection of Pre-Approved ADU Plans, the City cannot require that the chosen Pre-Approved ADU match the architectural style of the primary dwelling in accordance with State law. The current selection of ADU prototypes all comply with the State’s Streamlined Permit Standards and are under 800 square feet. As a result, they cannot be subjected to the City’s Objective Design Standards. Future ADU prototypes that exceed 800 square feet will be subject to the objective design standards in MMC Section 17.44.005(E)(6).

The Pre-Approved ADU Plans may be used in conjunction with either single-family, multi-family or mixed-use development.

While the design and construction details of the pre-approved ADU plans have been pre-reviewed by Building and Planning Divisions, there are site-specific factors that need to be reviewed to ensure that your property is suitable for the selected ADU and that the siting of the ADU meets Building Code requirements. The pre-approved plans are only about 80% complete and will always require property-specific modification and documentation. For example, the ADU may not be suitable for your property if it is proposed to be located on a slope, under a high-voltage power line, or if it does not meet setback requirements. Depending on the existing conditions of the primary dwelling, there may also be additional requirements, such as installing fire sprinklers or solar panels. Lastly, other agency reviews and clearance requirements may apply depending on your site conditions.