Regulations

Building heights are regulated by the Zoning Ordinance (MMC 10.05). The maximum height for single-family and duplex homes is 30 feet, provided the roof has a slope of at least 3:12. Homes with flatter roofs are limited to a height of 25 feet. Heights for multi-family residential, commercial, and industrial buildings are 40 feet. Height is measured from the highest point of the roof to the closest exterior finished grade level directly below.

Setbacks are regulated by the Zoning Ordinance (10.05). The purpose of building setbacks is to create fire separation between structures, allow sunlight and ventilation, and provide privacy. All building setbacks are measured from property lines. Minimum ground floor setbacks for single-family homes are 20 feet in front, 5 feet on each side (10 feet on a street side), and 10 feet in back; upper floor setbacks are 10 feet greater in the front and on both sides, although there can be exceptions. Basic setbacks for commercial buildings vary from 0 to 20 feet in front, 0 to 10 feet on the sides, and 0 to 10 feet in back. Basic industrial setbacks are 25 feet in front, 10 feet on the sides, and 10 feet in back. Other requirements or possible exceptions to these provisions may apply.

Most projects benefit from some level of design review. Requests requiring Planning Commission approval will receive design review as part of that public hearing process, while all other requests will receive design review at staff level. Planning Division staff takes an active role in the review of site plans and architectural drawings for all types of projects. Discussions with the architect or other applicant for the project on matters of code compliance and aesthetic design are necessary to a high-quality final product and are most beneficial early in the review process. Project review criteria fall into two categories: objective and subjective. The objective criteria are all the applicable zoning regulations pertaining to building height and setback, lot coverage and floor area ratio, parking, and signage. The subjective criteria include impacts upon neighboring property owners' sunlight, privacy, and views, as well as the size, scale, and overall mass of the structure(s), use of exterior colors and materials appropriate for the architectural style, and whether the general appearance of the project is harmonious with its surroundings. Design review also includes the function and aesthetic compatibility of proposed signs, parking, landscaping, fencing, lighting, screening of utilities and the like, and amenities.

Not less than 60% of the front yard shall be landscaped (as defined in Article II of this chapter) with the exception that all site improvements required to provide disabled accessibility, to the extent not feasible in non-landscaped areas, may extend into the required landscaped area. The remainder of the front yard may be used for vehicular parking or storage (40%); however, all vehicular parking and storage areas shall be surfaced in compliance with this chapter. (Ord. 561, § 3.2, Amended by Ord. 603, § 2; Ord. 650, § 3; Ord. 726, § 2 (Att. A); 1976 Code § 10-1.402(1). Formerly 10.05.0140).

In addition, the Millbrae General Plan provides goals for front yard landscaping in residential areas "to preserve the quality of residential neighborhoods including with drought tolerant landscaping (Goal LU1) and; to "Ensure high quality landscape design for all new development, renovation or remodeling." (Goal LU2.1).

"Front yard" means a yard extending across the full width of the front of the lot between its front lot line and any portion of the front facade of the main building.

Usually the front property line follows the inner edge of the sidewalk, however this not always the case. The front property line is determined from the center-line of the street, therefor, sometimes there is city right-of-way located on the vegetated strip beyond the sidewalk or the owner property line may be set back from the sidewalk. Property owners are responsible for maintaining the natural vegetation strip adjacent to the public street. Please consult with Public Works to determine and verify the location of the front property line.

Only residents of the home may work at the home; other employees, if any, must work at an off-site location. A typical home-based business would be any type of handicraft made for sale at an off-site location, or a small office such as for a Realtor, contractor, or consultant. Limited inside storage of materials is permissible. Any business that would involve on-site automotive or other mechanical or electrical repairs, advertise the home address or have clients, customers, or frequent deliveries coming to the home is not allowed. The purpose of a Home Occupation Permit is to allow for minimal business use of the home while preserving the residential character of the neighborhood.

Any change to land or buildings usually requires prior City approval, either by staff or the Planning Commission. Applications may be submitted by anyone, but must be signed by the property owner.

Requests reviewed by staff include some sign applications (including temporary signs (PDF)), Home Occupation Permits, Business Licenses, ground floor additions to homes, temporary events, wireless communications facilities (which are governed by federal and local regulations), and Lot Line Adjustments. In most cases, these types of requests can be processed within 1 week. Staff decisions may be appealed to the Planning Commission.

The most significant changes must receive Planning Commission approval prior to obtaining a building permit. All non-ground floor changes to residential structures require Design Review approval and may also have a Use Permit, Variance, or Fence Exception associated with them. Significant changes to non-residential sites may require a Conditional Use Permit, Site Development Plan, or Master Sign Program (PDF) in addition to Design Review. All these requests require approval by the Planning Commission which meets twice a month. Applications must be submitted to the Planning Division for review of basic compliance with all applicable regulations before they can be scheduled for Commission consideration. Planning Commission review is a two-step process: 1) the first step is a Study Session in which all project issues are identified and usually resolved; 2) after one or more Study Sessions, the project will be scheduled for a Public Hearing at which time the Commission may legally take a final action on the request. All meetings are open to the public and public testimony is always welcomed.

Other requests requiring Planning Commission review include General Plan, Specific Plan, and Zoning Ordinance amendments, subdivisions, mixed-use, commercial, industrial, and multi-family residential projects, new duplex and single-family homes, some signs, and time extensions for already approved permits. The Planning Commission holds regularly scheduled meetings at 7 pm on the 1st and 3rd Mondays of every month in the City Council Chamber. A minimum 1 month lead time is necessary for staff review and public noticing of the request prior to the Planning Commission meeting. There is no application deadline; instead, a request will be scheduled when the application package is deemed complete by staff and a meeting agenda slot is available. Planning Commission decisions may be appealed to the City Council.

After being deemed complete, large or complex projects will be discussed at a Staff Review Board meeting prior to scheduling for Planning Commission. This is an opportunity for the applicant to informally discuss the technical aspects of a project with representatives from all City departments. These meetings are scheduled as needed and usually occur at 10 am on a Wednesday.

Certain requests, such as General Plan, Specific Plan, and Zoning Ordinance amendments, subdivisions, and development agreements, require final action by the City Council. Additional time is necessary for the preparation of staff reports for these matters following the Planning Commission's formal recommendation on them.

Lot coverage and floor area ratio (FAR) also limit development and are regulated by the Zoning Ordinance (MMC 10.05). Lot coverage limits the area of the "footprint" of all structures on a lot and is expressed as a percentage of total lot size. Cantilevered upper floors are part of a building's footprint. FAR limits the floor area of all levels of all structures and is expressed as a percentage of total lot size. The maximum lot coverage for single-family and duplex is 50%, 60 to 75% for multi-family, up to 100% for commercial, and 50% for industrial. The maximum FAR for single-family is 55%; there are no FAR maximums for other types of development.

Off-street parking is regulated by the Zoning Ordinance (MMC 10.05). The requirements for off-street parking are based on the type of land use and are expressed as ratios. For example, offices are required to provide 1 parking space for every 300 square feet total floor area, while the standard for restaurants is 1 space for every 2.5 seats. Parking requirements are enforced for new construction and when a more intensive use replaces a less intensive use (such as a restaurant replacing an office) on an already developed site. Required off-street parking cannot be met by including nearby on-street parking, but a parking-in-lieu fee may be approved by the Planning Commission.

Single-family homes are required to have a minimum of 2 garage (or equivalent) parking spaces. Driveways cannot count towards required parking, but a surface space off to one side may be considered. Newly constructed garages must provide minimum interior dimensions of 10 feet in width and 23 feet in depth per vehicle space. Large or expanded homes may be required to provide more than 2 parking spaces. Single-Family Parking Guidelines have been created to address a wide range of construction and site circumstances.

Detailed regulations for both temporary and permanent signs are contained in the Sign Ordinance (MMC 10.10). Signs are categorized by type (such as window, wall, projecting, hanging, and free-standing) and each has different limitations on size, height, number, and location. All permanent signs over 2 square feet in area and most temporary signs require a permit; however, signs not requiring a permit must still comply with certain requirements. All permanent signs needing a permit also require design review, either by staff or the Planning Commission; Commercial Sign Guidelines have been developed for this purpose. Approval of a sign permit for a new business is required prior to Planning Division approval of a Business License for that business.

The Subdivision Ordinance (MMC 10.15) regulates the creation of new parcels in the city. Under state law, any subdivision creating up to 4 lots requires approval of a Parcel Map and a subdivision containing 5 or more lots requires a Tract Map. The Planning Commission makes a recommendation on all subdivisions to the City Council which then makes the final decision. A condominium is also a subdivision and will require approval of a map. The creation of a new lot from an existing lot, often referred to as a "lot split", requires a Parcel Map. Changing the sizes of 2 adjoining lots by moving their common boundary is a Lot Line Adjustment. A Lot Line Adjustment is not a subdivision and therefore cannot change the number of lots, but must be mapped and is approvable by City staff. All zoning districts have minimum lot sizes and frontages with which all newly created or modified lots must comply. All approved maps must be recorded at the San Mateo County Recorder's Office in Redwood City.

Learn more about the Water Efficient Landscape Ordinance.