Land Use Code: Art. 3 Div. 2

ARTICLE 3: DEVELOPMENT REGULATIONS
DIVISION 2. DEVELOPMENT CRITERIA

Printable PDF

Sections

3.2.1 PURPOSE
3.2.2 PRINCIPAL LAND USE
3.2.3 PRINCIPAL STRUCTURE
3.2.4 SECONDARY LAND USE
3.2.5 ACCESSORY USES AND STRUCTURES
3.2.6 PERIMETER YARDS
3.2.7 STRUCTURE HEIGHT MEASUREMENT
3.2.8 ACCESS PROVISIONS
3.2.9 LOT COVERAGE
3.2.10 RESIDENTIAL DENSITY CALCULATIONS
3.2.11 FLOOR AREA RATIO (FAR) CALCULATION
3.2.12 SOLAR CONSIDERATIONS
3.2.13 STREETS
3.2.14 LOTS


3.2.1 PURPOSE. This Division establishes regulations that will be applied uniformly to all uses, in all zones.

3.2.2 PRINCIPAL LAND USE. A principal use is a land use which is allowed in a zone as a Permitted Land Use or as a Special Exception Land Use. The principal use is generally the primary or predominant activity conducted on a parcel; however, two (2) or more principal uses can be located on the same parcel in some zones.

3.2.2.1 One (1) or More Uses, Separate Projects. One (1) or more principal uses which are conducted as separate projects on a parcel are considered individually in determining the respective Land Use Classes and development regulations.

3.2.2.2 Two (2) or More Uses, Same Project. Two (2) or more principal uses conducted as a single project, which integrates elements of the various uses, such as, but not limited to, vehicular parking, vehicular and pedestrian access, refuse collection, and loading services, as common use among the various uses in the project, shall have development requirements applied as follows.

A. Two (2) or More Uses, Same Development Designator. On projects with two (2) or more uses which have the same Development Designator, the Development Designator requirements shall be applied on the site as if there were only one (1) use.

B. Two (2) or More Uses, Different Development Designators. On projects with two (2) or more uses which have different Development Designators, the applicable development requirements shall be based on the floor area ratio (FAR) or residential density (RAC) and the lot coverage (LC) requirements calculated separately for each use. Height and setback requirements for each use shall be in accordance with the requirements of the Development Designator assigned to each use.

1. The total land area of the project site (PS) shall be equal to or greater than the sum of the site areas required for each use. The amount of site area required for each use shall be calculated using the FAR requirement of the use. For each use, the required site area (SA) is equal to the proposed floor area (FA) divided by the FAR, as in the formula (SA = FA ÷ FAR). The total project site area is calculated using the following formula: PS ;o (FA ÷ FAR) + (FA ÷ FAR) + (repeat FA ÷ FAR for each additional use). For additional information on FAR calculations, refer to Sec. 3.2.11.

If one (1) of the uses is a residential use and the residential development is based on units per acre density requirement, the amount of site area (SA), expressed in acreage, required for the number of units proposed is determined by dividing the proposed number of units (U) by the density ratio, residences per acre (RAC), permitted on the property (SA = U ÷ RAC). The site area (SA) for the residential use added to the site area (SA) of the other uses shall be equal to or less than the total project site (PS) area. Formula: PS ;o (U ÷ R) + (FA ÷ FAR) + (repeat FA ÷ FAR for each additional use). For additional information on residential density calculations, refer to Sec. 3.2.10.

2. On lot coverage (LC) requirements, the most restrictive LC requirement applicable to any of the uses in the project which encompasses more than twenty-five (25) percent of the project site gross floor area shall apply on the project site. For more information on lot coverage calculations, refer to Sec. 3.2.9.

Example 1. To determine how much property is needed for a project which has ten thousand (10,000) square feet (sq. ft.) in retail space with an FAR of .35, twenty thousand (20,000) sq. ft. in office space with an FAR of 0.5, and no lot coverage requirement for either use, one must determine how much site area is required for each of the uses. For the retail use site area, using the formula provided above, (SA = FA ÷ FAR) with the FA being 10,000 sq. ft. and the FAR being 0.35, the result (SA), 28,571.43 sq. ft., is the minimum site area required for the retail use. The same calculation is performed for the office use, where the FA is equal to 20,000 sq. ft. and the FAR is equal to 0.5. Once the calculations are complete for each of the proposed uses, the site areas (SA) for each use are added together (28,571.43 + 40,000). The sum, 68,571.43 sq. ft., is the minimum project site size required to accommodate the proposed uses. (See Illustration 3.2.2.2.B. Example 1.)

Example 2. To determine which LC requirement to apply if one (1) of the uses has an LC requirement of fifteen (15) percent and another requires eighty (80) percent, and the use with the fifteen (15) percent LC needs or uses twenty thousand (20,000) sq. ft. of a ninety thousand (90,000) sq. ft. site, one needs to determine if the twenty thousand (20,000) sq. ft. is fifteen (15) percent or more of the ninety thousand (90,000) sq. ft. site. This is determined by dividing the twenty thousand (20,000) sq. ft. by the ninety thousand (90,000) sq. ft. (20,000 ÷ 90,000 = .22). Since the percentage, twenty-two (22), is less than twenty-five (25) percent, the least restrictive of the LC requirements applies to the entire site. (See Illustration 3.2.2.2.B. Example 2.)

3.2.3 PRINCIPAL STRUCTURE. The structure(s) in which the principal use(s) is conducted shall be constructed in compliance with the development regulations listed for the Development Designator assigned to the principal use(s). The Development Designator is shown as a letter symbol for residential development and a number symbol for nonresidential development.

3.2.3.1 Residential Development Designator.

A. Suburban Density Matrix. Development criteria in this matrix are used for rural and suburban residential zones. The criteria provide for residential densities that are between the large lot, rural ranch development and the small lot, urban, residential development.

Development
Designator
Lot Size1 Units Per Lot2 Building Height3 Perimeter Yard4
A 36 acres 1 30’ CC
B 180,000 1 30’ CC
C 144,000 1 30’ BB
D 36,000 1 30’ BB
E 36,000 2 30’ BB
F 36,000 1 25’ BB

1Minimum lot size listed in square feet unless otherwise stated.
2Density. For calculation, refer to Sec. 3.2.10.
3Maximum. For measurement and exceptions, refer to Sec. 3.2.7.
4For applicability, refer to Sec. 3.2.6.

B. Low-Density Matrix. Development criteria in this matrix are used for low-density urban zones. The criteria are primarily for the single parcel, detached, single-family dwelling.

Development
Designator
Lot Size1 Lot Coverage2 Units Per Lot3 Building Height4 Perimeter Yard5
G 7,000 70% 1 25’ AA
H 10,000 70% 2 25’ AA
I 5,000 70% 1 25’ AA

1Minimum lot size listed in square feet.
2Maximum. For calculation, refer to Sec. 3.2.9.
3Density. For calculation, refer to Sec. 3.2.10.
4Maximum. For measurement and exceptions, refer to Sec. 3.2.7.
5For applicability, refer to Sec. 3.2.6.

C. Medium-Density Matrix. Development criteria in this matrix provide for single parcel, single-family, attached or detached dwellings and establish lower density ranges for multiple-family structures.

Development
Designator
Site Area1 Lot Coverage2 Density3 Building Height4 Perimeter Yard5
J 2,500 90% 17 40’ DD
K 5,000 75% 15 25’ BB
L 5,000 75% 22 25’ BB
M 7,000 70% 8 16’ BB
N 5,000 70% 8 25’ BB

1Minimum site area listed in square feet.
2Maximum. For calculation, refer to Sec. 3.2.9.
3For calculation, refer to Sec. 3.2.10.
4Maximum. For measurement and exceptions, refer to Sec. 3.2.7.
5For applicability, refer to Sec. 3.2.6.

(Ord. No. 9780, §4, 10/14/02)

D. High-Density Matrix. The development criteria included in this matrix provide for development of high- density, multiple-family structures.

Development
Designator
Lot Coverage1 Density2 Building Height3 Perimeter Yard4
O 75% 36 25’ CC
P 70% 36 40’ CC
R 70% 44 40’ CC
S 80% 87 75’ CC
T
(Reserved)
       
U
(Reserved)
       
V
(Reserved)
       

1Maximum. For calculation, refer to Sec. 3.2.9.
2Density. For calculation, refer to Sec. 3.2.10.
3Maximum. For measurement and exceptions, refer to Sec. 3.2.7.
4For applicability, refer to Sec. 3.2.6.

E. High-Rise Density Matrix. The development criteria included in this matrix provide for multiple-family structures in zones allowing for the development of high-rise buildings.

Development
Designator
Lot Area FAR1 Lot Coverage2 Building Height3 Perimeter Yard4
W None 6 80% 140’ DD
X None 10.5 80% 300’ DD
Y
(Reserved)
         
Z
(Reserved)
         

1Maximum floor area ratio (FAR). For calculation, refer to Sec. 3.2.11.
2Maximum. Refer to Sec. 3.2.9.
3Maximum. For measurement and exceptions, refer to Sec. 3.2.7.
4For applicability, refer to Sec. 3.2.6.

F. Flexible Lot Development (FLD) Density Matrix. The following regulations apply to FLD projects. Development Alternative A is for standard FLD projects pursuant to Section 3.6.1.2.B.1 (Standard FLD). Development Alternative B is for FLD projects developed using a maximum density option pursuant to Section 3.6.1.2.B.2 (Maximum Density Option). (Ord. No. 10636, §2, 2/24/09)

FLD
Designator
Zone Development
Alternative
Site Coverage
(Maximum Percentage Allowable)
Allowable Density Building Height Perimeter Yard*
FLD-1 SR A 8 0.25 30’ BB
FLD-2 RX-1 A 33 1.00 30’ BB
FLD-3 RX-2 & SH A 33 2.25 25’ BB
FLD-4 R-1 & MH-1 A
B
50
70
5.14
6.25
25’
25’
BB
BB
FLD-5 MH-2 A
B
62
75
8.00
15.00
25’
25’
BB
BB
FLD-6 R-2 A
B
62
75
8.71
22.00
25’
25’
BB
BB
FLD-7 R-3 A
B
70
75
36.00
44.00
40’
40’
CC
CC
FLD-8 O-1, O-2, & O-3 A 75 22.00 25’ BB
FLD-9 C-1 A 75 36.00 25’ CC
FLD-10 C-2 & C-3 A 75 44.00 40’ CC

(Ord. No. 10636, §3, 2/24/09)

3.2.3.2 Nonresidential Development Designator. The development criteria included in these matrices are applied as required in the specific zone primarily for nonresidential uses.

A. Located in Residential Zones. The development criteria included in this matrix are primarily for application on nonresidential uses when permitted in residential zones. These Designators are also applied to a limited number of uses in nonresidential zones.

Development
Designator
Site Area1 FAR2 Lot Coverage3 Building Height4 Perimeter Yard5
1 30 acres 0.03 10% 25’ FF
2 10 acres 0.06 10% 30’ FF
3 10 acres 0.10 15% 25’ FF
4 4,000 0.03 10% 12’ FF
5 144,000 0.10 15% 30’ FF
6 144,000 0.30 50% 25’ FF
7 72,000 --- 60% 25’ FF
8 43,560 0.15 20% 25’ FF
9 36,000 0.10 15% 30’ EE
10 36,000 0.30 50% 25’ EE
11 20,000 0.10 15% 25’ CC
12 20,000 0.40 60% 25’ CC
13 16,000 0.10 15% 25’ DD
14 16,000 0.35 50% 25’ DD
15 14,000 --- 80% 25’ BB
16 10,000 --- 80% 25’ BB
17 7,000 0.50 70% 25’ BB
18 0 0.50 70% 40’ CC
19 1.5 acres 0.50 70% 25’ CC
20 2.5 acres --- 60% 25’ BB
21 36 acres 0.03 10% 30’ FF
22
(Reserved)
         
23
(Reserved)
         
24
(Reserved)
         
25 180,000 0.10 20% 30’ FF

1Minimum site area in square feet unless otherwise stated.
2Maximum floor area ratio (FAR). For calculation, refer to Sec. 3.2.11.
3Maximum. Refer to Sec. 3.2.9.
4Maximum. For measurement and exceptions, refer to Sec. 3.2.7.
5For applicability, refer to Sec. 3.2.6.

(Ord. No. 9102, §2, 8/3/98)

B. Located in Nonresidential Zones. The development criteria included in this matrix are primarily for application on nonresidential uses when permitted in nonresidential zones.

A. Located in Residential Zones. The development criteria included in this matrix are primarily for application on nonresidential uses when permitted in residential zones. These Designators are also applied to a limited number of uses in nonresidential zones.

Development
Designator
Site Area1 FAR2 Building Height3 Perimeter Yard4
26 10,000 0.25 16’ BB
27 0 0.50 26’ BB
28 0   30’ DD
29 0   30’ DD
30 0   40’ DD
31 0   40’ DD
32 1,500   30’5 DD
33 0   50’ DD
34 0   75’ DD
35 0   140’ EE
36 0   300’ EE
37
(Reserved)
       
38 0   16’ BB
39
(Reserved)
       
40 5,000 0.90 16’ AA
41 5,000 0.50 25’ BB

1Minimum site area in square feet unless otherwise stated.
2Maximum floor area ratio (FAR). For calculation, refer to Sec. 3.2.11.
3Maximum. For measurement and exceptions, refer to Sec. 3.2.7.
4For applicability, refer to Sec. 3.2.6.
5Unless a greater height is permitted by the Sign Code.

(Ord. No. 8610, §1, 11/27/95)

3.2.4 SECONDARY LAND USE. Land use activities that are allowed as Secondary Land Uses to a principal use are subject to the provisions described below.

3.2.4.1 Development Criteria. Any land use permitted as a secondary use shall be developed within the requirements of the Development Designator of the Principal Land Use, but all other development requirements of Article III are based on the specific Secondary Land Use.

3.2.4.2 Review. All proposed applications for Secondary Land Uses shall be submitted for zoning compliance review and approval. Compliance with requirements for a Secondary Land Use and with requirements of the zone are required for approval. (Ord. No. 9392, §1, 5/22/00)

3.2.5 ACCESSORY USES AND STRUCTURES. Those land uses and structures associated with, and incidental to, a principal structure are accessory and subject to the provisions described below.

3.2.5.1 Accessory Uses. An accessory use must comply with the following.

A. The use is incidental to the principal use and is located on the same parcel as the principal use;

B. The use is intended for the occupants, residents, customers, employees, or guests of the principal use; and

C. The use does not substantially alter the exterior appearance or character of the principal use or structure to which it is incidental.

D. Animals may be kept for personal use in all zones subject to Tucson Code, Chapter 4, and any applicable health regulations. (Ord. No. 8808, §1, 1/27/97)

3.2.5.2 Accessory Structures. In all zones, the structures used for accessory uses shall comply with the following.

A. An accessory structure can be built only on a lot occupied by a principal structure or use.

B. An accessory building shall be developed in conformance with the requirements of the Development Designator of the Principal Land Use, but all other development requirements of Article III are based on the specific Accessory Land Use. (Ord. No. 8582, §1, 9/25/95)

C. An accessory structure, which exceeds the allowable height of a wall within a perimeter yard and is detached from a principal structure, shall comply with the perimeter yard width requirements of the principal structure, except that the accessory structure may be built to a parcel line with the consent of the adjoining or, when separated by an alley, adjacent property owner(s). Accessory structures, such as light poles, flagpoles, and other tall and narrow structures that are similar, are exempt from the setback requirement. (Ord. No. 9374, §1, 4/10/00)

D. An accessory structure, except for a stable or enclosure for animals, may be attached to a principal structure, provided that its construction complies with the development requirements of the principal structure.

E. The use of solar energy collectors for the purpose of providing energy for heating or cooling is permitted in all zones, whether as part of a principal structure or as an accessory structure. Such solar collection devices shall not be included in computing lot coverage. (Ord. No. 9179, §1, 12/14/98)

F. This Section is not intended to apply to buildings of five (5) feet or less in height and ten (10) square feet or less in area, such as doghouses or refuse container enclosures, nor to play equipment.

G. All structures for animals must be set back at least fifty (50) feet from all property lines, except corrals which must be set back ten (10) feet from all property lines.

H. The maximum height of a wall or fence within a perimeter yard is six (6) feet; however, the wall or fence may be higher than six (6) feet, but no higher than ten (10) feet, if: (See Illustration 3.2.5.2.H.)

1. At least seventy-five (75) percent of the area above six (6) feet in height is left unobstructed and open through the use of architectural elements, such as arches, columns, or wrought iron, or

2. Part of, or located on top of, a retaining wall no higher than ten (10) feet measured from design grade and no higher than six (6) feet measured from the top of the retaining portion of the wall, or

3. A greater height is required through the rezoning process or the Special Exception Land Use process, or

4. A greater height is required by a specific regulation in the LUC.

(Ord. No. 8582, §1, 9/25/95; Ord. No. 9293, §1, 9/27/99)

I. In nonresidential zones, walls or fences, as permitted in H. above, may exceed the height requirements, provided the wall or fence complies with perimeter yard requirements applicable to buildings on the site. (Ord. No. 8582, §1, 9/25/95)

3.2.5.3 Specifically Within Residential Zones. The structures used for an accessory use within a residential zone shall comply with the following.

A. An accessory structure shall not be a dwelling unit but may be a building that is used as sleeping quarters by the residents of the dwelling unit in accordance with Sec. 3.2.5.1.A and .B. The sleeping quarters may include bedrooms, bathrooms, and a sitting room, provided the structure complies with Sec. 3.2.5.1.C and is not the dominant use of the property. (Ord. No. 8808, §1, 1/27/97)

B. Accessory structures shall not exceed twelve (12) feet in height, unless attached to a principal structure. If attached to the principal structure, maximum height permitted is the same as for the principal structure.

C. Detached accessory structures are not allowed in the buildable area extending the full width of the lot between the principal structure and the front street lot line, except for terraces and steps not over three (3) feet high above the natural grade, paved areas, and fences or walls.

(Ord. No. 8582, §1, 9/25/95)

3.2.5.4 Specifically Within Nonresidential Zones. The structure used for an accessory use within a nonresidential zone shall comply with the following.

A. An accessory structure shall not be occupied as a dwelling, except as a caretaker's facility.

B. Accessory structures shall not exceed the height limitation of the principal structure.

C. The area of a site occupied by an accessory use or structure shall be included as part of the lot coverage calculation.

3.2.6 PERIMETER YARDS.

3.2.6.1 Purpose. This Section establishes use separation criteria based on the need for open space, solar access, and privacy and on minimizing negative visual impacts between developments.

3.2.6.2 Application. A perimeter yard shall be provided along all lot lines. The minimum width of the perimeter yard required for each development is based on the zoning classification of the adjacent parcel(s) along each individual lot line and is listed in Sec. 3.2.6.4.

3.2.6.3 Measurement. The width of the perimeter yard is the distance measured horizontally from a specified point to the face of each exterior building wall at the wall's highest point. The specified point is the property line when it is an interior property line. Along a street property line, the specified point is described in Sec. 3.2.6.5. (See Illustration 3.2.6.3.)

A vertical structural member(s) (i.e., post, column, dormer wall) supporting a roof extension from the principal structure is considered a wall for applying perimeter yard requirements.

The perimeter yard may have different widths at various points along the same property line, because the perimeter yard width is measured to the face of each vertical exterior surface of the building.

On cul-de-sac and eyebrow front lots, the minimum street perimeter yard depth may be measured from a straight line drawn between the front lot corners, rather than measured directly from the curved front property line, except as provided in Sec. 3.2.6.5.B.2. In no case, however, shall the minimum street perimeter yard be reduced in excess of fifty (50) percent by this alternative measurement.

Where an unbroken section of a wall or a building is not parallel with the lot line, the required perimeter yard may be applied to the average width; however, such perimeter yard shall not be narrower at any point than half the required width, nor narrower at any point than three (3) feet.

3.2.6.4 Perimeter Yard Width Matrix. The following matrix provides for perimeter yard widths that are applicable with the Development Designator provisions of Sec. 3.2.3.1 and Sec. 3.2.3.2.A and .B. When using the Development Designator provisions of Sec. 3.2.3.1.F, Residential Cluster Project Density Matrix, these perimeter yards apply only to the site boundaries. (See Illustration 3.2.6.4.)

Perimeter Yard Width Requirement Based on Adjacent Zoning Classification or Street Frontage
Perimeter Yard Indicator OS-SR SH-RX-2 MH-1, MH-2, R-1, and R-2 MU, PAD, and R-3 All Office and Commercial Zones, OCR-1, and OCR-2 All Industrial Zones Street Frontage
AA 25’ 20’ 6’ or 2/3(H)* (H) (H) (H) Sec. 3.2.6.5
BB 25’ 20’ 10’ or 3/4(H)* 10’ or 3/4(H)* (H) (H) Sec. 3.2.6.5
CC 25’ 20’ or (H) 10’ or 3/4(H)* 10’ or 3/4(H)* (H) (H) Sec. 3.2.6.5
DD 25’ 20’ 1 1/2(H) 1 1/2(H) 0 0 Sec. 3.2.6.5
EE 25’ 20’ 2(H) 2(H) 0 0 Sec. 3.2.6.5
FF 4(H) 4(H) 2(H) 1 1/2(H) 0 0 Sec. 3.2.6.5
GG 20(H) 20(H) 20(H) 20(H) 15(H) 15(H) 20(H)

* The greater of the two dimensions prevails.
(H) = Height of proposed exterior building wall.
2/3(H) is read: Two-thirds the height of the proposed exterior building wall.

(Ord. No. 8582, §1, 9/25/95; Ord. No. 9374, §1, 4/10/00)

3.2.6.5 Street Perimeter Yard. The street perimeter yard width is determined as provided below, unless a specific distance is noted in Sec. 3.2.6.4, Perimeter Yard Width Matrix, or unless special zoning requirements dictate a greater distance or different point of measurement.

A. Within established areas, the front street perimeter yard is twenty (20) feet or one and one-half (1 1/2) the height of the proposed wall (H), measured from the street property line, whichever is greater, up to a maximum of ninety (90) feet. Where a lot abuts more than one (1) street, the owner shall choose which street lot line is the front lot line. From other than the front lot line, the street perimeter yard is ten (10) feet.

B. Within developing areas, the minimum required building setback is determined by the type of building proposed and the projected average daily traffic (ADT) of the street. Where setback regulations for developing areas apply, a minimum setback shall be provided between a building and a street as follows.

1. All Buildings Except Carports and Garages in Single-Family and Duplex Development. A minimum setback shall be provided between a building and an adjacent street as determined in Table 3.2.6-I, except setbacks for carports and garages in single-family and duplex development, which are determined in Sec. 3.2.6.5.B.2. The setback is based on the projected street ADT. Of the two (2) or more setback distances listed in Table 3.2.6-I for each ADT range, the building setback which provides the greatest distance from the street shall be provided. (See Illustration 3.2.6.5.B.1.)

TABLE 3.2.6-I
BUILDING SETBACK BY STREET ADT1
ADT of 140 or less ADT over 140 but less than 1,000 ADT of 1,000 or greater
5 feet2
or
1/2 H2
or
1 foot3
21 feet4
or
H4
21 feet2
or
H2

Where:
H - The height of the proposed exterior building wall.
1In all circumstances, the greater setback resulting from the alternate measurement is required.
2The setback is measured from the back of existing curb or future curb location.
3The setback is measured from the property line or from the nearest edge of the sidewalk or future sidewalk location.
4The setback is measured from the outside edge of the nearest adjacent travel lane.

2. Carports and Garages in Single-Family and Duplex Development. For carports, garages, or similar parking structures in single-family or duplex residential development on individual lots, a minimum setback shall be provided using either of the following alternatives. (See Illustration 3.2.6.5.B.2.)

a. A minimum setback of nineteen (19) feet from the back of sidewalk to allow sufficient space for a motor vehicle to be parked in front of the carport or garage, measured as follows.

1. Eighteen (18) feet (the length of a standard parking space) must be provided in front of the carport or garage and measured so that the full eighteen (18) foot parking space is available for parking on-site.

2. The eighteen (18) foot parking space shall be no closer than one (1) foot from back of sidewalk of the street from which access is gained.

b. A minimum setback of one (1) foot from the back of sidewalk of the street from which access is gained, if all of the following apply.

1. The street from which access is provided has a projected ADT of one hundred forty (140) vehicle trips or less.

2. The setback is measured so that the parking structure and the parking space within that structure are located completely on-site and do not encroach into the one (1) foot setback.

3. The distance between the street pavement edge and the parking structure is eight (8) feet or less. The purpose of this requirement is to discourage motor vehicle tandem parking that would block the pedestrian area or overhang onto the roadway.

3. When the setback is measured from the nearest edge of sidewalk, back of sidewalk, or future sidewalk, and there is no existing or proposed sidewalk, the nearest edge of the pedestrian and utility area adjacent to the street's roadway is used as the point of measurement for the setback. The location and width requirements for pedestrian and utility areas are found in Development Standard No. 3-01.0, Street Development Standard.

4. Developing area setbacks shall not be less than the minimum width of the landscaping requirements of Sec. 3.7.2.4.

3.2.6.6 Exceptions to Perimeter Yards. Encroachment into the required perimeter yard is allowed as provided below.

A. Along interior property lines, the following may extend two (2) feet into the required width, provided the yard is not reduced to less than three (3) feet.

1. Chimney.

2. Roof overhang.

3. Bay windows.

B. Along street property lines, as provided below.

1. Within established areas, the following may extend two (2) feet into the required perimeter yard.

a. Chimney.

b. Roof overhang.

c. Stairs.

d. Bay windows.

e. Open structures.

2. On any corner lot, no fence, structure, object, or planting shall be erected or maintained so as to interfere with the sight visibility triangle provisions of Development Standard 3-01.0.

C. Structures within perimeter yards.

1. Architectural features which are part of a solar energy system may project up to four (4) feet into required front perimeter yards. Such architectural features include, but are not limited to, overhangs, moveable insulating walls and roofs, detached solar collectors, reflectors, and piping.

2. A wall or fence not over six (6) feet high may be erected within the limits of a perimeter yard.

3.2.7 STRUCTURE HEIGHT MEASUREMENT.

3.2.7.1 Purpose. The purpose of this Section is to establish a uniform and consistent method for measuring structure heights, which allows for changes in topography and for architectural diversity.

3.2.7.2 Measurement.

A. Buildings. The vertical distance of a building is measured from design grade elevation, at any individual point within the building footprint, to the highest point of a flat roof; to the deck line of a mansard roof; or to the middle (between the eave and ridge) of the highest gable of a pitched or hipped roof, except as follows. (See Illustration 3.2.7.2.)

1. Historic Preservation Zone (HPZ). Building height is the vertical distance measured between the highest part of a structure and the finished grade at the midpoint of the front facade of the principal structure, excluding chimneys, mechanical equipment, and other miscellaneous additions.

2. Airport Environs Zone (AEZ). Measurement of height for buildings as provided in Sec. 3.2.7shall apply, except where the height may exceed the maximum height requirements of Sec. 2.8.5.7, Airport Hazard Districts, in which case Sec. 2.8.5.7prevails.

3. Scenic Corridor Zone (SCZ). The vertical distance of a building is measured from design grade, at all points within the building footprint, to the highest point on a roof. Any wall extending above the roof, such as a parapet wall or a fire wall, shall be considered part of the roof for purposes of measuring height.

4. Hillside Development Zone (HDZ). See height measurement requirements in Sec. 2.8.1.8.A. (Ord. No.  9138, §1, 10/5/98)

(Ord. No. 9781, §2, 10/28/02)

B. All Other Structures. The vertical distance of all structures, other than buildings, will be measured from design grade at the base of the structure at all points along that structure to the top of the structure. For structures within six (6) feet of a property line, the design grade used for measuring height is the lower of the two (2) grades on each side of that property line.

1. Airport Environs Zone (AEZ). Measurement of height for structures and trees as provided in Sec. 3.2.7 shal apply, except where the height may exceed the maximum height requirements of Sec. 2.8.5.7 , Airport Hazard Districts, in which case Sec. 2.8.5.7 prevails.

3.2.7.3 Exceptions. The following structural elements may extend above the maximum allowed height, subject to any limitations listed. (See Illustration 3.2.7.3.)

A. Ornamental elements of the buildings and structures, such as spires, cupolas, belfries, clock towers, and domes, provided that such elements:

1. Are not for human occupancy, and

2. Do not exceed ten (10) feet above the allowed structure height, except as follows:

3. Ornamental elements of buildings and structures proposed to exceed ten (10) feet above the allowed structure height are subject to review by the Design Review Board in accordance with Sec. 5.1.8

a. The ornamental element is an integral part of the building’s architecture, not for human occupancy.

b. Ornamental elements proposed to exceed ten feet (10 ft.) above the allowed structure height may not be used for commercial advertising.

c. The applicant must demonstrate how the proposal minimizes impacts to existing land uses by including a viewshed analysis and an analysis of the project site grades and adjacent property grades as part of their submittal.

d. Setbacks required for the architectural element will be one foot (1 ft.) for each additional foot in height by which it exceeds the base allowance of ten feet (10 ft.).

(Ord. No. 10166, §1, 6/21/05)

B. Chimneys, mechanical penthouses, and bulkheads for stairwells, elevator shafts, or skylights, provided that such elements:

1. Are not for human occupancy,

2. Do not exceed ten (10) feet above the allowed structure height, and

3. Do not exceed twenty-five (25) percent of the total roof area of the building on which they are located.

C. Mechanical equipment, except solar energy equipment, and accessories necessary to the operation or  maintenance of the building, provided that such elements:

1. Do not exceed six (6) feet above the allowed structure height,

2. Do not exceed twenty-five (25) percent of the total roof area of the building on which they are located,

3. Are concealed by an opaque screen, and

4. Are located away from the edge of the building a distance equivalent to the height of the elements.

D. Solar energy equipment, provided that such elements do not exceed the allowable height limits by more than ten (10) feet.

E. Parapet walls and safety railings, provided they do not exceed the allowable height by more than four (4) feet.

F. Communications antennae not in conjunction with a communications facility, excluding dish antennae greater than three (3) feet in diameter, provided such elements do not exceed the allowable height limits by more than five (5) feet.

G. Dish antennae, greater than three (3) feet in diameter, provided that such elements:

1. Do not exceed the allowable height limits by more than ten (10) feet;

2. Are located as close to the center of the roof structure as possible;

3. Are screened from view, to the maximum extent possible without interfering with reception, from the street frontage of the property at pedestrian level by an opaque screen, such as a parapet wall at the roof's edge; and

4. Are located on a building with a structure height greater than forty (40) feet.

H. Communications antennae, other than those associated with wireless communications, in conjunction with a communications facility do not have a maximum height limitation, provided the antennae are located at least one (1) foot distance for every foot in height measured from all property lines of residentially zoned property. (Ord. No. 8813, §1, 3/3/97)

I. If the Mayor and Council authorize a change in the zoning classification of a property and buildings exist on the property which exceed the maximum required height for the proposed land use, the existing buildings  shall be considered conforming. This exception applies only to buildings existing at the time of authorization, except as provided by Sec. 3.2.7.3 .J. (Ord. No. 8704, §1, 5/13/96)

J. New construction in a Historic Preservation Zone (HPZ) may exceed the height requirements of the zone if additional height is needed to be compatible with the height of other buildings within the development zone as determined by the Development Services Department Director. (Ord. No. 8704, §1, 5/13/96; Ord. No.  9967, §3, 7/1/04)

3.2.8 ACCESS PROVISIONS.

3.2.8.1 Purpose. This Section is established to: assure that all parcels have legal and physical access to a public street; require reasonable improvements for pedestrian facilities; increase public safety by lessening the conflict between vehicular and pedestrian activities; aid in improving air quality in the City of Tucson by providing for one (1) pedestrian mode of alternate travel; and provide design standards for pedestrian circulation paths.

3.2.8.2 Acceptable Types of Access.

A. Public street access, which is ingress-egress to a parcel provided by an abutting public street.

B. Private street access, which is ingress-egress to a parcel provided by an abutting private street in which the owner of the parcel has a legal interest to assure perpetual use for access.

C. Access easement, which is ingress-egress to a parcel provided over some other parcel through an area dedicated for such perpetual use.

3.2.8.3 Width of Access.

A. The minimum width required for access to a parcel is that dimension sufficient to provide for the type of access, per Sec. 3.2.8.2. The minimum required width is based on access improvements being centered within the dimension. If the improvements are located off-center, an additional width may be required.

B. All lots shall be designed with access to a public street. If a proposed lot does not have public street frontage, access must be provided by means of a private street or an access easement of sufficient size to accommodate motor vehicle and pedestrian access and public services as required for the type of development proposed for the lot.

I. access is provided by an easement and the easement serves more than three (3) single-family homes or duplexes, the City may require the easement to be developed as a street or as a parking area access lane (PAAL). The determination as to whether a developed street or PAAL is required will be made at the time of review of the proposed land division based on the need for public services, such as utilities, refuse collection, and fire suppression, and on the projected average daily traffic (ADT) of the access easement.

3.2.8.4 Pedestrian Facilities. All land uses subject to the applicability of this Section shall provide pedestrian facilities.  Pedestrian facilities, for the purpose of this Section, are sidewalks in conformance with the standards indicated below. (Ord. No. 9138, §1, 10/5/98)

A. Pedestrian facilities located in a street, either public or private, shall be designed in compliance with  Development Standard 3-01.0. (See Illustration 3.2.8.4 .A.)

B. Pedestrian facilities located in areas other than streets shall be designed in compliance with Development  Standard 2-08.0. (See Illustration 3.2.8.4.B.)

C. Pedestrian facilities designated for the physically disabled shall be designed in compliance with the  Uniform Building Code.

D. Applicability. The provisions apply to the following.

1. All new uses of land or structures.

2. All existing uses of land or structures legally existing as of September 24, 1990, which are expanded in lot coverage, floor area, number of parking spaces, or seating capacity, as follows.

a. If the expansion is less than twenty-five (25) percent, these provisions apply only to the proposed expansion. The remainder of the use or structure is governed by the provision in force at the time of initial approval for the use or structure.

b. If the expansion is twenty-five (25) percent or more, these provisions apply to the existing use or structure, as well as the expansion.

c. All expansions which occur after the adoption of this ordinance are cumulated in determining the twenty-five (25) percent expansion. After the use of the land or structure is brought into conformance with the provisions of this Section, additional changes to the existing use of the land or structure will commence cumulating over time as of the date the existing use of the land or structure is brought into conformance.

d. Nothing contained in Sec. 3.2.8.4

3.2.8.5 Exceptions.

A. Access to individual parcels may be provided by a common access between two (2) or more parcels, provided it is established as commonly owned property or by a use easement to assure access.

3.2.9 LOT COVERAGE.

3.2.9.1 Purpose. This Section provides a uniform and consistent method of determining and applying the lot coverage requirements of individual land uses.

3.2.9.2 Application. Lot coverage includes the following. (See Illustration 3.2.9.2.)

A. Any area of a building within the outside edges of the exterior walls at ground level (design grade). Any raised extensions of the ground floor, such as bay windows and stairs that are less than six (6) feet above the ground, are considered part of the building's lot coverage.

B. Vehicular use areas, measured within the outside edges of any area allocated to vehicle use, whether improved or unimproved. To determine the size of an unimproved vehicular use area, the minimum dimensions for parking spaces, access lanes, and pedestrian facilities, as required by the appropriate Development Standard, are used to determine lot coverage.

C. Storage areas, measured from outside edge to outside edge of any area allocated to storage use. Storage areas include enclosed or open areas used for storage or display of materials, equipment, refuse, or vehicles.

3.2.9.3 Exceptions. The following are excluded from the lot coverage calculation to encourage design flexibility and provide for additional amenities.

A. Buildings. Building lot coverage does not include the following areas, provided the areas are located on the ground floor.

1. Roofed areas, open on at least one (1) side, which provide shelter to exterior areas, such as balconies, entrances, stoops, and terraces, provided they are not used for utilities, maintenance, laundry, storage, or motor vehicle parking.

2. Any part of a building used for recreational purposes provided the recreation area:

a. Is separated by a wall from nonrecreational areas such as laundry rooms,

b. Is designated for common use by tenants,

c. Is not used by the general public, and

d. Is not within a dwelling unit.

3. Any outdoor area over an underground building which is either landscaped, used for recreation purposes, or both. The roof of the building can be a maximum of three (3) feet above design grade measured to its highest point.

4. Roofed interior space which provides a physical connection to the outdoors and natural lighting, either directly or indirectly. In addition, the space:

a. Shall not, in whole or in part, be designated as tenant area;

b. Shall not have more than fifteen (15) percent of the total area allocated toward corridor space;

c. Shall be at least thirty (30) feet wide in any horizontal direction;

d. Shall have a minimum floor-to-ceiling height of twenty (20) feet; and

e. Shall not be within a dwelling unit.

5. Solar Collectors. Solar collectors, whether part of the principal structure or an accessory structure, are not included in lot coverage calculations.

B. Vehicular Use Areas. Within a vehicular use area, any landscaped area greater than twenty-five (25) square feet is excluded, provided the landscaped area is:

1. Larger than three (3) feet in width, and

2. Is curbed to protect it from vehicular traffic.

3.2.9.4 Lot Coverage Calculation. The amount of lot coverage per site is not to exceed the lot coverage percentage listed for the proposed land use within the zoning classification of the site.

The lot coverage percentage is determined by the total amount of land area that would fall under the lot coverage definition, divided by the total land area of the site.

3.2.10 RESIDENTIAL DENSITY CALCULATIONS.

3.2.10.1 Purpose. This Section provides uniform methods for determining residential densities on individual sites.

3.2.10.2 Applicability. Residential density for all residential projects is calculated as follows.

A. Residential density in residential projects developed under Development Designators "A" through "I", as listed in Sec. 3.2.3.1.A and Sec. 3.2.3.1.B, is based on one (1) dwelling unit per minimum size parcel by area, exclusive of any street and drainageway dedications or exclusive use easements. Because the acreage of a parcel used for street and drainageway purposes differs for each development project, it is difficult to provide a simple calculation that would give an exact density figure.

The following provide two (2) methods of calculating approximate density for a project. The number of units obtained through these calculations is an estimate and can only be verified by the actual design of the project. Should there be a need to express a density ratio per acre for these Development Designators, for comparison purposes only, such ratio will be calculated using the second method assuming thirty (30) percent of the site would be used for streets, drainageways, or other uses whose acreage is not included to calculate allowable density.

1. The first method of calculation gives the highest possible density that can be achieved on a parcel.  However, to achieve this density, the following two (2) design criteria must be present. (See  Illustration 3.2.10.2. Method 1.)

a. The property can be developed without additional dedications for streets, drainageways, or exclusive use easements.

b. Each lot is the minimum size permitted by the assigned Development Designator.

The calculation is simple. The site area, expressed in square feet, is divided by the minimum lot size permitted by the assigned Development Designator.

2. The second method assumes that the project design requires dedication of either streets, drainageways, or exclusive use easements or will have other site conditions that do not allow every square foot of the property to be included in an individual lot. Also, due to varying widths of street and drainageway rights-of-way and lot configurations, it is impossible to project an exact number of units or lots that can be achieved. Since the amount of site area used for streets, drainageways, etc., varies from project to project, it is necessary to approximate the amount of site area by percentage that will be needed for those purposes. It will be assumed, to illustrate the calculations, that thirty (30) percent of the site area will be utilized for such purposes. (See Illustration 3.2.10.2. Method 2.)

The calculation is the site area, expressed in square feet, minus thirty (30) percent of the site area, divided by the minimum lot size permitted by the assigned Development Designator.

B. Residential density in residential projects developed under Development Designators "J" through "U", as listed in Sec. 3.2.3.1.C and Sec. 3.2.3.1.D, is calculated in the following manner.

1. Multiply the area of the site, in acreage, by the density (units per acre ratio) listed for the assigned  Development Designator.

Example:

Development Designator "K"
Units Per Acre Ratio: 15.0
Project Site Area: 6 acres

Calculation:

Units per acre x site area = no. of units
15 x 6 = 90 units

2. Exception. Any site area dedicated or sold at nominal cost to the City for public purposes is included as part of the site area for calculation of density, provided:

a. The additional density is less than ten (10) percent of the density permissible for the rest of the site area;

b. Such dedication was not a condition of approval for applications, such as, but not limited to, rezonings or variance requests;

c. Such dedication does not include right-of-way dedicated as part of a subdivision plat; and

d. A legally binding agreement to dedicate or sell at nominal cost to the City is submitted as part of the application.

C. Residential density for residential projects developed under Development Designators "W" through "Z", as listed in Sec. 3.2.3.1.E, is based on a Floor Area Ratio (FAR), in accordance with Sec. 3.2.11.2.B.

D. Residential density in residential projects developed under Development Designators "FLD-1" through "FLD-10", as listed in Sec. 3.2.3.1.F, is based on the developable area of the site (refer to Sec. 6.2.4. for definition of developable area). (Ord. No. 9138, §1, 10/5/98, Ord. No. 10636, §12, 2/24/09)

3.2.11 FLOOR AREA RATIO (FAR) CALCULATION.

3.2.11.1 Purpose. This Section provides a uniform method for calculating the maximum amount of floor area that may be achieved on a site, when the floor area is based on a ratio. The ratio, or Floor Area Ratio (FAR), is defined in Sec. 6.2.6. FARs are used in conjunction with lot coverage, perimeter yard requirements, and height limitations to determine and define the building bulk that may occur on a given site.

Floor Area (FA), as defined, does not include any interior motor vehicle parking or off-street loading that is accessory to the principal use.

3.2.11.2 Applicability. FARs are applicable when listed as part of the development criteria of a Development Designator.

Land use intensity for all nonresidential uses and residential density for high-rise residential uses are calculated using FARs. The calculations are as follows.

A. General Rule of Application. In general, the FAR assigned to each Development Designator is based on the most favorable situation, so the maximum FA will not be achieved on all projects. To achieve the maximum possible FA permitted by the FAR, the other development criteria (perimeter yard requirement, lot  coverage, motor vehicle parking, etc.) would have to be at their least restrictive levels.

Example:

A commercial development adjacent to a residential zone would have perimeter yard requirements which would prohibit maximizing the permitted FA. The same commercial development located adjacent to a commercial zone or another nonresidential zone would not have perimeter yard requirements and would have a greater opportunity to achieve the maximum permitted FA.

B. Residential Projects. Residential density calculations for residential projects developed under Development Designators "W" through "Z", as listed in Sec. 3.2.3.1.E, are based on a FAR. The FAR provides the maximum amount of FA that can be developed on a site. The FA can be divided into any number of units or accessory buildings, provided the combined square footage of all units and accessory buildings does not exceed the permitted FA of the site. (See Illustration 3.2.11. Example 1.)

1. Standard Calculation. To obtain the amount of FA permitted on a site, the area of the site, expressed in square feet, is multiplied by the FAR listed for the assigned Development Designator. The result is the maximum amount of FA permitted on the site. The FA permitted on a site may be divided into any number of dwelling units and accessory buildings.

The resulting FA includes all floor area, except interior motor vehicle parking and loading areas. To obtain an approximate number of units that could be developed, all areas not specifically allocated to a dwelling unit, such as interior corridors, lobbies, and janitorial areas, must be deducted from the total FA. The remaining FA could then be divided by the average size unit to obtain the approximate  number of dwelling units for the site. For example, if thirty (30) percent of the FA is for non-dwelling uses and seventy (70) percent for dwelling units, then multiply the FA by 0.70. Divide that amount by the average size unit. The result is the approximate number of units.

2. Exception. Any site area dedicated or sold at nominal cost to the City for public purposes is included as part of the site area for calculation of density, provided:

a. The additional density is less than ten (10) percent of the density permissible for the rest of the site area;

b. Such dedication was not a condition of approval for applications, such as, but not limited to, rezonings or variance requests;

c. Such dedication does not include right-of-way dedicated as part of a subdivision plat; and

d. A legally binding agreement to dedicate or sell at nominal cost to the City is submitted as part of the application.

C. Nonresidential Projects. All nonresidential Development Designators include FARs as an integral part of their development criteria. The FAR provides the maximum amount of FA that can be developed on the site. The FA permitted on a site may be allocated to principal or accessory buildings. (See Illustration 3.2.11. Example 2.)

1. Standard Calculation. To obtain the amount of FA permitted on the site, the area of the site, expressed in square feet, is multiplied by the FAR listed for the assigned Development Designator. The resulting permitted FA may be divided into any number of principal and accessory buildings.

2. Exception. Any site area dedicated or sold at nominal cost to the City for public purposes is included as part of the site area for calculation of density, provided:

a. The additional density is less than ten (10) percent of the density permissible for the rest of the site area;

b. Such dedication was not a condition of approval for applications, such as, but not limited to, rezonings or variance requests;

c. Such dedication does not include right-of-way dedicated as part of a subdivision plat; and

d. A deed for the area or a legally binding agreement to dedicate or sell at nominal cost to the City is submitted as part of the application.

3.2.12 SOLAR CONSIDERATIONS.

3.2.12.1 The use of solar energy collectors for the purpose of providing energy for heating or cooling is permitted in all zones, whether as part of a principal structure or as an accessory structure. (Ord. No. 9179, §1, 12/14/98)

3.2.12.2 Shadows cast from any proposed multistory structure shall be taken into consideration as to their effect on adjacent properties. Where such shadows adversely affect solar energy systems between the hours of 9:00 a.m. and 3:00 p.m., a site plan shall show that the multistory structure has been reoriented on the site to mitigate this effect or that other measures have been taken so as to minimize the adverse effects of the shading. The development potential of any property shall not be reduced by compliance with this Section. (See Illustration  3.2.12.2.)

3.2.13 STREETS. Streets shall be designed in accordance with the adopted Major Streets and Routes (MS&R) Plan and Development Standard 3-01.0. The Street Development Standard provides the minimum street design and installation standards necessary to accomplish the following.

  • Provide for streets of suitable location, width, and improvement to accommodate vehicular, pedestrian, and bicycle traffic.
  • Afford adequate access for police, fire fighting, ambulance, paramedic, utility, sanitation, and street maintenance equipment.
  • Coordinate street improvements so as to achieve a convenient system and avoid undue hardship to adjoining properties.
  • Design the improvement and development of streets based on the functional classification system. The design values of the street depend on the volume and type of traffic, the length of the street, and whether or not it is a through street.

3.2.14 LOTS.

3.2.14.1 Minimum Requirements. All lots shall comply with the minimum requirements of the zoning district in which they are being developed, such as size, width, and depth necessary to provide building setbacks and buildable area.

3.2.14.2 Minimum Lot Size Exceptions. The following are excepted from the minimum lot size requirements of this  Chapter.

A. Parcels that are:

1. Exclusively and permanently restricted by plat, deed, or covenant for private use, such as, but not limited to, common areas for parking, recreation, open space, drainage, or detention or retention of stormwater; or

2. Dedicated to the public for parks, open space, or other similar public purposes, such as placement of well sites, electrical substations, or other utilities.

B. A lot which is less than the minimum lot area required by the applicable zoning district may be developed with a single-family dwelling if all of the following apply.

1. The lot was existing and of record on September 20, 1948, or was legally created under Pima County jurisdiction and of record at the time of annexation.

2. The lot is zoned for residential development.

3. The proposed development on the lot conforms to all other requirements of this Chapter.

3.2.14.3 MS&R Street Frontage. A lot with frontage on a street designated on the MS&R Plan shall be designed with sufficient width and depth so that motor vehicles can enter or leave the lot without backing out onto the MS&R street.

3.2.14.4 Lot Width at Street Frontage. If a lot has street frontage, the lot width at the street frontage must be of a size sufficient for the purposes of locating motor vehicle and pedestrian access improvements as required by the Land Use Code (LUC) or any applicable Street Development Standard or regulation.

3.2.14.5 Public Street Access. All lots shall be designed with legal access to a public street.

A. If a proposed lot does not have public street frontage, access must be provided by private street or access easement of sufficient size to accommodate motor vehicle and pedestrian access and public services as required for the type of development proposed for the lot.

B. If access is to be provided by an easement and the easement serves more than three (3) single-family homes or duplexes, the City may require the easement to be developed as a street or as a parking area access lane (PAAL). The determination as to whether a developed street or PAAL is required will be made at the time of review of the proposed land division based on the need for public services, such as utilities, refuse collection, and fire suppression, and on the projected average daily traffic (ADT).