Introduction
Garage conversions are becoming more popular in Millbrae, providing residents with extra space for various uses. Whether you need a home office, a guest room, or a rental unit, converting your garage can meet these needs. It’s a smart way to make use of existing space without altering the main structure of your home. Plus, it can.
Essential Garage Conversion Rules for Millbrae
What you can build
Maximum Size
The maximum size for a garage conversion in Millbrae is 500 square feet, ensuring ample space for a small living area.
Side/rear setbacks
The required side and rear setbacks are typically 4 feet from the property line.
Height limit
The height limit for a garage conversion is 16 feet, which allows for a comfortable living space.
Building separation
There must be at least 10 feet of separation between the converted garage and the main dwelling.
Permitting Process Timeline
Standard
The standard permitting process takes about 60 days from submission to approval.
Historic Property review
For properties with historic designations, the review process can take up to 90 days.
Zoning Regulations in Millbrae
Zoning regulations help ensure that garage conversions fit within the community’s standards and aesthetics.
Garage Conversion Size Limitations
| Zoning District | Maximum Floor Area Allowed |
| R-1 (Single Family) | 400 sq ft |
| R-2 (Two Family) | 600 sq ft |
| R-3 (Multifamily) | 800 sq ft |
| R-4 (Neighborhood Mixed Use) | 1000 sq ft |
Height Limitations
Garage conversions in Millbrae must adhere to a height limit of 16 feet, ensuring the structures remain in scale with the surrounding buildings.
Building Coverage
The building coverage for a garage conversion should not exceed 40% of the total lot area, maintaining a balanced property layout.
Location
| Property Type | Location Requirement |
| Single-Family Homes | Must be attached or detached in the rear yard. |
| Duplex | Can be attached or detached, located in the rear yard. |
| Multifamily | Allowed in designated areas only. |
Exterior details
The exterior design of the garage conversion must match the main dwelling to maintain visual harmony.
Setbacks and Buffer Zones
Garage conversions must respect a 4-foot side and rear setback to ensure privacy and accessibility.
Minimum Lot Area
Connection for utilities
All garage conversions must connect to the main utilities, including water, sewer, and electricity.
Fire safety
Garage conversions must include fire safety features such as smoke detectors and fire-resistant materials.
Room specifications
- Living Area: The living area should be at least 150 square feet to provide a comfortable space.
- Kitchen: A functional kitchen with at least 50 square feet is required.
- Bathroom: A bathroom with a minimum of 30 square feet must be included.
- Ceiling Height: The ceiling height must be at least 7 feet to meet building codes.
Short-term Rentals and Home Occupations Regulations
Short-term rentals and home occupations in garage conversions must comply with local regulations.
Building Codes
Garage conversions must adhere to all local building codes to ensure safety and compliance.
Millbrae Garage Conversion Permit Guidelines
| Permit Type | Description | Estimated Fee |
| Building Permit | Required for structural changes | $500 |
| Electrical Permit | Necessary for electrical work | $150 |
| Plumbing Permit | Needed for plumbing installations | $200 |
| Mechanical Permit | For HVAC and other mechanical systems | $100 |
| Planning Review | Ensures compliance with zoning regulations | $300 |
Property Requirements
Garage conversions must meet all property requirements, including lot size and zoning rules.
Parking
Parking regulations require that at least one off-street parking space is maintained.
Front Setbacks
Front setbacks must be at least 20 feet to keep the structure aligned with the neighborhood.
Side and Rear Setbacks
Side and rear setbacks must be at least 4 feet to provide adequate space around the structure.
Open Space and Rear Yards
A portion of the lot must remain as open space or yard to ensure outdoor living areas are preserved.
Properties That Qualify
Properties must be in compliance with local zoning laws to qualify for garage conversions.
Development standards
Single-family Homes
Must adhere to all zoning and building regulations.
Multi-family Properties
Additional units must meet specific requirements.
Duplex Properties
Must comply with zoning laws and provide adequate parking.
Property designations
- Flood Zones: Garage conversions in flood zones must meet additional safety standards.
- Easements: Easements must be respected, and no building is allowed within these areas.
- Historic Properties: Additional review and guidelines apply to historic properties to preserve their character.
Summary
Garage conversions in Millbrae offer a fantastic way to create additional living space while increasing property value. Adhering to local regulations ensures a smooth process and a successful project.
FAQs
The standard permitting process typically takes about 60 days from submission to approval. For historic properties, it can take up to 90 days. This timeline helps ensure that all necessary inspections and reviews are conducted thoroughly.
The maximum size allowed varies by zoning district, but generally, it ranges from 400 to 1000 square feet. This ensures the conversion fits within the community standards. Always check local regulations for specific limits.
Yes, you will need various permits, including building, electrical, plumbing, and mechanical permits, as well as a planning review. These permits ensure that your conversion meets all safety and zoning requirements. Obtaining these permits is crucial for legal compliance.
Yes, but you must comply with local regulations for short-term rentals, which may include additional permits and inspections. These regulations help maintain community standards. Failure to comply can result in fines or penalties.
Yes, the height limit for garage conversions in Millbrae is 16 feet. This height limit ensures that the conversion does not overshadow neighboring properties. Always check the specific zoning codes for your area.
Yes, the exterior design of the garage conversion must match the main dwelling to maintain visual harmony. This requirement helps preserve the aesthetic of the neighborhood. Consistent design enhances the overall appeal of your property.
Yes, a minimum lot area of 5,000 square feet is required. This requirement ensures adequate space for the conversion and surrounding areas. Adequate lot size is crucial for meeting zoning regulations.
Side and rear setbacks of at least 4 feet are required. These setbacks ensure privacy and adequate spacing between properties. Compliance with setbacks is essential for obtaining permits.
Yes, a bathroom with a minimum of 30 square feet must be included in the conversion. This inclusion ensures the livability of the space. Bathrooms must meet local plumbing codes.
The ceiling height must be at least 7 feet to meet building codes. This height ensures a comfortable living space. Lower ceilings may not meet legal standards.
Yes, all garage conversions must connect to the main utilities, including water, sewer, and electricity. This connection ensures that the converted space is functional. Proper utility connections are essential for health and safety.
Yes, garage conversions must include fire safety features such as smoke detectors and fire-resistant materials. These features help protect occupants in case of fire. Fire safety compliance is mandatory for all conversions.
Yes, but additional safety standards must be met for properties in flood zones. These standards help protect the structure from flood damage. Compliance with flood zone regulations is crucial for safety.
At least one off-street parking space must be maintained. This requirement helps manage parking congestion in the neighborhood. Lack of adequate parking can lead to fines.
Yes, a portion of the lot must remain as open space or yard to ensure outdoor living areas are preserved. This requirement helps maintain the neighborhood’s aesthetic and functionality. Open spaces are vital for community well-being.
Yes, a planning review is required to ensure compliance with zoning regulations. This review ensures that your conversion meets all local standards. Planning reviews are an essential part of the approval process.
Easements must be respected, and no building is allowed within these areas. Easements are designated for specific uses and cannot be obstructed. Ignoring easements can lead to legal issues.
Additional review and guidelines apply to historic properties to preserve their character. Historic properties must meet specific standards to maintain their designation. These guidelines protect the historical integrity of the property.
Yes, additional units must meet specific requirements for multi-family properties. These requirements ensure that each unit is safe and functional. Multi-family properties often have stricter regulations.
Yes, but you must comply with zoning laws and provide adequate parking. Duplex properties have specific regulations that must be followed. Compliance ensures that the conversion is legal and functional.
The number of rooms is generally limited by the size and layout of the garage, as well as zoning regulations. This limitation ensures that the space remains livable and compliant. Overcrowding can lead to safety issues and legal non-compliance.
