Glendora

Glendora permits ADUs in residential zones in line with California law while applying additional local standards for design, access and infrastructure. Both ADUs and Junior ADUs (JADUs) are allowed on qualifying properties and applications are reviewed ministerially if they meet all code requirements, meaning no public hearing is required.

The city also incorporates SB 9 regulations, allowing lot splits and additional units under specific conditions. To support the process, Glendora provides detailed handouts and requires certain affidavits to be submitted depending on the project type.

Glendora aligns with California’s broader ADU legislation but has its own requirements for height, setbacks and design review.

• Detached ADU: A standalone residential unit on the same lot
• Attached ADU: Connected to the primary residence
• Conversion ADU: Created within existing structures (garage, portion of home, etc.)
• Junior ADU (JADU): A unit within the primary residence, typically limited to 500 sq ft

• Maximum Size:
  
  • Detached: Minimum allowance of 800 sq ft (state mandate); up to 850 sq ft for 1-bedroom units and up to 1,000 sq ft for 2+ bedroom units
  • Attached: Up to 850 sq ft for 1-bedroom units and up to 1,000 sq ft for 2+ bedroom units, subject to primary dwelling size and site constraints
    

• Setbacks:
  
  • 4-foot minimum side and rear setbacks for new detached ADUs
  • Conversions within existing structures may not require additional setbacks
    
    
• Height Limits:
  
  • Detached ADUs typically allowed up to 16 feet 
  • Height may increase under state provisions depending on configuration and lot conditions
    
    
• Parking Requirements:
  
  • Parking is generally not required if:
    
    • The ADU is within proximity to transit
    • It is a conversion of existing space
    • It is located in certain designated areas

A complete ADU application in Glendora typically includes:

• ADU application forms (from official handouts) 
• Site plan and architectural drawings 
• Project details (type, size, construction scope) 
• Title and ownership documentation 
• Supporting affidavits (SB 9, JADU covenant, etc. where applicable)

Homeowners should also review Glendora current fee schedule, utility connection requirements, and fire code compliance.

In Glendora, ADU applications must be reviewed within 60 days once they are deemed complete, in accordance with state requirements. However, timelines can vary depending on project type and complexity, especially for SB 9 projects, which may take longer due to additional subdivision review processes. 

Overall, a standard ADU typically takes about 2-3 months from submission to approval, while SB 9 projects generally require more time depending on design complexity, site conditions and review requirements.

Most residential zones are eligible for ADUs in Glendora, including R-1 zones. Under state law, there is no minimum lot size requirement for standard ADUs in most areas. However, properties in hillside or environmentally sensitive zones may be subject to additional restrictions related to access, grading and environmental protection.

For the most current and complete information, refer directly to the City of Glendora.

Key documents include the ADU Handout (2026), SB 9 Urban Lot Split Requirements (2025), JADU Covenant Agreement Form and SB 9 affidavit and application materials, all of which provide detailed instructions for compliance and submission.