(A) Statement of purpose. The principal purposes of the zero lot line concept are:
(1) The more efficient use of land, as compared with the typical single-family development, making available needed housing at a more affordable cost;
(2) The design of dwellings that integrate and relate internal-external living areas resulting in more pleasant and enjoyable living facilities; and
(3) By placing the dwelling against one of the property lines, permitting the outdoor space to be grouped and utilized to its maximum benefit.
(B) Permitted districts.
(1) A zero lot line development for single-family attached and single-family detached dwellings are permitted by right in an R-3, R-4 and R-5 residential district, in accordance with the provisions of this section.
(2) A zero lot line development for single-family attached or single-family detached dwellings is permitted in an EST-l, R-1 or R-2 zone upon the issuance of a conditional use permit by the Board of Zoning Adjustment.
(C) Permitted uses. The following uses are permitted:
(1) Single-family detached and attached dwellings;
(2) Two-family or duplexes; and
(3) Accessory buildings and structures provided no such building or structure shall be designed or used for dwelling purposes.
(D) Standards.
(1) Building site area. Each lot shall have an area not less than 3,500 square feet.
(2) Building site width. The minimum building site width at the building setback line shall be 20 feet.
(3) Building site coverage. The total lot coverage permitted for all buildings on the site shall not exceed 50% of the lot area.
(4) Building height limit. The maximum building height shall not exceed two stories or 35 feet in height.
(5) Setback requirements.
(a) Interior side yard. The detached dwelling unit shall be placed on one interior side property line with a zero setback and the dwelling unit setback on the other interior side property line shall be a minimum of ten feet, excluding the connecting elements such as fences, walls and trellises. Patios, pools, garden features and other similar elements shall be permitted within the ten-foot setback area; provided, however, no structure, with the exception of fences or walls, shall be placed within easements required by this section.
(b) Interior side yard. The attached dwelling unit shall be placed on the interior side property line with a zero setback and the dwelling unit setback on the other interior side property line can also be placed on the property line with a zero setback.
(c) Exterior side yard. The dwelling unit shall be placed ten feet from all exterior property lines.
(d) Front setback. All dwelling structures shall be set back a minimum of 25 feet from the front property line.
(e) Rear setback. The required rear setback is ten feet.
(f) Side street setback. The dwelling setback shall be a minimum of 15 feet from the side street property line.
(E) General requirements.
(1) Platting requirements. Each dwelling shall be located on its own individual platted lot. If areas for common use of occupants of the developments are shown on the plat, satisfactory arrangements shall be made for the maintenance of the common open space and facilities as provided in division (E)(8) below. The plat shall indicate the zero lot lines and easements appurtenant thereto.
(2) Openings prohibited on the zero lot line side. The wall of the dwelling located on the lot line shall have no windows, doors, air conditioning units or any other type of openings, provided however, that atriums or courts shall be permitted on the zero lot line side when the court or atrium is enclosed by three walls of the dwelling unit and a solid wall of at least eight feet in height is provided on the zero lot line. The wall shall be constructed of the same material as exterior walls of the unit.
(3) Maintenance and drainage easements. A perpetual four-foot wall-maintenance easement, for detached dwellings, shall be provided on the lot adjacent to the zero lot line property line, which, with the exception of walls or fences, shall be kept clear of structures. This easement shall be shown on the plat and incorporated into each deed transferring title to the property. The wall shall be maintained in its original color and treatment unless otherwise agreed to in writing by the two affected lot owners. Roof overhangs may penetrate the easement on the adjacent lot a maximum of 24 inches, but the roof shall be so designed that water runoff from the dwelling placed on the lot lines is limited to the easement area.
(4) Separation between dwellings on adjacent lots. There shall be a separation between dwellings on adjacent lots of not less than ten feet.
(5) Off-street parking. Each dwelling shall have not less than two off-street parking spaces. Enclosed garages or carports are not required, but if carports or garages are built they must be attached. If carports or garages are to be incorporated in the future the site plan must show the placement of the structures prior to approval by the Zoning Inspector or Planning Commission.
(6) Trees.
(b) In case of development with public roads, the trees may be placed on private lots in lieu of the
public right-of-way provided that 20-foot spacing and the rowing of trees are maintained. This shall be in addition to the three trees required for each platted lot.
(7) Accessory buildings and structures. Accessory buildings and structures shall be subject to the
following requirements.
(a) No such building or structure shall be located within a required front or street-abutting side yard.
(b) No such building or structure shall be located within five feet of a dwelling or another accessory building or structure nor within two feet of any interior property line.
(c) No such building or structure shall exceed ten feet in height without a conditional use permit.
(8) Common open space and maintenance of facilities. Common open space is not required but may be permitted. If common open space is provided, provisions satisfactory to the City Council shall be made to assure that nonpublic areas and facilities for the common use of occupants of zero lot line development shall be maintained in a satisfactory manner, without expense to the general taxpayers of the city.
(9) Open space. There shall be an open space on each lot of not less than 300 square feet with no dimension less than 15 feet. The open space area shall be exclusive of required front and street-abutting side yards and vehicular driveways and further shall be subject to the following.
(a) The required open space may include side or rear yards.
(b) Pools and paved recreational areas may be developed in the required open space.
(c) The gradient or slope of any required open space shall not exceed 12%. The open space may be provided on a deck.
(d) The open space shall be fully open to the sky.
(e) An accessory building may not occupy any part of the required open space.
(F) Site plan review. A site plan review is required to encourage communication between the applicant and the Planning Commission staff. A site plan review will promote a greater degree of logic, imagination, innovation and variety in the design process. The site plan submittal should follow the guidelines as set forth in §§ 158.300 through 158.311.
(Ord. 11-85, passed 12-3-1985; Ord. 13-90, passed 9-4-1990) Penalty, see § 158.999