Key nonstructural changes to 2012 IBC
The new 2012 International Building Code (IBC) was published June 9, 2011, and is being adopted as the applicable building code by many states, counties, cities, and municipalities across the United States. As part of the triennial code development process, the 2012 IBC includes many new or revised code requirements not previously included in the 2009 IBC.
While it is important for the members of a design or building assessment team to understand the impact of building code changes on all the members of the team, this article focuses on the significant nonstructural changes to the 2012 IBC that typically impact consulting and specifying engineers, other than structural and material requirements. Separate articles would be necessary to discuss the changes to the structural/material requirements and changes that primarily impact the practice of architecture. For a more complete discussion of these changes in the 2012 edition of the IBC, one can refer to Significant Changes to the International Building Code, 2012 Edition, published by the International Code Council (ICC).
Fire service access elevators: Paragraph 403.6.1 has been revised to require a minimum of two fire service access elevators in buildings with an occupied floor level more than 120 ft above the lowest level of fire department vehicle access. The 2009 IBC required only one fire service access elevator. In addition, the paragraph now includes a requirement that each elevator have a capacity of at least 3,500 pounds. Under normal conditions, the revision results in at least two elevators being available for fire suppression personnel in such buildings. In addition, because an elevator may be out of service, the change results in a reasonable expectation that at least one fire service access elevator will be available at all times.
It should be noted that there have also been revisions to the detailed requirements for fire service access elevators and occupant evacuation elevators. For the most part, these revisions provide for the elevators to be able to continue to function and serve their intended purpose during an emergency (Sections 3007 and 3008, respectively). A complication unresolved in the 2012 IBC is related to the requirement for direct access between the fire service access elevators and the exit stair enclosure. This complication will likely be resolved in the 2015 IBC. Users of the code should consider reviewing the changes in the 2015 edition for potentially more reasonable design direction. Use of the 2015 language should be reviewed with the authorities having jurisdiction (AHJ).
Fire ratings of exterior walls: A new note “h” has been added to Table 602 to clarify that nonrated exterior walls are permitted when nonbearing exterior walls with unlimited openings are permitted by Table 705.8. This occurs when the building is protected with automatic sprinkler protection and the fire separation distance is at least 20 ft.
Using sprinklers to achieve a fire resistance rating: In the past there has been an ICC-ES Evaluation Report (ESR-2397) that describes a glass assembly protected with a specific automatic sprinkler as having a fire resistance rating of 2 hours. The 2012 IBC contains Section 703.4, which restricts the use of automatic sprinklers or any other fire suppression system when testing an assembly to achieve a fire resistance rating. When installing a sprinkler in the furnace, the tested assembly is not likely to be exposed to the standard temperature-time curve as required by the fire test because operation of the sprinkler will result in a cooling effect within the furnace. As such, the fire test would not be in strict compliance with the required fire test standard. That is not so say that an assembly that is protected with a specific sprinkler or specific sprinkler design may not be considered to be equivalent to a fire-rated building element or assembly, but rather that the sprinkler may not be part of the fire test used to qualify the building element or assembly. The IBC commentary on this code change clarifies that it is not the intent of the code to prohibit the use of such sprinklers. Rather, the change implies that the use of a window sprinkler system to provide such rating is to be considered under alternate materials and methods of construction. Therefore, such window sprinklers remain a viable candidate for the right applications.
Refuse and laundry chutes: Section 713.13 contains a provision to require the use of NFPA 82: Standard on Incinerators and Waste and Linen Handling Systems and Equipment, Chapter 5, for determining the requirements for refuse and laundry chutes in buildings of Group I-2. It should be noted that the 2015 IBC will require the use of NFPA 82 for refuse and laundry chutes in all occupancies (FS60-12).
Elevator lobbies: Elevators that only serve lower levels of a high-rise building (less than 75 ft above the lowest level of fire department access) need not have elevator lobbies since those elevator shafts should not experience the same pressure difference as the shafts serving the upper floors (Exception No. 4.3, Paragraph 713.14.1)
Floor penetrations: Historically the IBC has not required a T rating for through penetration firestop systems when the floor penetration was contained and located within the cavity of a wall. The 2012 IBC has extended this exemption for the T rating to include floor penetrations for floor drains, tub drains, and shower drains contained and located within a concealed space of a horizontal assembly (Exception No. 2, Paragraph 7188.8.131.52.2). As with a wall cavity, the provision assumes that a T rating is not required due to the reduced likelihood that combustibles will be exposed to any temperature increase of the penetrating item.
Duct penetrations of fire partitions: A new exception has been added to permit the omission of fire dampers where a ducted HVAC system penetrates a fire partition having a fire resistance rating of 1 hour or less and located in a building protected throughout with an automatic sprinkler system. The exception clarifies what is intended by a “ducted HVAC system,” and the provision is the same as what was previously permitted for duct penetrations of 1-hour fire barriers (Exception No. 4, Paragraph 717.5.4).
Sprinklers in ambulatory care facilities: Recognizing that ambulatory care facilities are often located in office buildings in which the fire resistance rating of the floor may not be adequate to define a separate fire area, Paragraph 903.2.2 has been revised to require automatic sprinkler protection throughout the entire floor containing an ambulatory care facility, all floors below the ambulatory care facility, and all floors between the ambulatory care facility and the level of exit discharge. However, if there are floors above the ambulatory care facility, they need not be protected with an automatic sprinkler system even if the fire resistance rating of the floor is less than what is required to separate fire areas.
Manufacture, display, and storage of upholstered furniture and mattresses: The threshold for mandating sprinkler protection in Groups F-1 and S-1 has been revised to include a requirement for sprinkler protection if upholstered furniture or mattresses are manufactured or stored and the area exceeds 2,500 sq ft. In addition, the existing requirement for sprinkler protection in Group M occupancies used for the display and sale of upholstered furniture in excess of 5,000 sq ft has been expanded to include the display and sale of mattresses (Paragraphs 903.2.4, 903.2.7, and 903.2.9).
Emergency voice/alarm communication captions: In stadiums, arenas, and grandstands, the emergency voice/alarm communication system shall include the ability to display captions where audible public announcements are also required to include captions by Paragraph 1184.108.40.206 (Paragraph 907.5.2.2.4).
Voice alarm systems in schools: The fire alarm system in Group E occupancies shall now include an emergency voice/alarm communication system. In addition, the threshold for when a fire alarm system is required in a Group E occupancy has been reduced to an occupant load of more than 30 (previously it was 50 or more) (Paragraph 907.2.3). As noted below, where automatic sprinkler protection and emergency voice/alarm communication systems are provided, lower egress capacity factors may be used.
College and university residential buildings: Where there is an interior corridor serving sleeping rooms, college and university buildings containing a Group R-2 occupancy are required to have an automatic smoke detection system in the corridors, common spaces, laundry rooms, mechanical equipment rooms, and storage rooms. In addition, the smoke alarms in Group R-2 college and university buildings are required to be interconnected with the building fire alarm system (Paragraph 907.2.9.3).
Carbon monoxide detection: A new section (908.7) has been added to require carbon monoxide alarms or carbon monoxide detection systems in Group I and Group R occupancies where the building contains fuel-burning appliances or an attached garage.
Egress capacity factors: Where automatic sprinkler protection and emergency voice/alarm communication systems are installed in other than Group H and I-2 occupancies, a reduced egress capacity shall be permitted to be used (Section 1005.3).
Floor-level exit signs: Where exit signs are required in Group R-1 occupancies, additional low-level exit signs shall be provided in all areas serving guest rooms. In addition to increasing the level of safety for the building occupants, the substantiation also noted that such signs will also increase firefighter safety (Section 1011.2).
Attic ventilation: The 2012 Edition of the IBC provides for reduction in the vent area for attics; when determined to not be necessary by the building official, attic ventilation shall not be required (Section 1203.2).
Photovoltaic systems: New provisions have been added for photovoltaic elements (modules/shingles or systems) including requirements to meet the existing requirements for roofing materials and rooftop structures (Sections 1505.8, 1507.17, 1509.7, and 3111).
Special inspections: A new requirement for special inspections of through penetration firestop systems and fire-resistant joint systems has been added for high-rise buildings and for buildings assigned a Risk Category III or IV in accordance with Section 1604.5. The special inspections are to be conducted in accordance with ASTM E2174 or ASTM E2393 (Section 1705.16).
In addition to the above items, registered design professionals should review the 2012 Edition of the IBC in its entirety to identify all the proposed changes that may impact their practice of engineering.
William E. Koffel is president of Koffel Associates Inc. He has been an active participant in the International Code Council process since the inception of the ICC, serving on numerous committees and currently serving on the ICC Code Technology Committee. He was the 2010 recipient of the ICC Affiliate Award.