13-48-040 Exceptions to height limitations.

   (a)   Towers, steeples and similar structures, not intended or used for human occupancy and not exceeding in area 25 percent of the ground area of the building on which they are erected, may be erected to a height not exceeding 60 feet above the height limitations established in Section 13-48-030, except that water tanks or towers for fire protection purposes, whether supported directly on buildings or on independent ground structures, may be erected to a height not exceeding 60 feet above the maximum height of the building or group of buildings which is served or protected by such water tanks; provided that the height limitation of such structures constructed on a building in the Wrigley Field Adjacent Area in which special club license is located shall be as provided in Chapter 4-388.

(Prior code § 51-1.3; Amend Coun. J. 1-11-06, p. 68371, § 3)

13-48-050 Area limitations.

   Every building or structure hereafter erected shall conform to the requirements of area limitations as provided in Sections 13-48-060 to 13-48-090, inclusive.

(Prior code § 51-2)

13-48-060 Application of area limitations.

   (a)   The maximum floor area of buildings shall be governed by the occupancy classification, the number of stories and the type of construction as required in this section.

   (b)   Nothing in this section shall be interpreted to prevent the application of other area restrictions required by the Chicago Zoning Ordinance.

   (c)   In the application of area limitations, each part of a building separated from all other parts of the building by fire walls as defined in Section 15-8-020 shall be deemed to be a separate building.

   (d)   The area of a basement shall not exceed the maximum floor area permitted for the building; provided, however, that every basement exceeding 40,000 square feet in area shall be subdivided by fire walls complying with the requirements of Section 15-8-010 into areas not exceeding 40,000 square feet. The maximum undivided area of a basement may be increased to 80,000 square feet when the building is equipped throughout with an approved automatic sprinkler system in accordance with Chapter 15-16 of the municipal code.

(Prior code § 51-2.4; Amend Coun. J. 2-13-85, p. 13526)

13-48-070 Area limitations – One-story buildings.

   Except as provided in Section 13-48-090, the floor area of any one-story building shall not exceed the basic areas established in Table 13-48-070. (See Table 13-48-070.)

(Prior code § 51-2.2)

Table 13-48-070 Basic Maximum Areas – One Story Buildings (Square Feet)
Occupancy Classification		Construction Type
		I-A	I-B	I-C	II	III-A	III-B	III-C	IV-A	IV-B
A.	Residential	NL	NL	24,000	10,000	10,000	10,000	8,000	5,000	3,000
B.	Institutional	NL	NL	16,000	6,000	6,000	6,000	NP	NP	NP
C-1.	Large	NL	NL	NL(a)	20,000(a)	25,000(a)	20,000(a)	NP	NP	NP
	Assembly			24,000	8,000	10,000	8,000
C-2.	Small Assembly	NL	NL	NL(a)	20,000(a)	20,000(a)	20,000(a)	NP(b)	NP(b)	NP(b)
				24,000	8,000	10,000	8,000	5,000(c)	3,000(c)	1,500(c)
C-3.	Schools	NL	NL	NL(a)	20,000(a)	25,000(a)	20,000(a)
				24,000	8,000	10,000	8,000	6,000	4,000	2,000
D.	Open Air Assembly	Maximum areas established in Chapter 13-88
E.	Business	NL	NL	NL	NL(a)(d)	NL(a)(d)	NL(a)(d)	10,000	6,000	4,000
					12,000	15,000	12,000
F.	Mercantile	NL	NL	NL	NL(a)(d)	NL(a)(d)	NL(a)(d)	8,000	5,000	3,000
					10,000	12,000	10,000
G-1.	Industrial	NL	NL	NL	NL(a)	NL(a)	NL(a)	10,000	6,000	4,000
	Low Hazard				12,000	15,000	12,000
G-2.	Industrial	NL	NL	NL	NL(a)(d)	NL(a)(d)	NL(a)(d)	8,000	5,000	3,000
	Moderate Hazard				10,000	12,000	10,000
H-1.	Storage	NL	NL	NL	NL(a)	NL(a)	NL(a)	10,000	6,000	4,000
	Low Hazard				12,000	15,000	12,000
H-2.	Storage	NL	NL	NL	NL(a)(d)	NL(a)(d)	NL(a)(d)	8,000	5,000	3,000
	Moderate Hazard				10,000	12,000	10,000
H-3.	Garages	40,000	35,000	30,000	15,000	20,000	15,000	10,000	NP	NP
I.	Hazardous Use		Maximum areas established in Chapter 13-112
J.	Miscellaneous Buildings and Structures			Maximum areas established in Chapter 13-96
NOTES:
NL – Not Limited. In buildings of unlimited area, no portion of such buildings shall be more than 300 feet from an exterior wall facing an open, accessible space not less than 30 feet wide consisting of a public way, railroad right-of-way, waterway, park or a court, accessible from a public way; except that such maximum distance from an exterior wall may not be more than 500 feet in buildings of low hazard industrial or low hazard storage units.
NP – Not Permitted.
(a)   These areas permitted only when the first floor construction and all construction below the first floor level is of Type I-A construction.
(b)   Theaters.
(c)   Assembly units other than theaters.
See Section 13-48-090 for allowable increase in areas for frontage and automatic sprinkler equipment.
(d)   All buildings of Type II and III-A and III-B construction having unlimited areas shall be provided with an automatic sprinkler system.

 

13-48-080 Area limitations – Multi-story buildings.

   Except as provided in Section 13-48-090, the area of any floor of a building exceeding one story in height shall not exceed the basic areas established in Table 13-48-080, multiplied by the following factors:

Number of Stories   Factor

2   1.00

3   0.90

4   0.85

5   0.80

6   0.75

7   0.70

8 or more   0.65

(See Table 13-48-080.)

(Prior code § 51-2.3)

Table 13-48-080 Basic Maximum Areas – Multi-story Buildings (Square Feet)
Occupancy Classification		Construction Type
		I-A	I-B	I-C	II	III-A	III-B	III-C	IV-A	IV-B
A.	Residential	NL	NL	20,000	NP	8,000	8,000	6,000	4,000	2,000
B.	Institutional	30,000	16,000	12,000	NP	NP	NP	NP	NP	NP
C-1.	Assembly	NL	NL	16,000	NP	6,000	6,000	NP	NP	NP
C-2.	Small Assembly	NL	NL	16,000	NP	6,000	6,000	NP	NP	NP
C-3.	Schools	NL	NL	16,000	NP	6,000	6,000	NP	NP	NP
D.	Open Air Assembly		Maximum areas established in Chapter 55
E.	Business	NL	NL	20,000	NP	10,000	10,000	8,000	NP	NP
F.	Mercantile	30,000	20,000	16,000	NP	8,000	8,000	6,000	NP	NP
G-1.	Industrial Low-Hazard	NL	30,000	20,000	10,000	10,000	10,000	8,000	NP	NP
G-2.	Industrial Moderate- Hazard	30,000	20,000	16,000	NP	8,000	8,000	6,000	NP	NP
H-1.	Storage Low-Hazard	NL	30,000	20,000	10,000	10,000	10,000	8,000	NP	NP
H-2.	Storage Moderate- Hazard	30,000	20,000	16,000	NP	8,000	8,000	6,000	NP	NP
H-3.	Garages	25,000	15,000	10,000	NP	6,000	6,000	NP	NP	NP
I.	Hazardous-Use		Maximum areas established in Chapter 60
J.	Miscellaneous Buildings & Structures		Maximum areas established in Chapter 61
NOTES:
NL – Not Limited. In buildings of unlimited area, no portion of such buildings shall be more than 300 feet from an exterior wall facing an open, accessible space not less than 30 feet wide consisting of a public way, railroad right-of-way, waterway, park or a court, accessible from a public way; except that such maximum distance from an exterior wall may not be more than 500 feet in buildings of low hazard industrial or low hazard storage units.
NP – Not Permitted.
See Section 13-48-090 for allowable increase in areas for frontage and automatic sprinkler equipment.

 

13-48-090 Exceptions to area limitations.

   (a)   Area Increase for Street Frontage and Separation. In buildings except institutional and assembly units, when more than 25 percent of the perimeter of a building faces a public street or other open area not less than 30 feet wide accessible to a public street, the allowable basic floor area may be increased as follows:

      (1)   When (I) equals the percentage by which areas established in Sections 13-48-070 and 13-48-080 may be increased, “P” equals the perimeter of the building and “F” equals the frontage, the following formula shall be used:

 

I	=	200F P	–	50

 

      Such increase shall not exceed 100 percent of the established basis floor area.

   (b)   Area Increase for Sprinklers. Floor areas may be increased 100 percent of the areas established in Sections 13-48-070, 13-48-080 and subsection (a) of this section when the building is equipped throughout with an approved automatic sprinkler system; provided that the provisions of this subsection shall not apply to a building in the Wrigley Field Adjacent Area in which a special club license is located.

   (c)   Area Increase for Two-Source Water Supply Sprinkler Systems. Floor areas of buildings, except Class A Residential and Class B Institutional, may be increased an additional 50 percent of the areas established in subsection (b) of this section when the automatic sprinkler system is supervised and provided with a two-source water supply, one of which shall be provided with an emergency power supply; provided that the provisions of this subsection shall not apply to a building in the Wrigley Field Adjacent Area in which a special club license is located.

   (d)   Areas of Basements. The area of a basement shall not exceed the maximum floor area permitted for the building; provided, however, that every basement exceeding 40,000 square feet in area shall be subdivided by fire walls complying with the requirements of Section 15-8-010 into areas not exceeding 40,000 square feet.

   (e)   Type III Schools. C-3 school area limitations are not applicable to Type III schools. 8,000 square feet or less in buildings of mixed occupancies of construction Types III or better.

   (f)   The areas of the individual buildings serviced by the covered mall, exit passages and/or the exterior shall each comply with the allowable areas established in Sections 13-48-070 and 13-48-080 with applicable increases as allowed in this Section 13-48-090.

      (1)   The entire building shall be 100 percent sprinklered. The sprinkler system shall be supervised and provided with a two-source water supply.

      (2)   The covered mall area is to be equipped with approved smoke activated smoke and heat venting devices in the roof. The venting area shall be sized to provide one square foot of vent area for each 100 square feet of the largest atrium floor opening, or mechanical exhaust of 2 cfm for each square foot of the largest atrium opening. Minimum size of vent opening shall be ten square feet or 2,000 cfm mechanical exhaust. Location and installation of vents to be approved by the fire commissioner.

      (3)   The area separations may be eliminated as presently required in Section 15-8-240(a)(2) of this Code.

(Prior code § 51-2.4; Amend Coun. J. 1-11-06, p. 68371, § 3; Amend Coun. J. 5-18-16, p. 24131, § 32)