That portion of a building that is partly or completely below grade. No basement shall extend beyond the footprint of the ground floor in order to increase its area. (See also "story above grade.")

The vertical distance from the average elevation of the finish grades, taken at the four corners of the building, to the highest point of the roof. Except as otherwise provided in this chapter, no appurtenant structures or mechanical devices, other than chimneys and flues, shall be permitted to extend above the highest point of the roof.

For purposes of calculating floor area, the word "cellar" is synonymous with "basement." No cellar shall extend beyond the footprint of the ground floor in order to increase its area.

An exterior floor system, without a roof, supported on at least two opposite sides by an adjoining structure and/or posts, piers or other independent supports, attached to a building structure.

For purposes of calculating height/setback ratio:

Any horizontal structure intended to support loads.

The sum of the horizontal areas of the floors in each story of a building or buildings (having a floor or floors) measured from the exterior of the outside walls of such building or buildings without exclusion of any areas on the floors being measured whatsoever (i.e., including attached garages at or below grade, attics over one-story areas where the height from the joist to the underside of the ridge is greater than five feet, any basements that are considered a story above grade, closets, bathrooms, stairwells and other open areas, enclosed porches, and all accessory buildings), except that basements shall be excluded. Further, for horizontal areas where the floor to ceiling height is 14 feet or greater, twice the horizontal area shall be included, and for horizontal areas where the floor to ceiling height is greater than 10 feet and less than 14 feet, 1 1/2 the horizontal area shall be included. This applies whether or not a second floor structure exists.

A ratio which produces the proportion of maximum allowable floor area to total lot area.

For purposes of measuring the building height and for calculating the height/setback ratio, grade is the finished grade, as defined in § 271-7, elevation from which the height of a building or structure is measured.

One of the criteria used in setting building and construction limitations on a residential lot. It is a ratio which produces an inclined plane beginning at a property line rising towards a principal building or structure, starting at a vertex elevation point. Except as otherwise provided in this chapter, no appurtenant structures or mechanical devices, other than minor architectural features not covering more than 10% of the roof area, such as chimneys, flues, skylights and dormer windows, shall be permitted to extend above the inclined plane of the height/setback ratio. A demonstration of a height/setback ratio measurement is shown below as Figure No. 1.[1]

The total horizontal area within the property lines and or lot lines of a plot.

A legal boundary of a lot.

Any ground area covered by concrete, brick or other impervious material, excluding walkways 48 inches or less in width, which is without a roof structure and not elevated above the surface of the ground in any matter. Patios do not include driveways in front yards.

Any open-sided roofed structure, without screens or other enclosures, attached to the outside of a building.

Any nonconditioned, roofed structure, enclosed with screens or other similar enclosures, attached to the outside of a building.

Any open-sided roofed structure, without screens or other enclosures, attached to the entrance of a building.

Any lot line dividing a lot of one owner from a lot of different owner.

Any story having its finished floor surface entirely above grade, except that a basement shall be considered as a story above grade where the finished surface of the floor above the basement is: more than six feet above grade plane; or more than six feet above the finished ground level for more than 50% of the total building perimeter; or more than 12 feet above the finished ground level at any point.

Any highway or thoroughfare which affords the principal means of access to abutting properties, whether designated as a street, avenue, road, crescent, lane, terrace, way, place or otherwise, and whether public or private.

The dividing line between a lot, tract or parcel of land and a contiguous street. For purposes of this chapter, a street line and a right-of-way line are the same.

Any change in the supporting members of a building, including but not limited to bearing walls or partitions, columns, beams, headers or girders or any substantial change in the roof or in the exterior walls.

Any construction or combination of materials or any production or piece of work artificially built up or composed of parts joined together in some definite manner, including but not limited to play structures (but excluding basketball hoops, basketball nets and basketball backboards, whether mounted on a building or on poles, so long as the height of the top of the backboard does not exceed 16 feet and there is not more than one backboard on the premises), platforms, pools, tennis courts (including the backstops, surfaced area and net posts thereof), radio towers, parabolic or hemispheric discs or dishes or other similar convex or concave antennas (the purpose of which is to receive television, radio and/or microwave or other similar signals from satellites or ground stations which transmit satellite signals, but excluding conventional television and radio aerials), sheds, fences, walls and display signs.

A yard extending the full width of the lot opposite (and approximately parallel to) the principal front yard between the main building and the rear lot line, unless said yard would otherwise be a secondary front yard. A rear yard may abut a street or right-of-way when the lot has a front and/or a secondary front yard.

All front yards that are not principal front yards.

All yards between the main building and the lot lines that are not front yards or rear yards.