10.1 Building Services & Special Construction: Elevators, Membrane, Temporary Structures, Marquees & Signs

1. Elevators and Conveying Systems (IBC Chapter 30)

Chapter 30 is short but generates a steady stream of plan-review corrections because elevator requirements are split among Chapter 30, the shaft and opening-protective rules of Chapter 7, the accessibility rules of Chapter 11 and ICC A117.1, and ASME A17.1/CSA B44.

Hoistway enclosures (IBC 3002):

• Hoistways comply with Sections 712 and 713; where required to be enclosed, the hoistway is a shaft enclosure under Section 713 (3002.1).
• Not more than four elevator cars may be located in a single fire-resistance-rated hoistway, and where four or more cars serve the same portion of a building, they must be in not fewer than two separate hoistways (3002.2).
• Emergency signs are posted at each call station reading IN CASE OF FIRE, ELEVATORS ARE OUT OF SERVICE. USE EXIT, unless the elevator is part of the accessible means of egress or an occupant-evacuation elevator (3002.3).
• Where elevators are provided in buildings four or more stories above or below grade plane, at least one car must accommodate an ambulance stretcher 24 inches by 84 inches with 5-inch radius corners, marked with the star of life at least 3 inches high on both sides of the hoistway door frame (3002.4).
• Elevators may not share a shaft enclosure with a stairway (3002.7), and plumbing and mechanical systems may not be located in the hoistway except floor drains, sumps and sump pumps at the base (3002.9).

Emergency operations (IBC 3003): where standby power is provided, a single elevator must transfer to standby power within 60 seconds of normal power failure, and where two or more elevators share a common operating system, all must transfer within 60 seconds if capacity allows, or transfer in sequence with at least one car remaining operable (3003.1.2, 3003.1.3). Elevators require Phase I recall and Phase II in-car operation per ASME A17.1 (3003.2) and a standardized fire service elevator key (3003.3).

Machine rooms (IBC 3005): machine rooms, control rooms, control spaces and machinery spaces outside the hoistway must be enclosed with fire barriers per Section 707 or horizontal assemblies per Section 711, rated not less than the hoistway they serve, with two exceptions that reduce the rating to 1 hour, or eliminate it in buildings four stories or less, where the spaces do not abut or open into the hoistway. Sprinklered elevator equipment spaces require a shunt trip to disconnect main line power before water is applied (3005.5), and plumbing may not be located in elevator equipment rooms (3005.6).

Elevator lobbies and hoistway door protection (IBC 3006) apply where required by 3006.2, with additional lobby rules for underground buildings (405.4.3), areas of refuge (1009.6.4), fire service access elevators (3007.6) and occupant evacuation elevators (3008.6).

2. Special Construction (IBC Chapter 31)

Membrane structures (3102): the chapter applies to air-supported, air-inflated, membrane-covered cable, membrane-covered frame and tensile membrane structures erected for 180 days or longer; shorter durations fall under the International Fire Code. Tensile membrane and air-supported structures are designed to ASCE 55. Noncombustible membrane structures are classified as Type IIB; heavy timber frame-supported membrane structures are Type IV-HT; others are Type V. Membranes and liners must be noncombustible per 703.3 or pass NFPA 701 Test Method 1 or 2 (3102.3.1). Allowable area follows Section 506 and height follows Section 504.3, generally limited to one story (3102.4, 3102.5). Air-supported structures need auxiliary inflation systems and standby power (3102.8).

Temporary structures (3103): structures erected for less than 180 days. A permit is required for temporary structures covering more than 120 square feet used for the gathering of 10 or more persons (3103.1.3). Construction documents must include a site plan showing means of egress and occupant load (3103.2); location follows Table 705.5 based on exterior wall rating (3103.3); exit access travel distance is limited to 100 feet (3103.4); and temporary bleachers, grandstands and folding and telescopic seating comply with ICC 300 (3103.5). Public-occupancy temporary structures may be extended beyond 180 days up to one year with building official approval and periodic inspections (3103.1.1).

Pedestrian walkways and tunnels (3104): connected buildings are considered separate structures, and the walkway does not contribute to the building area, number of stories or height of the connected buildings (3104.1, 3104.2). Walkways must be of noncombustible construction unless both connected buildings are combustible (3104.3).

Awnings and canopies (3105): designed for wind and live loads per Chapter 16; awning frames must be noncombustible, fire-retardant-treated wood, heavy timber or 1-hour construction; coverings must pass NFPA 701, have a flame spread index not greater than 25 per ASTM E84/UL 723, or meet NFPA 286 criteria.

Marquees (3106): height or thickness is limited to 3 feet where the marquee projects more than two-thirds of the distance from the lot line to the curb line, and 9 feet where it projects less than that; a marquee must be supported entirely from the building, constructed of noncombustible materials, drained so runoff does not spill onto the sidewalk, and located so it does not obstruct standpipes, stairways or exit discharge.

Other Chapter 31 items the examiner routinely checks: signs (3107), telecommunication and broadcast towers designed to TIA 222 (3108), swimming pools and spas under the ISPSC (3109), automatic vehicular gates complying with ASTM F2200 with UL 325 listed openers (3110), and solar energy systems (3111) including rooftop wind resistance, roof live load and fire classification.

Nonstructural component anchorage is easy to miss: rooftop mechanical units, screens, signs, ceilings and cladding must be anchored for seismic and wind forces under IBC Chapter 16 and ASCE 7 Chapter 13, with the seismic special inspection required by Chapter 17 where applicable.

3. Plan Review Scenario: Mixed Building Services Package

Submittal: a six-story Type IIA Group B office building with four elevators in a single hoistway, a rooftop elevator machine room, an enclosed pedestrian walkway to a neighboring parking structure, a 4-foot-thick marquee projecting three-quarters of the way to the curb, and a 3,000-square-foot air-supported tensile membrane structure for a seasonal event lasting eight months.

Examiner findings:

1. Hoistway grouping violation. Four cars serving the same portion of the building must be split into not fewer than two hoistways, with a maximum of four cars in any single hoistway (3002.2).
2. Machine room rating. The rooftop machine room must be enclosed with fire barriers or horizontal assemblies rated not less than the hoistway enclosure, unless it qualifies for one of the two exceptions in 3005.4.
3. Stretcher car. With six stories above grade plane, at least one car must accommodate a 24-inch by 84-inch ambulance stretcher and carry the star-of-life marking (3002.4).
4. Walkway area. The pedestrian walkway does not add to building area or story count, and both buildings remain separate structures (3104.2); confirm the walkway is noncombustible (3104.3).
5. Marquee thickness. Projecting more than two-thirds of the distance to the curb limits the marquee to 3 feet in height or thickness; the 4-foot design fails 3106.2.
6. Membrane structure duration. Eight months exceeds 180 days, so the structure is regulated as a membrane structure under 3102, not a temporary structure, and must be classified by construction type with NFPA 701 membrane documentation and a standby-power inflation system.

4. Common Plan Review and Exam Traps

• Trap 1: The 180-day line. Under 180 days is a temporary structure (3103); 180 days or more is a membrane structure (3102) or permanent construction.
• Trap 2: Counting the walkway. Pedestrian walkways do not add area, stories or height.
• Trap 3: Elevators sharing stair shafts. Prohibited by 3002.7 except within open parking garages.
• Trap 4: Assuming standby power means instant transfer. The code allows up to 60 seconds and permits sequenced transfer for multiple cars.
• Trap 5: Missing the marquee geometry rule. The 3-foot versus 9-foot limit turns on the two-thirds lot-line-to-curb projection test.