| Home > Zoning Ordinance > Glossary of Zoning Terms |  |
Glossary of Zoning Terms
Accessory Building: A structure, designed for the shelter or enclosure of persons, animals or property of any kind that is customarily associated with, incidental and subordinate to the principal building on the lot. An example may be a detached garage, shed, or doghouse.
Accessory Structure: Any combination of materials that have a permanent location on the ground that is physically detached from, secondary and incidental to, and commonly associated with the primary structure. An accessory building is a type of accessory structure but an accessory structure is not necessarily a building. Examples on non-building accessory structures include a fence, air conditioning units, play equipment, and decorative yard ornaments.
Accessory Use: An activity on a lot that is customarily associated with, incidental and subordinate to the principal use on the lot. Accessory uses may include home-based businesses (to a residential use), on-site sales (in addition to manufacturing activities), and day care centers (to residential or commercial uses).
Amenity Development Option: A proposed special development option to be incorporated into the zoning revision. This alternative development option will provide a broader range of development alternatives (beyond underlying zone requirements of height, bulk, setback, etc. requirements) to land developers in exchange for provisions of additional community benefits (added parkland, open space, etc.), over and above what is regulated.
Buffer: A strip of land that physically separates two or more different land uses or lots by providing space between the two uses or lots. A screen may or may not be located on a buffer.
Building: A structure having one or more stories and a roof, designed primarily for the shelter, support or enclosure of persons, animals, or property of any kind. Buildings include houses, office buildings, barns, garages, and sheds.
Building, Main: A building in which is conducted the principal use of the lot on which it is located. In a residential zone, any dwelling is deemed to be a main building on the lot on which it is located.
Commercial Green Area: In the current ordinance, this term is used to mean an area of land associated with and located on the same tract of land as a major building or group of buildings in relation to which it serves to provide light and air, or scenic, recreational or similar purposes. Such space is available for use by the occupants or users of the building, but may include a limited proportion of space so located and treated as to enhance the amenity of the development by providing landscaping features, screening for the benefit of the occupants or those in neighboring areas, or a general appearance of openness.
Competing Policy: The balancing of land use and regulatory priorities in the zoning revision. Where there is no state standard or local plan to reference, competing policy means determining which development priorities should weigh more heavily in land use decisions. For example, competing policy includes a decision to streamline zoning regulations. In other situations, competing policy means determining development priorities. For example, in a development plan, to provide an ideal sidewalk width, trees may need to be cut down. Competing policy discussions address these issues.
District: See Zone.
Dwelling: A building or portion of a building arranged or designed to provide living facilities for one or more families. By regulation, the inclusion of a stove or range in a room or set of connected rooms constitutes a dwelling unit. Dwellings may be further identified as one-family, multiple-family semi-detached, or attached.
Euclidean Zone: A method of dividing a community by zones characterized by 1) prioritization of use regulations and 2) inclusion of proscriptive rules (what the jurisdiction does not want to see). Euclidean zoning has been the trend of land use regulations for most of the last century in Rockville and throughout the country. This conventional zoning has produced patchwork quilts of single-use districts (only residential uses allowed or only commercial uses), often with minimal connections (vehicular, pedestrian, or visual) between neighboring zones. The term is derived from the 1926 Supreme Court case of Town of Euclid, Ohio v. Ambler Realty Company, which established the right of communities to separate uses into zones.
Family: An individual, or two or more persons related by blood or marriage, or a group of not more than five persons (excluding servants) not related by blood or marriage, living together as a single housekeeping group in a dwelling unit. (Note: The is the current definition in the Rockville Zoning Ordinance.)
Floating Zone: Floating zones are the same in content as a conventional zone (regulating use, bulk, area of buildings) but are not mapped until approved. When approved, the zone is “brought down to earth” to be affixed to a particular parcel through amendments to the zoning map. These zones allow for locating use types which cannot be anticipated, or uses for which the City would like to encourage, but for which a City cannot currently say where they should be located. Floating zones normally have a special set of requirements and limitations to assure compatibility with the surrounding neighborhood. They may also be subject to a design review process by the City to further insure that the compatibility requirements are met.
Forest: A dense growth of trees, together with other plants, covering a large area. According to the Forest and Tree Preservation Ordinance of the City of Rockville, a forest must cover a land area of 10,000 square feet or greater.
Form Based Zoning: A method of land use regulation characterized by 1) emphasis on form regulations (building size, location, appearance) and 2) prescriptive rules (what a community does want to see built). Form based zoning focuses on established bulk regulations to solve the Euclidian “problem” of use separation. Form codes are designed to provide more flexibility than conventional codes to promote development in largely built out communities. These codes work well in established communities because they effectively define and codify a neighborhood's existing characteristics or they can implement new building types when a radical change is desired.
Grandfathering: In instances where existing development would become nonconforming as a result of changes in the zoning regulations, a use or structure may be allowed to continue as a conforming use through special provisions of the ordinance.
Green Requirements: Those regulations in a zoning ordinance (open space, impervious surface limitations, screening and landscaping requirements) that mandate that the land have some vegetative cover versus some manmade covering (buildings, asphalt, cement, etc.).
Greenfield Development: Construction on undeveloped lands such as forests or farms.
Impervious Surface: A surface that does not permit the absorption of fluids. As a land use term, impervious surface means any surface such as roads, rooftops, patios, or parking lots that does not allow water to soak into the ground. Impervious surfaces result in runoff from the surface in greater quantities and/or an increased rate when compared to natural conditions prior to development.
Infill: Developing on an empty lot(s) of land within an otherwise developed area of the City. Infill development fills a void between two existing structures.
Landscaping: Some combination of grass, trees, hedges, shrubs, ground covers or flowers planted and maintained to enhance the appearance of a development including, but not limited to, walks, fountains, reflecting pools, art works, screens, walls, fences, and benches. Landscaping may be located in or outside a buffer though it is not considered part of a forest, streamvalley, or stormwater management area.
Lot: A plot of land developed or to be developed. A lot may or may not be occupied by a building and its accessory buildings or by group dwellings and their accessory building(s), together with open spaces. A record lot (or recorded lot) is a lot that has been legally recorded as part of a subdivision plat filed in the County land records. In general, in order to obtain a building permit, the property must be a record lot.
Lot, ownership: A lot shown on a subdivision plat, which designates land as separate lots only for purposes of ownership identification. An ownership plat does not create formal individual subdivided lots.
Main Building: See Building, Main
Mansionization: The process where single-family, detached homes are demolished or enlarged to create houses that are several times larger than the originals and which create structures that are out of proportion with the surrounding houses. Rising real estate values, convenient locations, and a desire for added in-home amenities all contribute to this process.
Mixed-Use: The development of a lot, or designation of a zoning district that provides for more than one classification of activities (i.e. allowing residential, commercial, and/or office uses within the same building or within the same district).
Nonconforming Development Standard: The dimensions of a lot, or a building, structure, or other lot feature (such as, but not limited to, parking, lot coverage, green space, etc.) located on the lot that was lawful when established but no longer conforms to the requirements of the zone in which it is located as set forth in the Zoning Ordinance, because of adoption of a zoning amendment or comprehensive zoning revision. The term “nonconforming development standard” is a broad category and can apply to 1) a nonconforming lot, 2) a nonconforming structure, and 3) a nonconforming lot feature. There are particular considerations with regard to each type of development standards.
Nonconforming Use: The activity in a building, structure or on land lawfully existing immediately prior to the effective date of the current zoning ordinance, as may be amended, which no longer permitted in the current zone. A nonconforming use may be continued, but not expanded. If it ceases for a period of 3 months, it cannot be reinstated. Any future use must comply with the current zoning standards.
Open Space: A portion of a lot that is set aside for public or private use and will not be developed. The space may be used for passive or active recreation, or may be reserved to protect or buffer natural areas.
Optional Method: These procedures allow for large tracts of land, under a single ownership, to be developed in a manner particular to that tract of land. These methods of development are an alternative to the existing zone requirements on that lot. In essence, these options allow a developer to design a project for a tract of land using development standards (such as building height, setback, and lot coverage requirements) unique to the project, within given boundaries, so long as they meet the prescribed approval process and the established goals of the City provided for that type of development option.
Overlay District: An area of a City where additional regulations are applied to the underlying zoning regulations in order to protect certain features or to encourage a particular type of development. (Imagine a blanket covering a couch. The couch is still there but you also have the blanket too.) Overlay districts may cover all or part of one or several traditional zones. Districts are designated on a zoning map. Where there is a conflict between overlay and underlying zoning standards, the overlay standards will apply because they are stricter. The most common overlay districts in Rockville are historic districts.
Park: A piece of open land for active or passive recreation use in an urban area.
Performance Zoning: This form of land use regulations applies a more “hands off” approach for government. Performance regulations control the intensity of the land use, not the use itself and not the building size, shape, or dimensions. Common performance regulations include limiting the hours of operation, prohibiting shadow casting of buildings at certain times, and noise level regulations.
Planned Development Option: One of two proposed special development options to be included in the zoning ordinance revision. This will be a compilation of the several existing development options in the current ordinance. Under the proposed regulatory scheme for the new Planned Development Option, there would be only one approval process (instead of the multiple approval schemes currently in the ordinance). Requirements for approval, however, may vary based on the type of development proposed. Different standards may be included for residential versus mixed use, and/or Greenfield versus redevelopment.
Public Areas: Land that is owned and controlled by a government agency (i.e. federal, state, regional, county or municipal jurisdiction) and that is available for use by the general public. This includes publicly owned parkland.
Screen: The physical separation (visual barrier) of two or more different land uses or lots typically by landscaping (with evergreen plants), fences, or walls that create a barrier between uses or lots.
Special Exception: A special exception is a use that is allowed in a zoning district, provided the use complies with a specified set of requirements and is found compatible with the surrounding neighborhood. The standards and requirements for these uses is set forth in the zoning ordinance. The Board of Appeals administers special exceptions.
Subdivision: The division of a lot, tract, or parcel of land into two or more lots, plats, sites, or other divisions of land for the purpose of building development. Subdivision also includes the assemblage of several lots or parcels into one lot. Approval of a subdivision requires the recording of a plat among the County land records. The Planning Commission administers the subdivision process.
Treelawn: The strip of land between the street and the sidewalk where trees are planted.
Urban Design: The process of providing a design vision for the City or portions of the City. Urban design encompasses architectural treatments, landscaping, pedestrian circulation and traffic controls to provide a pleasant, harmonious, and livable public realm.
Variance: A variance is a modification of the density, bulk or area requirements of the zoning ordinance. A variance may be granted if the property owner can demonstrate that, because of conditions peculiar to the property not imposed by the owner, literal conformance will result in practical difficulty. The granting of a variance must not be contrary to the public interest. The Board of Appeals administers variances.
Vegetative Covering: A requirement to have soil, plant life or other natural feature within an area instead of any man-made surface or construction.
Zone: A geographical region of a City characterized by some distinctive feature(s) or characteristics as determined through the City’s land use regulations. Also known as a district.
Zoning: The division of a city into areas (zones) regulating the character of the development allowable in each zone. Common zoning regulations include, but are not limited to, those for the 1) use of the land or building on the land, 2) shape of a building, 3) location of a building on a lot, 4) landscaping requirements, 5) signage regulations, and 6) parking regulations.
Zoning Ordinance: The portion of the City’s Code that establishes the type and amount of development that is permissible in the specific zoning districts and which also establishes other development controls. The current zoning ordinance is codified as Chapter 25 of the Code of the City of Rockville.