Columbia Dimensional summary table ordinance (§ 29-4.1)

(a) General dimensional standards. The following Tables 4.1-1 to 4.1-3 state the dimensional standards for residential, mixed use, and special purpose districts contained in chapter 29-2 (zoning districts). In case of a conflict between the dimensions shown in this section 29-4.1 and the dimensions shown for individual districts in chapter 29, article 2, the provisions of this section 29-4.1 shall apply. In each table, a blank cell indicates that there is no standard for that dimension or measurement. (See section chapter 12A of the City Code for additional required building setbacks from stream corridors. See section 29- 4.1(b)(2) (solar orientation density bonus), section 29-4.1(b)(3) (rural cluster density bonus), and section 29-4.1(b)(8) (substandard lots) for additional information related to dimensional standard reductions and bonuses).

Table 4.1-1: Dimensional Standards for Residential Districts

District

Standard R-1 [6] R-2 [1] R-MF [2] [6] R-MH

Current [6] Cottage

Lots

Minimum Lot Area (sq. ft.)

One-Family Dwelling 7,000 5,000 3,000 5,000 3,750

One-Family Attached Dwelling 3,500 3,500

Two-Family Dwelling 7,000 7,000

Multiple Family Dwelling 2,500 per du

Sorority or Fraternity 7,500

CRCC No min., but max. density

17 du/ac

Lot area if no public or community sewer [5] 15,000 15,000

Minimum Lot Width (ft.) (detached) 60 60 30 60 45

Minimum Lot Width (ft.) (attached) - per lot 30 30

Minimum Setbacks (ft.)

Front Yard

Front Yard Depth 25 25 10 25 20

Front lot line to garage depth (if applicable) 25 25 20

Side Yard

Side Yard 6 6 6 6 or 10[7] 10

Side Yard - Corner Lot Street Side 25 25 10 15

Distance between mobile dwelling units 20

Rear Yard Lesser of Lesser of 10 25 10

30% lot 25% lot depth or depth or 25 25

Maximum Height (ft.)

Primary Residential Building 35[3] 35[3] 35 35[3] 35 See also section 29-4.7 Neighborhood Protection Standards

Primary Non-residential Building [4] 75 75 75 See also section 29-4.7 Neighborhood Protection Standards

[1] All R-2 lands are subject to Current Standards until they request application of the Cottage Standards, and that request is approved under section 29-6.4(j).

[2] Multifamily structures constructed before January 1, 2014, with building height up to 45 ft. and lot area of at least 1,500 sq. ft. per dwelling unit are conforming structures.

[3] Or 45 ft. if two side yards at least 15 ft. in width are provided.

[4] Provided that each building setback is increased one foot above the District residential building minimum for each one foot of additional building height above the residential building maximum.

[5] The minimum lot area for on-site septic is subject to health department approval based, in part, on distances between the lot and existing public sewer mains. This lot area could be greater, conditional, or denied on a case-by-case basis. [6] "Substandard lots" meeting the definition and qualifications specified in section 29-1.11 may nonetheless be eligible for a single-family building permit subject to the dimensional standards of section 29-4.1(b)(8).

[7] The minimum side yard setback for single-family (detached and attached) and two-family dwellings shall be six ft. Multi-family structures (3 or more units) minimum side yard setback shall be 10 ft.

Table 4.1-2: Dimensional Standards for Mixed Use Districts

District

Standard M-OF M-N [1] M-C [2] M-BP M-DT

Current Pedestrian Current Transit

Lots

sdradnatS lanoisnemiD TD-M rof 2.4-92 noitces eeS Minimum Lot Area (sq. ft.)

Lot Area 0 0 0 0 0 0

Lot Width at Building Line[3] 0 0 0 0 0 0

Building Setbacks (ft.)

Front Yard

General Min. 25 Min. 25 Min. 0 Min. 25 Min. 0 Min. 15

Max. 10 [4] Max. 10 [4]

From Arterial and Collector Streets Min. 25 Min 25 Min. 0 Min. 25 Min. 0 Min. 25

Max. 10 [4] Max. 10 [4]

Side Yard

General Min. 0 Min. 0 Min. 0 Min. 0 Min. 0 Min. 0

Adjacent to R District Min. 10 Min. 10 Min. 10 Min. 20 Min. 20 Min. 20

Corner Lot with Frontage on Min. 15 Min. 15 Min. 0 Min. 15 Min. 10 Min. 25 Arterial or Collector Street

Corner Lot with Frontage on Other Min. 15 Min. 15 Min. 0 Min. 15 Min. 10 Min. 20 Streets

Rear Yard

General Min. 25 Min. 0 Min. 0 Min. 0 Min. 0 Min. 0

Adjacent to R District Min. 10 Min. 10 Min. 20 Min. 20 Min. 20

Maximum Height (ft.)

Primary Building 45 35 35 45 55 45 See also section 29-4.7 Neighborhood Protection Standards

[1] All M-N lands are subject to Current Standards until they request application of the Pedestrian Standards and that request is approved under section 29-6.4(j).

[2] All M-C lands are subject to Current Standards until they request application of the Transit Standards, and that request is approved under section 29-6.4(j).

[3] If direct driveway access is proposed to lots fronting collector or arterial streets see section 29-5.1(f)(1)(iv)(d). [4] 75% of building frontage width must be located between minimum and maximum setback distances.

Table 4.1-3: Dimensional Standards for Special Districts

District

Standard IG A O

Lots

Minimum Lot Area (ac.) 2.5 2.5

Minimum Lot Area For Private Open Space (sq. ft.) 7,000

Minimum Lot Width at Building Line (ft.) 60 60

Minimum Setbacks (ft.)

Front Yard 25 25 25

Side Yard - General 0 25 25

Side Yard - Adjacent to R District 20

Rear Yard - General 10 25 25

Rear Yard - Adjacent to R District 20

Maximum Height (ft.)

Primary Building 35 35 See also section 29-4.7 Neighborhood Protection Standards

(b) Special dimensional standards or measurements.

(1) Median front yard for multiple lots.

(i) In the R-1, R-2, and R-MF districts, where the nearest lots on either side of a residential lot have been developed with residential structures, the median of the front yards of such residential buildings shall establish the minimum front yard depth for the subject lot. In no case shall the setback be less than the minimum setback established in Table 4.1-3 unless a reduction is approved by the board.

(ii)

Where a recorded plat has been filed showing a setback line that otherwise complies with the requirements of this chapter, but is less than the established setback for the block as provided above, the setback line shown on the plat shall apply.

(2) Solar orientation density bonus.

(i) A subdivision in the R-1 or R-2 districts in which at least seventy-five (75) percent of lots are created on blocks where the longer dimension of the block is oriented within fifteen (15) degrees of true east-west in order to increase potential solar gain, the maximum number of single-family or two-family lots permitted on the parcel under Table 4.3-1 shall be increased by ten (10) percent above the number of lots permitted, and the minimum size and width of each lot shall be reduced by fifteen (15) percent below the minimum lot size and width required if the streets had not been so aligned.

(ii) In a subdivision that meets the requirements for application of the solar orientation density bonus, the minimum lot size and lot width in the R-1 or R-2 districts shall be adjusted to allow the parcel to contain ten (10) percent more lots greater than if the streets had not been so aligned.

(3) Rural cluster density bonus.

(i) A subdivision in the R-1 or R-2 districts that preserves at least fifty (50) percent of the gross land area of the parcel in open space protected from future development shall be allowed to include ten (10) percent more residential lots than if such land had not been designated for protection.

(ii) In order to earn a density bonus, the lands protected from development shall meet the following requirements:

(A) The calculation of protected open space shall not include any lands designated as floodway or flood fringe in the FP-O floodplain overlay;

(B) The protected lands shall include any lands designated as sensitive lands on the land analysis map required by section 29-5.1(b) to the greatest degree practicable;

(C) The protected lands shall be designed to be contiguous to any protected lands on adjacent subdivided lands to the greatest degree practicable;

(D) The applicant shall record in the real property records of Boone County a restrictive covenant, in a form acceptable to the city counselor, or designee, preventing future development of the protected lands in perpetuity, and demonstrating that a homeowners association or other entity has accepted responsibility for maintenance and management of the protected lands and has legal authority to collect funds from homeowners or others adequate to pay the expenses of such maintenance and management.

(iii) In a clustered subdivision that meets the requirements for application of the rural cluster density bonus, the minimum lot size and lot width in the R-1 or R-2 districts shall be adjusted to allow the parcel to contain ten (10) percent more lots greater than if fifty (50) percent of the gross land area had not been protected from development.

(iv)

The rural cluster density bonus may be combined with the solar access density bonus in section 29-4.1(b)(2).

(4) Rear yards.

(i) No rear yard shall be required in any nonresidential district on any lot of which the rear lot line adjoins a railway right-of-way or which has a rear railway track connection.

(ii) In computing the depth of a rear yard for any building where such yard abuts an alley, one-half of such alley may be assumed to be a portion of the rear yard.

(iii) The standards in subsections (i) and (ii) do not apply in the M-DT district (section 29-4.2), which has separate provisions for measuring building rear setbacks.

(5) Official major roadway plan. The major roadway plan shall be prepared by CATSO and submitted to the commission for recommendation and adoption by the council. Once a major roadway plan has been adopted by council, where a line on the major roadway plan (MRP) indicates that street widening has been planned right-of-way shall be reserved for future widening or opening of a street upon which a lot abuts, and the depth or width of a yard shall be measured from the MRP line to the nearest line of the building. The board may vary the setback lines established in conformance with the major roadway plan if it determines that unwarranted hardship, which constitutes an unreasonable deprivation of use as distinguished from the mere grant of a privilege, may be avoided.

(6) Detached accessory structure.

(i) In any residential district, a detached accessory structure shall not:

(A) Exceed twenty-four (24) feet in height;

(B) Be higher than the main building; or

(C) Occupy more than thirty (30) percent of a rear yard.

(ii) A detached accessory structure may be connected with the main building by a breezeway, open on each side, not more than six (6) feet wide, the roof of which is not more than twelve (12) feet high at its highest point, and is not an extension of the roof of the main building.

(7) Higher education institution buildings. Buildings constructed on the campus of an institution of higher learning, and that have been included as part of a development plan approved by the council, need not comply with the yard requirements of the district in which they are located, but shall comply with the following requirements:

(i) Minimum distance between the building and a street line is twenty-five (25) feet; and

(ii) Minimum distance to a property line other than a street is fifteen (15) feet for buildings thirty-five

(35) feet or less in height, and five (5) additional feet for each additional ten (10) feet or part thereof in height.

(8) Substandard lots. If a lot, parcel, or tract of land zoned R-1, R-2, or R-MF meets the definition of "lot, substandard" and has been determined to be a "lot," as such terms are defined within section 29- 1.11, such lot, parcel, or tract shall be entitled issuance of a building permit for a single-family dwelling provided the following minimum dimensional standards are met:

Lot Area (sq. ft.)

Minimum lot area - all districts 3,000

Lot Width (ft.)

Minimum - all districts 30

(c) Exceptions and encroachments.

(1) Height. Table 4.1-4 identifies exceptions to those height limits shown in section 4.1(a) and (b) above.

Table 4.1-4: Height Exceptions

Structure, Feature, or Use Maximum Height (ft.) Conditions or Limits

Elementary/Secondary schools in R-MF 100 district

■ Parapet walls

■ False mansards

■ Flagpoles

■ Chimneys

■ Finial cooling towers

■ Elevator bulkheads

■ Penthouses

6 feet above maximum height limit of district

■ Stacks

■ Cupolas

■ Antennas

■ Spires, and

■ Rooftop solar energy equipment

■ Rooftop HVAC equipment screened by parapet wall

Rooftop or yard mounted WECs equipment 30 ft. above maximum height limit in district in M-BP or IG district

Agricultural uses (e.g. silos, windmills, barns, 75 feet etc.) in A-1

Radio and television antenna (private, 45 feet Must not be located in front yard, and must noncommercial) in residential districts comply with all other applicable laws and

ordinances.

(2) Yard areas. Table 4.1-5 identifies exceptions and encroachments to required yard areas. Except for permitted exceptions in the table, every part of a required yard or court shall be open and unobstructed from its lowest point to the sky.

Table 4.1-5: Yard Area Exceptions Structure, Feature, or Use Yard Encroachment (maximum) Conditions or Limits

Building sills, belt courses, cornices, 2 ft. into a yard chimneys, buttresses, ornamental features, eaves, and rain barrels Canopies or open porches 6 feet into front or rear yard Roof area limited to 60 sf or less; Porch cannot be

enclosed Driveways Single- and Two- Up to a 2-car Permitted to a maximum width of 20 Single- and two-family residential driveways shall

Family Residential garage ft. in any front, rear, side, or corner maintain a setback of 5 ft. from the side property line side yard and shall not occupy more than 50% of the lot width. 3-car garage Permitted to a maximum width of 28 ft. in any front, rear, side, or corner side yard Shared duplex Permitted to a maximum width of 36 driveway ft. in any front, rear, side, or corner side yard Multi-Family, Permitted to a maximum width of 42 ft. without a Multi-family, commercial, and mixed-use driveways Commercial, and turning analysis, in any front, rear, side, or corner side shall maintain a setback of 10 ft. from any side property Mixed-Use yard line adjacent to a Residential district, or as determined by the required driveway radius. Lot boundary fences, walls, and Permitted up to lot line May not encroach on public right-of-way or adjacent retaining walls property without consent of owner Open fire escape Into side yard, by no more than ½ the side yard width Cannot extend more than 4 feet from the building Open paved terraces 10 feet into front or rear yard Solar or geothermal energy Permitted in a side or rear yard Not within 2 feet of a side or rear property line equipment