Section 1607 — California Building Code (Title 24, Part 2)

1607.1 General.¶

Live loads are those loads defined in Chapter 2 of this code.

1607.2 Loads not specified.¶

For occupancies or uses not designated in Table 1607.1, the live load shall be determined in accordance with a method approved by the building official.

1607.3 Uniform live loads.¶

The live loads used in the design of buildings and other structures shall be the maximum loads expected by the intended use or occupancy but shall not be less than the minimum uniformly distributed live loads given in Table 1607.1.

1607.4 Concentrated live loads.¶

Floors, roofs and other similar surfaces shall be designed to support the uniformly distributed live loads prescribed in Section 1607.3 or the concentrated live loads, given in Table 1607.1, whichever produces the greater load effects. Unless otherwise specified, the indicated concentration shall be assumed to be uniformly distributed over an area of 2 ¹ /2 feet by 2 ¹ /2 feet (762 mm by 762 mm) and shall be located so as to produce the maximum load effects in the structural members.

1607.5 Partition loads.¶

In office buildings and in other buildings where partition locations are subject to change, provisions for partition weight shall be made, whether or not partitions are shown on the construction documents, unless the specified live load is 80 psf (3.83 kN/m ² ) or greater. The partition load shall be not less than a uniformly distributed live load of 15 psf (0.72 kN/m ² ).

1607.6 Helipads.¶

Helipads shall be designed for the following live loads:

A uniform live load, L, as specified in Items 1.1 and 1.2. This load shall not be reduced.

1.1. 40 psf (1.92 kN/m ² ) where the design basis helicopter has a maximum take-off weight of 3,000 pounds (13.35 kN) or less.

1.2. 60 psf (2.87 kN/m ² ) where the design basis helicopter has a maximum take-off weight greater than 3,000 pounds (13.35 kN).

A single concentrated live load, L, of 3,000 pounds (13.35 kN) applied over an area of 4.5 inches by 4.5 inches (114 mm by 114 mm) and located so as to produce the maximum load effects on the structural elements under consideration. The concentrated load is not required to act concurrently with other uniform or concentrated live loads.
Two single concentrated live loads, L, 8 feet (2438 mm) apart applied on the landing pad (representing the helicopter’s two main landing gear, whether skid type or wheeled type), each having a magnitude of 0.75 times the maximum take-off weight of the helicopter, and located so as to produce the maximum load effects on the structural elements under consideration. The concentrated loads shall be applied over an area of 8 inches by 8 inches (203 mm by 203 mm) and are not required to act concurrently with other uniform or concentrated live loads.

Landing areas designed for a design basis helicopter with maximum take-off weight of 3,000-pounds (13.35 kN) shall be identified with a 3,000 pound (13.34 kN) weight limitation. The landing area weight limitation shall be indicated by the numeral “3” (kips) located in the bottom right corner of the landing area as viewed from the primary approach path. The indication for the landing area weight limitation shall be a minimum 5 feet (1524 mm) in height.

1607.7 Heavy vehicle loads.¶

Floors and other surfaces that are intended to support vehicle loads greater than a 10,000pound (4536 kg) gross vehicle weight rating shall comply with Sections 1607.7.1 through 1607.7.5.

1607.7.1 Loads. Where any structure does not restrict access for vehicles that exceed a 10,000-pound (4536 kg) gross vehicle weight rating, those portions of the structure subject to such loads shall be designed using the vehicular live loads, including consideration of impact and fatigue, in accordance with the codes and specifications required by the jurisdiction having authority for the design and construction of the roadways and bridges in the same location of the structure.

1607.7.2 Fire truck and emergency vehicles. Where a structure or portions of a structure are accessed and loaded by fire department access vehicles and other similar emergency vehicles, the structure shall be designed for the greater of the following loads:

The actual operational loads, including outrigger reactions and contact areas of the vehicles as stipulated and approved by the building official.
The live loading specified in Section 1607.7.1.

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Copyright © 2019 ICC. ALL RIGHTS RESERVED. Accessed by Kevin Day (kevin.day@dgs.ca.gov), (California Building Standards Commission) Order Number #100735044 on Jul 24, 2019 03:54 PM (PDT) pursuant to License Agreement with ICC. No further reproduction or distribution authorized. Single user only, copying and networking prohibited. ANY UNAUTHORIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT, AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.

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TABLE 1607.1 MINIMUM UNIFORMLY DISTRIBUTED LIVE LOADS, L0 ,

AND MINIMUM CONCENTRATED LIVE LOADS ^g

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TABLE 1607.1—continued MINIMUM UNIFORMLY DISTRIBUTED LIVE LOADS, L0 ,

AND MINIMUM CONCENTRATED LIVE LOADS ^g

OCCUPANCY OR USE	UNIFORM (psf)	CONCENTRATED (pounds)	OCCUPANCY OR USE	UNIFORM (psf)	CONCENTRATED (pounds)
1. Apartments (see residential)	—	—	23. Penal institutions
2. Access floor systems Office use Computer use	50 100	2,000 2,000	Cell blocks Corridors	40 100	—
3. Armories and drill rooms 4. Assembly areas Fixed seats (fastened to floor) Follow spot, projections and control rooms Lobbies Movable seats Stage floors Platforms (assembly) Other assembly areas	150n 60m 50 100m 100m 150n 100m 100m	— —	24. Recreational uses: Bowling alleys, poolrooms and similar uses Dance halls and ballrooms Gymnasiums Ice skating rink Reviewing stands, grandstands and bleachers Roller skating rink Stadiums and arenas with fixed seats (fastened to floor)	75m 100m 100m 250n 100c, m 100m 60c, m	—
5. Balconies and decksh	1.5 times the live load for the area served, not required to exceed 100	—	25. Residential One- and two-family dwellings Uninhabitable attics without storagei	10
6. Catwalks 7. Cornices	40 60	300 —	Uninhabitable attics with storagei, j, k Habitable attics and sleeping areask Canopies, including marquees	20 30 20	—
8. Corridors First floor Other floors	100 Same as occupancy	—	All other areas Hotels and multifamily dwellings Private rooms and corridors serving them	40 40
	served except as indicated		Public roomsm and corridors serving them	100
9. Dining rooms and restaurants 10. Dwellings (see residential) 11. Elevator machine room and controlroom grating (on area of 2 inches by 2 inches) 12. Finish light floor plate construction (on area of 1 inch by 1 inch)	100m — — —	— — 300 200	26. Roofs All roof surfaces subject to main- tenance workers Awnings and canopies: Fabric construction supported by a skeleton structure All other construction, except one-	5m	300
13. Fire escapes On single-family dwellings only 14. Garages (passenger vehicles only) Trucks and buses 15. Handrails, guards and grab bars 16. Helipads 17. Hospitals Corridors above first floor Operating rooms, laboratories Patient rooms	100 40 — 40o Note a See Section 1607.7 See Section 1607.8 See Section 1607.6 80 60 40 1,000 1,000 1,000	100 40 — 40o Note a See Section 1607.7 See Section 1607.8 See Section 1607.6 80 60 40 1,000 1,000 1,000	and two-family dwellings Ordinary flat, pitched, and curved roofs (that are not occupiable) Primary roof members exposed to a work floor Single panel point of lower chord of roof trusses or any point along primary structural members supporting roofs over manufac- turing, storage warehouses, and repair garages All other primary roof members	20 20	2,000 300
18. Hotels (see residential)	—	—	Occupiable roofs:
19. Libraries Corridors above first floor Reading rooms Stack rooms 20. Manufacturing Heavy Light	80 60 150b, n 250n 125n	1,000 1,000 1,000 3,000 2,000	Roof gardens Assembly areas All other similar areas 27. Schools Classrooms Corridors above first floor First-floor corridors	100 100m Note 1 40 80 100	Note 1 1,000 1,000 1,000
21. Marquees, except one- and two-family dwellings 22. Office buildings Corridors above first floor File and computer rooms shall be	75 80 —	— 2,000 —	28. Scuttles, skylight ribs and accessible ceilings 29. Sidewalks, vehicular driveways and yards, subject to trucking	— 250d, n	200 8,000e
designed for heavier loads based on anticipated occupancy Lobbies and first-floor corridors Offices	100 50	2,000 2,000	(continued)	(continued)

(continued)

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TABLE 1607.1—continued MINIMUM UNIFORMLY DISTRIBUTED LIVE LOADS, L0 ,

AND MINIMUM CONCENTRATED LIVE LOADS ^g

TABLE 1607.1—continued MINIMUM UNIFORMLY DISTRIBUTED LIVE LOADS, Lo ,

AND MINIMUM CONCENTRATED LIVE LOADS ^g

OCCUPANCY OR USE	UNIFORM (psf)	CONCENTRATED (pounds)
30. Stairs and exits One- and two-family dwellings All other	40 100	300f 300f
31. Storage warehouses (shall be designed for heavier loads if required for anticipated storage) Heavy Light	250n 125n	—
32. Stores Retail First floor Upper floors Wholesale, all floors	100 75 125n	1,000 1,000 1,000
33. Vehicle barriers	See Section 1607.9	See Section 1607.9
34. Walkways and elevated platforms (other than exitways)	60	—
35. Yards and terraces, pedestrians	100m	—
36._ [OSHPD 1R, 2 & 5]_Storage racks and wall-hung cabinets.	Total loadsp

For SI: 1 inch = 25.4 mm, 1 square inch = 645.16 mm ²,

1 square foot = 0.0929 m ², 1 pound per square foot = 0.0479 kN/m ², 1 pound = 0.004448 kN, 1 pound per cubic foot = 16 kg/m ³ . a. Floors in garages or portions of buildings used for the storage of motor

vehicles shall be designed for the uniformly distributed live loads of this table or the following concentrated loads: (1) for garages restricted to passenger vehicles accommodating not more than nine passengers, 3,000 pounds acting on an area of 4 ¹ /2 inches by 4 ¹ /2 inches; (2) for mechanical parking structures without slab or deck that are used for storing passenger vehicles only, 2,250 pounds per wheel. b. The loading applies to stack room floors that support nonmobile, double faced library book stacks, subject to the following limitations:

The nominal book stack unit height shall not exceed 90 inches.
The nominal shelf depth shall not exceed 12 inches for each face.
Parallel rows of double-faced book stacks shall be separated by aisles not less than 36 inches wide. c. Design in accordance with ICC 300. d. Other uniform loads in accordance with an approved method containing

provisions for truck loadings shall be considered where appropriate. e. The concentrated wheel load shall be applied on an area of 4.5 inches by

4.5 inches. f. The minimum concentrated load on stair treads shall be applied on an area

of 2 inches by 2 inches. This load need not be assumed to act concurrently with the uniform load. g. Where snow loads occur that are in excess of the design conditions, the

structure shall be designed to support the loads due to the increased loads caused by drift buildup or a greater snow design determined by the building official (see Section 1608). h. See Section 1604.8.3 for decks attached to exterior walls. i. Uninhabitable attics without storage are those where the maximum clear

height between the joists and rafters is less than 42 inches, or where there are not two or more adjacent trusses with web configurations capable of accommodating an assumed rectangle 42 inches in height by 24 inches in width, or greater, within the plane of the trusses. This live load need not be assumed to act concurrently with any other live load requirements.

(continued)

j. Uninhabitable attics with storage are those where the maximum clear

height between the joists and rafters is 42 inches or greater, or where there are two or more adjacent trusses with web configurations capable of accommodating an assumed rectangle 42 inches in height by 24 inches in width, or greater, within the plane of the trusses.

The live load need only be applied to those portions of the joists or truss bottom chords where both of the following conditions are met:

i. The attic area is accessible from an opening not less than 20 inches

in width by 30 inches in length that is located where the clear height in the attic is not less than 30 inches. ii. The slopes of the joists or truss bottom chords are not greater than

two units vertical in 12 units horizontal. The remaining portions of the joists or truss bottom chords shall be designed for a uniformly distributed concurrent live load of not less than 10 pounds per square foot. k. Attic spaces served by stairways other than the pull-down type shall be

designed to support the minimum live load specified for habitable attics and sleeping rooms. l. Areas of occupiable roofs, other than roof gardens and assembly areas,

shall be designed for appropriate loads as approved by the building official. Unoccupied landscaped areas of roofs shall be designed in accordance with Section 1607.13.3. m. Live load reduction is not permitted.

n. Live load reduction is only permitted in accordance with Section

1607.11.1.2 or Item 1 of Section 1607.11.2. o. Live load reduction is only permitted in accordance with Section

1607.11.1.3 or Item 2 of Section 1607.11.2. p. [OSHPD 1R, 2 & 5] The minimum vertical design live load shall be as

follows: Paper media: 12-inch-deep (305 mm) shelf 33 pounds per lineal foot (482 N/m) 15-inch-deep (381 mm) shelf 41 pounds per lineal foot (598 N/m), or 33 pounds per cubic foot (5183 N/m ³ ) per total volume of the rack or cabinet, whichever is less. Film media: 18-inch-deep (457 mm) shelf 100 pounds per lineal foot (1459 N/m), or 50 pounds per cubic foot (7853 N/m ³ ) per total volume of the rack or cabinet, whichever is less. Other media:

20 pounds per cubic foot (311 N/m ³ ) or 20 pounds per square foot (958 Pa), whichever is less, but not less than actual loads.

1607.7.3 Heavy vehicle garages. Garages designed to accommodate vehicles that exceed a 10,000-pound (4536 kg) gross vehicle weight rating, shall be designed using the live loading specified by Section 1607.7.1. For garages the design for impact and fatigue is not required.

Exception: The vehicular live loads and load placement are allowed to be determined using the actual vehicle weights for the vehicles allowed onto the garage floors, provided that such loads and placement are based on rational engineering principles and are approved by the building official, but shall be not less than 50 psf (2.9 kN/m ² ). This live load shall not be reduced.

1607.7.4 Forklifts and movable equipment. Where a structure is intended to have forklifts or other movable equipment present, the structure shall be designed for the

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total vehicle or equipment load and the individual wheel loads for the anticipated vehicles as specified by the owner of the facility. These loads shall be posted in accordance with Section 1607.7.5.

1607.7.4.1 Impact and fatigue. Impact loads and fatigue loading shall be considered in the design of the supporting structure. For the purposes of design, the vehicle and wheel loads shall be increased by 30 percent to account for impact.

1607.7.5 Posting. The maximum weight of vehicles allowed into or on a garage or other structure shall be posted by the owner or the owner’s authorized agent in accordance with Section 106.1.

1607.8 Loads on handrails, guards, grab bars¶

shower seats, dressing room bench seats and seats. Handrails and guards shall be designed and constructed for the structural loading conditions set forth in Section 1607.8.1. Grab bars, shower seats and accessible benches shall be designed and constructed for the structural loading conditions set forth in Section 1607.8.2.

1607.8.1 Handrails and guards. Handrails and guards shall be designed to resist a linear load of 50 pounds per linear foot (plf) (0.73 kN/m) in accordance with Section 4.5.1.1 of ASCE 7. Glass handrail assemblies and guards shall comply with Section 2407.

Exceptions:

For one- and two-family dwellings, only the single concentrated load required by Section 1607.8.1.1 shall be applied.
In Group I-3, F, H and S occupancies, for areas that are not accessible to the general public and that have an occupant load less than 50, the minimum load shall be 20 pounds per foot (0.29 kN/m).

1607.8.1.1 Concentrated load. Handrails and guards shall be designed to resist a concentrated load of 200 pounds (0.89 kN) in accordance with Section 4.5.1.1 of ASCE 7.

1607.8.1.2 Intermediate rails. Intermediate rails (all those except the handrail), balusters and panel fillers shall be designed to resist a concentrated load of 50 pounds (0.22 kN) in accordance with Section 4.5.1.1 of ASCE 7.

1607.8.2 Grab bars, shower seats and dressing room bench seats. Grab bars, shower seats and dressing room bench seats shall be designed to resist a single concentrated load of 250 pounds (1.11 kN) applied in any direction at any point on the grab bar or seat so as to produce the maximum load effects. [DSA-AC & HCD 1-AC] See Chapter 11A, Section 1127A.4, and Chapter 11B, Sections 11B-609.8, 11B-610.4 and 11B-903.6 for grab bars, shower seats and dressing room bench seats, as applicable.

1607.9 Vehicle barriers.¶

Vehicle barriers for passenger vehicles shall be designed to resist a concentrated load of 6,000 pounds (26.70 kN) in accordance with Section 4.5.3 of ASCE 7. Garages accommodating trucks and buses shall be

STRUCTURAL DESIGN

designed in accordance with an approved method that contains provisions for traffic railings.

1607.10 Impact loads.¶

The live loads specified in Sections 1607.3 through 1607.9 shall be assumed to include adequate allowance for ordinary impact conditions. Provisions shall be made in the structural design for uses and loads that involve unusual vibration and impact forces.

1607.10.1 Elevators. Members, elements and components subject to dynamic loads from elevators shall be designed for impact loads and deflection limits prescribed by ASME A17.1/CSA B44.

1607.10.2 Machinery. For the purpose of design, the weight of machinery and moving loads shall be increased as follows to allow for impact:

Light machinery, shaft- or motor-driven, 20 percent.
Reciprocating machinery or power-driven units, 50 percent.

Percentages shall be increased where specified by the manufacturer.

1607.10.3 Elements supporting hoists for façade access and building maintenance equipment. In addition to any other applicable live loads, structural elements that support hoists for façade access and building maintenance equipment shall be designed for a live load of 2.5 times the rated load of the hoist or the stall load of the hoist, whichever is larger.

1607.10.4 Fall arrest and lifeline anchorages. In addition to any other applicable live loads, fall arrest and lifeline anchorages and structural elements that support these anchorages shall be designed for a live load of not less than 3,100 pounds (13.8 kN) for each attached lifeline, in every direction that a fall arrest load can be applied.

1607.11 Reduction in uniform live loads.¶

Except for uniform live loads at roofs, all other minimum uniformly distributed live loads, Lo, in Table 1607.1 are permitted to be reduced in accordance with Section 1607.11.1 or 1607.11.2. Uniform live loads at roofs are permitted to be reduced in accordance with Section 1607.13.2.

1607.11.1 Basic uniform live load reduction. Subject to the limitations of Sections 1607.11.1.1 through 1607.11.1.3 and Table 1607.1, members for which a value of KLLAT is 400 square feet (37.16 m ² ) or more are permitted to be designed for a reduced uniformly distributed live load, L, in accordance with the following equation:

(Equation 16-23)

For SI:

where: L = Reduced design live load per square foot (m ² ) of

area supported by the member. Lo = Unreduced design live load per square foot (m ² ) of

area supported by the member (see Table 1607.1).

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STRUCTURAL DESIGN

KLL = Live load element factor (see Table 1607.11.1). AT = Tributary area, in square feet (m ² ).

L shall be not less than 0.50 Lo for members supporting one floor and L shall be not less than 0.40 Lo for members supporting two or more floors.

1607.11.1.1 One-way slabs. The tributary area, AT, for use in Equation 16-23 for one-way slabs shall not exceed an area defined by the slab span times a width normal to the span of 1.5 times the slab span.

1607.11.1.2 Heavy live loads. Live loads that exceed 100 psf (4.79 kN/m ² ) shall not be reduced.

Exceptions:

The live loads for members supporting two or more floors are permitted to be reduced by not greater than 20 percent, but the live load shall be not less than L as calculated in Section 1607.11.1.
For uses other than storage, where approved, additional live load reductions shall be permitted where shown by the registered design professional that a rational approach has been used and that such reductions are warranted.

1607.11.1.3 Passenger vehicle garages. The live loads shall not be reduced in passenger vehicle garages.

Exception: The live loads for members supporting two or more floors are permitted to be reduced by not greater than 20 percent, but the live load be shall be not less than L as calculated in Section 1607.11.1.

TABLE 1607.11.1 LIVE LOAD ELEMENT FACTOR, KLL

ELEMENT	K LL
Interior columns Exterior columns without cantilever slabs	4 4
Edge columns with cantilever slabs	3
Corner columns with cantilever slabs Edge beams without cantilever slabs Interior beams	2 2 2
Members not previously identified including: Edge beams with cantilever slabs Cantilever beams One-way slabs Two-way slabs Members without provisions for continuous shear transfer normal to their span	1

1607.11.2 Alternative uniform live load reduction. As an alternative to Section 1607.11.1 and subject to the limitations of Table 1607.1, uniformly distributed live loads are permitted to be reduced in accordance with the following provisions. Such reductions shall apply to slab systems, beams, girders, columns, piers, walls and foundations.

A reduction shall not be permitted where the live load exceeds 100 psf (4.79 kN/m ² ) except that the

design live load for members supporting two or more floors is permitted to be reduced by not greater than 20 percent.

Exception: For uses other than storage, where approved, additional live load reductions shall be permitted where shown by the registered design professional that a rational approach has been used and that such reductions are warranted.

A reduction shall not be permitted in passenger vehicle parking garages except that the live loads for members supporting two or more floors are permitted to be reduced by not greater than 20 percent.
For live loads not exceeding 100 psf (4.79 kN/m ² ), the design live load for any structural member supporting 150 square feet (13.94 m ² ) or more is permitted to be reduced in accordance with Equation 16-24.
For one-way slabs, the area, A, for use in Equation 16-24 shall not exceed the product of the slab span and a width normal to the span of 0.5 times the slab span.

R = 0.08( A – 150) (Equation 16-24)

For SI: R = 0.861( A – 13.94)

Such reduction shall not exceed the smallest of:

40 percent for members supporting one floor.
60 percent for members supporting two or more floors.
R as determined by the following equation:

R = 23.1(1+ D/Lo ) (Equation 16-25)

where:

A = Area of floor supported by the member, square

feet (m ² ). D = Dead load per square foot (m ² ) of area

supported. Lo = Unreduced live load per square foot (m ² ) of

area supported.

R = Reduction in percent.

1607.12 Distribution of floor loads.¶

Where uniform floor live loads are involved in the design of structural members arranged so as to create continuity, the minimum applied loads shall be the full dead loads on all spans in combination with the floor live loads on spans selected to produce the greatest load effect at each location under consideration. Floor live loads are permitted to be reduced in accordance with Section 1607.11.

1607.13 Roof loads.¶

The structural supports of roofs and marquees shall be designed to resist wind and, where applicable, snow and earthquake loads, in addition to the dead load of construction and the appropriate live loads as prescribed in this section, or as set forth in Table 1607.1. The live loads acting on a sloping surface shall be assumed to act vertically on the horizontal projection of that surface.

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1607.13.1 Distribution of roof loads. Where uniform roof live loads are reduced to less than 20 psf (0.96 kN/m ² ) in accordance with Section 1607.13.2.1 and are applied to the design of structural members arranged so as to create continuity, the reduced roof live load shall be applied to adjacent spans or to alternate spans, whichever produces the most unfavorable load effect. See Section 1607.13.2 for reductions in minimum roof live loads and Section 7.5 of ASCE 7 for partial snow loading.

1607.13.2 General. The minimum uniformly distributed live loads of roofs and marquees, Lo, in Table 1607.1 are permitted to be reduced in accordance with Section 1607.13.2.1.

1607.13.2.1 Ordinary roofs, awnings and canopies. Ordinary flat, pitched and curved roofs, and awnings and canopies other than of fabric construction supported by a skeleton structure, are permitted to be designed for a reduced uniformly distributed roof live load, Lr, as specified in the following equations or other controlling combinations of loads as specified in Section 1605, whichever produces the greater load effect.

In structures such as greenhouses, where special scaffolding is used as a work surface for workers and materials during maintenance and repair operations, a lower roof load than specified in the following equations shall not be used unless approved by the building official. Such structures shall be designed for a minimum roof live load of 12 psf (0.58 kN/m ² ).

Lr = Lo R 1 R 2 (Equation 16-26)

where: 12 ≤ Lr ≤ 20 For SI: Lr = LoR 1 R 2 where: 0.58 ≤ Lr ≤ 0.96 Lo = Unreduced roof live load per square foot (m ² ) of

horizontal projection supported by the member (see Table 1607.1). Lr = Reduced roof live load per square foot (m ² ) of

horizontal projection supported by the member. The reduction factors R 1 and R 2 shall be determined as follows:

R 1 = 1 for At ≤ 200 square feet (18.58 m ² )

(Equation 16-27) R 1 = 1.2 - 0.001 At for 200 square feet

< At < 600 square feet (Equation 16-28)

For SI: 1.2 - 0.011 At for 18.58 square meters < At <

55.74 square meters

R 1 = 0.6 for At ≥ 600 square feet (55.74 m ² )

(Equation 16-29)

where: At = Tributary area (span length multiplied by effective

width) in square feet (m ² ) supported by the member, and R 2 = 1 for F ≤ 4 (Equation 16-30)

STRUCTURAL DESIGN

R 2 = 1.2 - 0.05 F for 4 < F < 12 (Equation 16-31)

R 2 = 0.6 for F ≥ 12 (Equation 16-32)

where:

F = For a sloped roof, the number of inches of rise

per foot (for SI: F = 0.12 × slope, with slope expressed as a percentage), or for an arch or dome, the rise-to-span ratio multiplied by 32.

1607.13.3 Occupiable roofs. Areas of roofs that are occupiable, such as vegetative roofs, roof gardens or for assembly or other similar purposes, and marquees are permitted to have their uniformly distributed live loads reduced in accordance with Section 1607.11.

1607.13.3.1 Vegetative and landscaped roofs. The weight of all landscaping materials shall be considered as dead load and shall be computed on the basis of saturation of the soil as determined in accordance with Section 3.1.4 of ASCE 7. The uniform design live load in unoccupied landscaped areas on roofs shall be 20 psf (0.958 kN/m ² ). The uniform design live load for occupied landscaped areas on roofs shall be determined in accordance with Table 1607.1.

1607.13.4 Awnings and canopies. Awnings and canopies shall be designed for uniform live loads as required in Table 1607.1 as well as for snow loads and wind loads as specified in Sections 1608 and 1609.

1607.13.5 Photovoltaic panel systems. Roof structures that provide support for photovoltaic panel systems shall be designed in accordance with Sections 1607.13.5.1 through 1607.13.5.4, as applicable.

1607.13.5.1 Roof live load. Roof structures that support photovoltaic panel systems shall be designed to resist each of the following conditions:

Applicable uniform and concentrated roof loads with the photovoltaic panel system dead loads.

Exception: Roof live loads need not be applied to the area covered by photovoltaic panels where the clear space between the panels and the roof surface is 24 inches (610 mm) or less.

Applicable uniform and concentrated roof loads without the photovoltaic panel system present.

1607.13.5.2 Photovoltaic panels or modules. The structure of a roof that supports solar photovoltaic panels or modules shall be designed to accommodate the full solar photovoltaic panels or modules and ballast dead load, including concentrated loads from support frames in combination with the loads from Section 1607.13.5.1 and other applicable loads. Where applicable, snow drift loads created by the photovoltaic panels or modules shall be included.

1607.13.5.2.1 Photovoltaic panels installed on open grid roof structures. Structures with open grid framing and without a roof deck or sheathing supporting photovoltaic panel systems shall be

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designed to support the uniform and concentrated roof live loads specified in Section 1607.13.5.1, except that the uniform roof live load shall be permitted to be reduced to 12 psf (0.57 kN/m ² ).

1607.13.5.3 Photovoltaic panels or modules installed as an independent structure. Solar photovoltaic panels or modules that are independent structures and do not have accessible/occupied space underneath are not required to accommodate a roof photovoltaic live load, provided that the area under the structure is restricted to keep the public away. Other loads and combinations in accordance with Section 1605 shall be accommodated.

Solar photovoltaic panels or modules that are designed to be the roof, span to structural supports and have accessible/occupied space underneath shall have the panels or modules and all supporting structures designed to support a roof photovoltaic live load, as defined in Section 1607.13.5.1 in combination with other applicable loads. Solar photovoltaic panels or modules in this application are not permitted to be classified as “not accessible” in accordance with Section 1607.13.5.1.

1607.13.5.4 Ballasted photovoltaic panel systems. Roof structures that provide support for ballasted photovoltaic panel systems shall be designed, or analyzed, in accordance with Section 1604.4; checked in accordance with Section 1604.3.6 for deflections; and checked in accordance with Section 1611 for ponding.

1607.14 Crane loads.¶

The crane live load shall be the rated capacity of the crane. Design loads for the runway beams, including connections and support brackets, of moving bridge cranes and monorail cranes shall include the maximum wheel loads of the crane and the vertical impact, lateral and longitudinal forces induced by the moving crane.

1607.14.1 Maximum wheel load. The maximum wheel loads shall be the wheel loads produced by the weight of the bridge, as applicable, plus the sum of the rated capacity and the weight of the trolley with the trolley positioned on its runway at the location where the resulting load effect is maximum.

1607.14.2 Vertical impact force. The maximum wheel loads of the crane shall be increased by the following percentages to determine the induced vertical impact or vibration force:

Monorail cranes (powered) . . . . . . . . . . . . . . . . 25 percent Cab-operated or remotely operated

bridge cranes (powered) . . . . . . . . . . . . . . . . . 25 percent Pendant-operated bridge cranes (powered). . . 10 percent Bridge cranes or monorail cranes with

hand-geared bridge, trolley and hoist . . . . . . . 0 percent

1607.14.3 Lateral force. The lateral force on crane runway beams with electrically powered trolleys shall be calculated as 20 percent of the sum of the rated capacity of

the crane and the weight of the hoist and trolley. The lateral force shall be assumed to act horizontally at the traction surface of a runway beam, in either direction perpendicular to the beam, and shall be distributed with due regard to the lateral stiffness of the runway beam and supporting structure.

1607.14.4 Longitudinal force. The longitudinal force on crane runway beams, except for bridge cranes with handgeared bridges, shall be calculated as 10 percent of the maximum wheel loads of the crane. The longitudinal force shall be assumed to act horizontally at the traction surface of a runway beam, in either direction parallel to the beam.

1607.15 Interior walls and partitions.¶

Interior walls and partitions that exceed 6 feet (1829 mm) in height, including their finish materials, shall have adequate strength and stiffness to resist the loads to which they are subjected but not less than a horizontal load of 5 psf (0.240 kN/m ² ).

1607.15.1 Fabric partitions. Fabric partitions that exceed 6 feet (1829 mm) in height, including their finish materials, shall have adequate strength and stiffness to resist the following load conditions:

The horizontal distributed load need only be applied to the partition framing. The total area used to determine the distributed load shall be the area of the fabric face between the framing members to which the fabric is attached. The total distributed load shall be uniformly applied to such framing members in proportion to the length of each member.
A concentrated load of 40 pounds (0.176 kN) applied to an 8-inch-diameter (203 mm) area [50.3 square inches (32 452 mm ² )] of the fabric face at a height of 54 inches (1372 mm) above the floor.

1607.15.2 Fire walls. In order to meet the structural stability requirements of Section 706.2 where the structure on either side of the wall has collapsed, fire walls and their supports shall be designed to withstand a minimum horizontal allowable stress load of 5 psf (0.240 kN/m ² ).