San Mateo County Zoning Code Ch. 8.110 Rh, Residential Hillside District

The purposes of the Residential Hillside District are to:

1. Provide residential areas intended primarily for the location of one-family dwellings, accessory structures and uses on hillside parcels;

2. Accommodate a compatible mix of institutional and recreational land uses to serve the needs of residential areas;

3. Protect the health, safety and welfare of residential inhabitants by restricting incompatible land uses;

4. Encourage architectural design and site planning which will preserve the natural character of hillside areas, particularly with respect to topography, vegetation and scenic qualities; and

5. Implement the policies of the San Mateo County General Plan, especially those concerning development in hillside areas.

(Prior Code § 6800 - 6815; Ord 2560 – 01/02/79)

(Prior Code § 6800 - 6810; Ord 3192; and 6811 – 6815 – Deleted by Ord 3192 – 10/24/89

(Prior Code § 6802(F)(3); Ord 4075 – 12/06/01)

(Prior Code § 6802.H(1); Ord 3791 – 10/21/97)

(Prior Code § 6802.(1); Ord 4844 – 05/04/21)

In the “RH” District all buildings shall be located at least 20 feet from the front and rear property lines. Buildings shall also be located so as to maintain a combined side yard setback of 20 feet with a minimum setback on any side of 7-1/2 feet.

Where an existing building has been built with a lesser setback than is required by the foregoing, the Design Review Committee, as part of the Design Review process, may permit a second story to be built with the same setbacks as the ground floor on the existing building where deemed appropriate.

However, if it is determined at any point, by a contractor or Building Inspection Section that the walls and/or foundation are in such substandard condition that they cannot support a second story without being totally replaced, then all such reconstruction shall meet current setback requirements and this exception would not be applicable.

One of the side yards shall provide a clear, safe, and effective means of access to the back of the parcel. The type of access provided shall be to the satisfaction of the Fire Marshal.

In the “RH” District, building height shall be limited in accordance with the following:

• (a) Building height at the highest point of the roof shall not exceed 28 feet. Building height shall be measured as the vertical distance from: (1) any point on the natural grade to the topmost point of the building immediately above, or (2) any point on the lowest floor, if the lowest floor is below the natural grade, to the topmost point of the building immediately above.

• (b) Plate height for any portion of a building that extends into the front setback shall not exceed 10 feet. Plate height shall be measured as the vertical distance from: (1) any point on the natural grade to the bottom of the lowest ceiling joist where the framing of the roof begins, or (2) any point on the lowest floor, if the lowest floor is below the natural grade, to the bottom of the lowest ceiling joist where the framing of the roof begins. No second story shall be allowed in any portion of a building that extends into the front setback.

• (c) Chimneys, pipes, mechanical equipment, antennae and other common facilities may extend beyond building height limit up to a maximum of 36 feet as required for safety or efficient operation.

Not more than twenty-five (25) percent of the building site shall be covered by: (1) buildings, (2) accessory buildings, or (3) structures such as patios, decks, balconies, porches, bridges and other similar uses which are eighteen (18) inches or more above the ground.

The frontage of all newly created parcels shall be a minimum of fifty (50) feet. In addition, the width of all newly created parcels shall be a minimum of fifty (50) feet at every point along the depth of the parcel. For the purposes of this section, depth shall mean a line drawn between the mid-points of the front and rear parcel lines. Width shall mean the distance between the side parcel lines as measured perpendicularly from the parcels’ depth.

The total floor area of all stories of all buildings, and accessory buildings on a building site shall not exceed thirty (30) percent of the total area of the building site or 2,400 sq. ft., whichever is greater.

Floor area specifically includes: (1) the floor area of all stories excluding uninhabitable attics as measured from the outside face of all exterior perimeter walls, (2) the area of all decks, porches, balconies or other areas covered by a waterproof roof which extends four (4) or more feet from exterior walls, and (3) the area of all garages and carports.

Floor Area Ratio will apply only to the following Use Modules: (1) One Family Dwellings, (2) Second Dwelling Units, (3) Residential Accessory Structures, (4) Residential Accessory Uses, (5) Small Hostelries, and (6) Residential Community Care Facilities. In addition, Floor Area Ratio will also apply to the following uses in the Neighborhood Institutional Facilities Module: (1) Institutional Day Care Facilities for Children, (2) Institutional Full-Time Care Facilities for Children, (3) Intermediate Care Facilities, and (4) Skilled Nursing Facilities.

A single and separate parcel of land which was a legal building site at the date of adoption of this ordinance shall continue to be a legal building site.

The amount of grading on a building site may not exceed 1,000 cubic yards. Whenever possible, grading should be kept to a minimum. Grading should be done in a manner that ensures stable soil conditions, minimizes erosion and controls storm runoff.

No more than fifty-five (55) building permits may be issued in any calendar year for the construction of any new residential structure in Emerald Lake Hills. The foregoing limitation shall not apply to replacement of a residential

structure, or any portion thereof, which is destroyed by natural disaster, fire, act of God or similar event, or to remodeling of an existing residential structure if the cost of the remodeling is less than fifty percent (50%) of the replacement value of the existing structure. The building permit limitation also shall not apply to a residential structure which is enforceably restricted for sale or rental to very low, lower, or moderate income households, as defined in the Housing Chapter of the San Mateo County General Plan.

(Prior Code § 6816; Ord 3194 – 10/31/89)