The provisions of Section 1510 of IBC are adopted by reference with the following modifications:
1. Revise Section 15010.1 and its subsections to read:
"1510.1 General.
The provisions of this section shall govern the construction of unoccupied rooftop structures.
1510.1.1 Area limitation.
The combined area of parapet walls, unoccupied rooftop structures, rooftop access penthouses in accordance with Section 1510.2 and structures accessory to an occupiable rooftop in accordance with Section 1513.1.1 shall not exceed one-third the area of the supporting roof deck. Such rooftop structures shall not be required to be included in determining building height, number of stories above grade plane or building area in accordance with Chapter 2, nor shall the area of such rooftop structures be included in determining the fire areas specified in Section 901.7.
Exception: If the combined area of rooftop structures exceeds one-third the horizontal area of the supporting roof deck, the height and area of the rooftop structures shall be considered in determining building height, number of stories above grade plane, building area and fire area."
2. Revise Section 1510.2 and its subsections to read:
"1510.2 Mechanical penthouses.
Mechanical penthouses in compliance with Sections 1510.2.1 through 1510.2.5 shall be considered as a portion of the story directly below the roof deck on which such penthouses are located. Other penthouses shall be considered as an additional story of the building.
1510.2.1 Height above roof deck.
Mechanical penthouses shall not exceed 18 feet (5486 mm) in height above the roof deck as measured to the average height of the roof of the penthouse.
Exception: On buildings of Type I construction, mechanical penthouses shall be permitted to have a maximum height of 28 feet (8534 mm) above the roof deck.
1510.2.2 Use limitations.
Mechanical penthouses shall not be used for purposes other than the shelter of mechanical or electrical equipment, tanks, elevators and related machinery, or vertical shaft openings in the roof assembly.
1510.2.3 Weather protection.
Provisions such as louvers, louver blades or flashing shall be made to protect the mechanical and electrical equipment and the building interior from the elements.
1510.2.4 Type of construction.
Mechanical penthouses shall be constructed with walls, floors and roofs as required for the type of construction of the building on which such penthouses are built.
Exceptions:
1. On buildings of Type I and II-A construction, the exterior walls and roof decks of mechanical penthouses with a fire separation distance greater than 5 feet (1524 mm) and less than 20 feet (6096 mm) shall be noncombustible construction and permitted to have not less than a 1-hour fire-resistance rating. The exterior walls and roofs of mechanical penthouses with a fire separation distance of 20 feet (6096 mm) or greater shall be noncombustible construction and not be required to have a fire-resistance rating.
2. [Reserved.]
3. On buildings of Type III, IV or V construction, the exterior walls of mechanical penthouses with a fire separation distance greater than 5 feet (1524 mm) and less than 20 feet (6096 mm) shall be permitted to have not less than a 1-hour fire-resistance rating or a lesser fire- resistance rating as required by Table 602. On buildings of Type III, IV or VA construction, the exterior walls of mechanical penthouses with a fire separation distance of 20 feet (6096 mm) or greater shall be permitted to be of heavy timber construction complying with Sections 602.4 and 2304.11 or noncombustible construction and shall not be required to have a fire-resistance rating."
3. Revise Section 1510.3 to read:
"1510.3 Tanks.
Tanks having a capacity of more than 500 gallons (1893 L) located on the roof deck of a building shall be supported on masonry, reinforced concrete, steel or heavy timber construction complying with Section 2304.11 provided that, where such supports are located in the building above the lowest story, the support shall have a fire-resistance rating as required for Type IA construction."
4. Revise Section 1510.5 and its subsections to read:
"1510.5 Towers, spires, minarets, domes and cupolas.
Towers, spires, minarets, domes, cupolas, and similar features shall be of a type of construction having fire- resistance ratings not less than required for the building on top of which such feature is built. Such features greater than 85 feet (25 908 mm) in height above grade plane as measured to the highest point on such feature, and either greater than 200 square feet (18.6 m2) in horizontal area or used for any purpose other than a belfry or an architectural embellishment, shall be constructed of and supported on Type I or IIA construction.
1510.5.1 Noncombustible construction required.
Features greater than 60 feet (18 288 mm) in height above the highest point at which such feature contacts the roof as measured to the highest point on such feature, or that exceeds 200 square feet (18.6
m2) in area at any horizontal section, or which is intended to be used for any purpose other than a belfry or architectural embellishment, or is located on the top of a building greater than 50 feet (1524 mm) in building height shall be constructed of and supported by noncombustible materials and shall be separated from the building below by construction having a fire-resistance rating of not less than 1.5 hours with openings protected in accordance with Section 711. Such features located on the top of a building greater than 50 feet (15 240 mm) in building height shall be supported by noncombustible construction.
1510.5.2 Enclosed features
Enclosed features shall have exterior walls constructed as required for the building on top of which such features are built. The roof covering of features shall be not less than the same class of roof covering required for the building on top of which the feature is located."
5. Revise Section 1510.6 by replacing "5 feet (1524 mm)" with "15 feet (4572 mm)."
6. Revise the exception to Section 1510.6.1 by replacing "Type IA" with "Type I."
7. Revise Section 1510.6.2 to read:
"1510.6.2 Type I, II, III or IV construction.
Regardless of the requirements in Section 1510.6, mechanical equipment screens that are located on the roof decks of buildings of Type I, II, III or IV construction shall be permitted to be constructed of combustible materials in accordance with the following limitation: the fire separation distance shall be not less than 20 feet (6096 mm) and the height of the mechanical equipment screen above the roof deck shall not exceed 4 feet (1219 mm) as measured to the highest point on the mechanical equipment screen."
8. Revise Section 1510.6.3 to read:
"1510.6.3 Type V construction.
The height of mechanical equipment screens located on the roof decks of buildings of Type V construction, as measured from grade plane to the highest point on the mechanical equipment screen, shall not exceed the maximum building height allowed for the building by other provisions of this code."
9. Revise Section 1510.7 to read:
"1510.7 Photovoltaic panels and modules.
Rooftop-mounted photovoltaic panels and modules shall be designed in accordance with this section and the Chicago Fire Prevention Code."
10. Revise Section 1510.8 by replacing "Sections 1510.8.1 through 1510.8.5, as applicable" with "Section 1510.8.1."
11. Delete Sections 1510.8.2, 1510.8.3, 1510.8.4, and 1510.8.5.
(Amend Coun. J. 2-19-20, p. 14473, Art. II, § 70)