San Anselmo Municipal Code § 10-3.412 Maximum Floor Area and Maximum Lot Coverage for Dwellings and Improvements…

This article establishes the development standards deemed the minimum necessary to promote and protect the public health, safety, and general welfare of the Town.

(§ 1, Ord. 917, eff. February 26, 1991)

(Ord. No. 1069, 3-24-2009)

The Development Standards Table, referred to as Table 4A, lists the development standards for each Zoning District. Deviations from development standards set forth in the Development Standards Table, referred to as Table 4A, may only be permitted by (1) an exception; (2) a minor exception; or (3) a design review, each of which are listed on the Minor Intrusions into Required Development Standards For Residential Properties Table, referred to as Table 4B; or (4) a variance by the Planning Commission as set forth in Section 10.3.1404(b) of this chapter of the San Anselmo Municipal Code; or (5) pursuant to specific exceptions for certain two-unit developments and subdivisions set forth in Chapter 4, Housing Developments Under Government Code Section 65852.21, and Chapter 6, Accessory Dwelling Units.

The Residential Housing Opportunities (R-HO), Public Facilities (PF), and Open Space (OS) Districts are not included on Table 4A. The R-HO District is an overlay district and utilizes development standards for the underlying District. The PF and OS Districts do not include any development standards but allow for the use of development standards appropriate to the specific use or project site as determined by the Planning Commission or the Town Council.

(§ 1, Ord. 917, eff. February 26, 1991, as amended by Exh. A, Ord. 1012, eff. April 13, 2000, and § 3, Ord. 1044 (part), eff. July 28, 2005)

(Ord. No. 1069, 3-24-2009; Ord. No. 1115, § 4, 2-28-2017; Ord. No. 1128, § 1, 11-13-2018; Ord. No. 1138, § , 9-24-2019; Ord. No. 1159, § 7, 12-14-2021; Ord. No. 1160, § 7, 12-14-2021; Ord. No. 2025-1190, § 2(Exh. A)(6), 5-27-2025)

DEVELOPMENT STANDARDS TABLE TABLE 4A

(Ord. No. 1069, 3-24-2009; Ord. No. 1128, § 2, 11-13-2018; Ord. No. 1179, § 4(Exh. A), 8-22-2023; Ord. No. 1184, § 3, 1-9-2024; Ord. No. 2025-1190, § 2(Exh. A)(6), 5-27-2025)

All setback measurements shall be made as follows:

(a) The setback measurement shall be taken from the nearest point of any building, architectural feature, or improvement to the nearest point of any property line; or

(b) If a future right-of-way line or a future width line has been established for a street by provisions of any applicable ordinance, the measurement shall be taken from the nearest point of any building, architectural feature, or improvement to the nearest point of the future right-of-way line or nearest point of the future width line.

(§ 1, Ord. 917, eff. February 26, 1991)

All height measurements shall be made as follows:

The height of a building, structure, or improvement shall be that vertical distance measured from the average level of the highest and lowest point of that portion of the lot ground surface covered by the building, structure, or improvement, to the highest point on the roof, ridge, or parapet wall. Height limitations shall not apply to public utility transmission and distribution lines.

(a) A chimney up to twelve (12) square feet may exceed the maximum building height by four (4) feet.

(b) For R-1 H, R-1 C and R-1 properties no development, including structures, roads, and public facilities shall be allowed on visible ridges and hillsides unless it has been demonstrated to the satisfaction of the Town Engineer and Planning Commission that development outside of the ridge zone is not feasible for geologic, soils, or hydrologic reasons, or development would impact a unique natural habitat, and if development is allowed on visible ridges and hillsides, the maximum height shall be no more than eighteen (18) feet above the ridgeline.

(c) The ground surface for determining building height shall be either the predevelopment ground elevations at the appropriate points or the finished grade elevations at the appropriate points. The finished grade elevations may be used only if they are approved by specific action of the Planning Commission.

In approving the finished grade elevation as the governing ground surface, the Planning Commission shall make all of the following findings:

(a) That use of the finished grade elevation in lieu of the predevelopment ground surface will produce results consistent with the intention to minimize visual impact on the ridge zone;

(b) That use of the finished grade will benefit the public welfare and other properties in the area;

(c) That use of the finished grade will not result in any substantial obstruction of visible ridgeline or view from other properties in the Town.

These requirements assume evenly graded surfaces. When local irregularities in the ground surface produce results which are in conflict with the intent of these requirements, the Planning Commission shall determine reasonable, average ground surface conditions in the vicinity of the governing points and instruct the Public Works Director to make structure height calculations based on these reasonable average conditions.

The intention of the height limits is to produce structures which minimize visual impact on the ridge zone. If, during the design review process associated with a particular structure, a design emerges which is in compliance with these limits, but in conflict with the intent of the ordinance codified in this article, the Planning Commission shall have the authority to amend these limits in order to achieve the original intention of these limits.

Prior to any amendment of these height limits, the Planning Commission shall make all of the following findings:

(a) That such amendment will better achieve the purpose of the ordinance codified in this article.

(b) The amendment in height limits will benefit the public welfare and other properties in the area.

(c) The amendment will not result in the substantial obstruction of a visible ridgeline or the obstruction of views from other properties in the Town.

Building site locations shall be selected to reduce visibility providing such locations can be served with reasonable access and are geologically stable. The preliminary and precise development plans shall be based on a grading plan designed to retain the natural features of the land. Cuts and fills shall be kept to a minimum, and rounded and contoured to blend with existing topography.

(§ 1, Ord. 917, eff. February 26, 1991)

(Ord. No. 1069, 3-24-2009)

The Minor Exceptions to Required Development Standards for Residential Properties Table, referred to as Table 4B, lists: (a) exceptions, which require no discretionary action by the Community Development Director or designee, or Planning Commission; (b) minor exceptions, which require discretionary action by the Community Development Director or designee; and (c) minor intrusions that require Planning Commission design review.

(§ 1, Ord. 917, eff. February 26, 1991, as amended by § 3, Ord. 1044 (part), eff. July 28, 2005)

(Ord. No. 1115, § 5, 2-28-2017; Ord. No. 2025-1190, § 2(Exh. A)(7), 5-27-2025)

MINOR EXCEPTIONS TO REQUIRED RESIDENTIAL DEVELOPMENT STANDARDS Table 4B(1)(2)(3)

(Ord. No. 1069, 3-24-2009)

(Ord. No. 1108, § 2, 7-26-2016; Ord. No. 1115, § 7, 2-28-2017; Ord. No. 1176, § 5, 4-25-2023; Ord. No. 2025-1190, § 2(Exh. A)(7), 5-27-2025)

The purpose and intent of allowing exceptions to the development standards is to permit minor intrusions into required setback areas. If, in the judgment of the Planning Director, the structure is not a minor intrusion due to its size, location, or potential use, the Planning Director shall require that the structure either adhere to the standards listed in the Development Standards Table, referred to as Table 4A, or obtain a variance from the Planning Commission, as set forth in Section 10-3.1404(b) of the San Anselmo Municipal Code.

(§ 1, Ord. 917, eff. February 26, 1991)

(Ord. No. 1115, § 6, 2-28-2017)

(a) There may be only one building site on any lot. Each lot may be permitted to have constructed accessory buildings as may be regulated by provisions of the San Anselmo Municipal Code. Lots having sufficient area for more than one building site may be divided in conformance with the Subdivision Ordinance, the Development Standards Table, referred to as Table 4A, and subject to the following:

(1) Whenever a division would create a lot without full street frontage, the lot shall have an area no less than the minimum lot area required within the District as set forth in the Development Standards Table, referred to as Table 4A; and

(2) Each lot not having full street frontage shall have a permanent access way not less than twenty (20′) feet in width at any point extending to a street; and

(3) The area of the lot shall not include that area devoted to a permanent access way.

(b) Each lot shall have direct access to a public street and shall not obtain access by easement or fee title across an adjacent lot except by the approval of a variance in accordance with Section 10-3.1404(b) of the San Anselmo Municipal Code.

(c) Except as provided in California Government Code Section 66411.7, no lot shall be divided into two (2) or more parcels in any manner, so as to produce a remaining lot having an area less than the minimum lot area required within the District as set forth in the Development Standards Table, referred to as Table 4A.

(§ 1, Ord. 917, eff. February 26, 1991, as amended by § 2 (Exh. A), Ord. 984, eff. July 10, 1997)

(Ord. No. 1159, § 8, 12-14-2021; Ord. No. 1160, § 8, 12-14-2021)

Except as provided in California Government Code Section 66411.7, each primary building and all accessory buildings erected shall be located on a building site or lot in one (1) ownership having an area and width no less than the minimum required for the respective District, excepting:

That any lot or building site having less than the required minimum area and/or width may be used for the construction or erection of a primary building and accessory buildings as may be permitted or conditionally permitted by the District, if:

(a) All other requirements of this chapter are complied with; and

(b) The lot was under one (1) ownership at the time of adoption of Ordinance No. 190; and either

(i) The lot was legally subdivided after the adoption of the Town's first Zoning Ordinance (Ordinance No. 190, effective June 7, 1926), but prior to the adoption of an applicable subdivision ordinance in accordance with the area, width, and frontage requirements of the zoning ordinance in effect at the time of the subdivision; or

(ii) The lot was subdivided pursuant to the Town's first Subdivision Ordinance (Ordinance No. 248, effective September 9, 1937) or pursuant to a subsequent subdivision ordinance.

(§ 1, Ord. 917, eff. February 26, 1991; Ord. No. 1150 § 2(Exh. 1), 9-22-2020)

(Ord. No. 1159, § 9, 12-14-2021; Ord. No. 1160, § 9, 12-14-2021)

The Slope Density/Lot Area Table, referred to as Table 4C, lists the minimum lot size for the R-1 District for lots which have average slopes of fifteen (15%) percent or greater. All calculation of minimum lot areas for lots subject to Table 4A shall not benefit from arithmetic rounding-up.

(§ 1, Ord. 917, eff. February 26, 1991)

SLOPE DENSITY/LOT AREA FOR RESIDENTIAL PROPERTIES TABLE 4C

The Table of R-1 H (Hillside Density District) Parcels, referred to as Table 4D, lists the maximum allowable number of dwelling units for the corresponding parcels of land for properties with an R-1 H zoning designation. Additional units shall be permitted in conformance with State law pursuant to Chapter 4 (Housing Developments Under Government Code Section 65852.21) and Chapter 6 (Accessory Dwelling Units).

(§ 1, Ord. 917, eff. February 26, 1991, as amended by § 3, Ord. 1044 (part), eff. July 28, 2005; Ord. No. 1159, § 10, 12-14-2021; Ord. No. 1160, § 10, 12-14-2021)

TABLE OF R-1-H (HILLSIDE DENSITY DISTRICT) PARCELS for 06/28/05 TABLE 4D

1. MAXIMUM ALLOWABLE NUMBER OF UNITS FOR THE CORRESPONDING PARCELS

(Ord. No. 1159, § 10, 12-14-2021; Ord. No. 1160, § 10, 12-14-2021)

The Table of Maximum Adjusted Floor Area for Properties Located Above 150 Mean Sea Level Elevation, referred to as Table 4E, lists the maximum adjusted floor area allowed on residential properties located above 150 mean sea level elevation.

(§ 1, Ord. 917, eff. February 26, 1991, as amended by § 2, Ord. 976, eff. July 10, 1996, § 2, Ord. 1033, eff. July 24, 2003, and § 3, Ord. 1044 (part), eff. July 28, 2005; Ord. No. 1159, § 11, 12-14-2021; Ord. No. 1160, § 11, 12-14-2021)

TABLE OF MAXIMUM SIZES OF DWELLINGS ON RESIDENTIAL PROPERTIES LOCATED ABOVE 150 MEAN SEA LEVEL ELEVATION TABLE 4E Notes:

(Ord. No. 1115, § 8, 2-28-2017; Ord. No. 1133, § 2, 3-12-2019; Ord. No. 1144, § 2, 4-14-2020; Ord. No. 1159, § 11, 12-14-2021; Ord. No. 1160, § 11, 12-14-2021)

a. Introduction. The "small town" feel and character of San Anselmo's neighborhoods are unique and important qualities to the Town. The existing scale of architecture, the open and tree-covered hills, winding creeks, and landscaped streets and yards contribute to this ambience and to the beauty of a community in which the man-made and natural environments co-exist in harmony.

b. Intent. This Section is intended to accomplish the following:

1. Preserve the quality of life and small town character in the neighborhoods of San Anselmo by limiting the size of new or renovated dwellings and improvements. This size limitation shall be accomplished by establishing a ratio between floor area and lot size and a ratio between lot coverage and lot size. Additionally, this limitation will be accomplished through the establishment of an overall maximum limit on floor area of 5,000 square feet for any residential structure.

2. Provide an additional tool to ensure that homes too big for the lot are neither approved nor built. To manifest such intent, projects should be designed, evaluated and approved based on their compatibility with the neighborhood in which such projects propose to be constructed by being appropriately sized, massed and scaled.

3. Provide a standard that serves to protect property values through the preservation of neighborhood character.

c. Definitions. For the purpose of this Section, the following definitions apply:

1. "Floor area ratio (FAR)" means the ratio between the total floor area of a building or buildings located on a lot and the area of that lot in gross square feet.

2. "Total floor area" means the sum of the gross horizontal areas of all floors of a building measured from the exterior framing of the outside walls.

3. "Adjusted Floor Area" is the total floor area (as measured from the exterior framing of the outside wall), of any dwellings or improvements on a lot, including Basements, Attics with floors, Accessory Dwelling Units and Accessory Buildings. The floor area of interior spaces with ceilings of more than fifteen (15) feet in height from floor to ceiling shall be double-counted in the calculation of Adjusted Floor Area. Adjusted Floor Area excludes the following:

a. Unenclosed Horizontal Surfaces

b. Unenclosed Balconies

c. Unenclosed Decks

d. Unenclosed Porches

e. Crawl Spaces with Dirt Floors

f. Attics with no Floor

g. The first 400 square feet of Garage Floor Area

4. "Adjusted Lot Coverage" is the land area covered by all buildings and improvements on a lot with a finished height above grade of three (3) feet or more, including all projections. Adjusted Lot Coverage excludes the following:

a. Roof eaves which project less than two (2) feet from the face of a building; and

b. Structures and improvements less than three (3) feet above grade.

5. "Attic" means an open space at the top of a dwelling situated wholly or partly within the roof.

6. "Basement" means an enclosed space, finished or unfinished, partly or wholly below natural grade, having more than one-half (1/2) its height, as measured from its floor, whether finished or unfinished, to its ceiling, whether finished or unfinished, below the adjoining natural grade.

7. "Crawl Space" means a shallow, unfinished space, located below the living quarters of a basement-less house and enclosed by the foundation walls, where it is not possible for an adult to stand.

8. "Unenclosed" means a space with or without a permanent roof that is not enclosed by walls, windows or doors on at least two sides. Insect screening would not constitute enclosure.

d. Maximum Adjusted Floor Area and Maximum Adjusted Lot Coverage. Table 4F provides the maximum Adjusted Floor Area and maximum Adjusted Lot Coverage of structures and improvements on lots in the R-1 zoning district located below one hundred fifty (150) feet Mean Sea Level (flatland).

e. Maximum Adjusted Floor Area Exception. The maximum Adjusted Floor Area may be exceeded on a lot by up to 325 square feet subject to Design Review approval pursuant to Article 15 of this chapter. Additional floor area is not allowed for any lots or structures associated with an application under Title 10, Chapter 4 or California Government Code Sections 65852.21 and 66411.7, unless required to accommodate two (2) eight hundred (800) square foot units. (Ord. No. 1133, § 3, 3-12-2019)

(Ord. No. 1158, § 3, 11-9-2021; Ord. No. 1159, § 12, 12-14-2021; Ord. No. 1160, § 12, 12-14-2021)

Table of Maximum Sizes of Dwellings on Single Family Residential Properties Located Below 150 Mean Sea Level Elevation Table 4F

Note:

(1) Subject to Findings per Sec. 10-3.412(e)

(2) Additional floor area is not allowed for any lots or structures associated with an application under Title 10 Chapter 4 or California Government Code Sections 65852.21 and 66411.7.

(Ord. No. 10-66, 11-9-2009)

(Ord. No. 1115, § 9, 2-28-2017; Ord. No. 1159, § 13, 12-14-2021; Ord. No. 1160, § 13, 12-14-2021)