The scope includes all buildings except detached one- and two-family dwellings and townhouses up to three stories. Previous editions of the IBC have been adopted at the state or local level in all 50 United States plus Washington D.C.
Now in its fifth edition, the 2012 IBC contains many important changes:
- All definitions are included in Chapter 2.
- Classifications for a variety of health-care related facilities have been clarified.
- Covered- and open-mall provisions revised to fully address the construction of open malls.
- Occupancies not specifically scoped under the unlimited area building provisions are now permitted where in compliance as accessory occupancies.
- Clarified provisions for incidental-use rooms and spaces.
- Modified provisions addressing exterior wall projections.
- Reformatted requirements for protection of vertical openings through floors.
- Automatic sprinkler systems required where furniture and mattresses are manufactured or stored.
- Increased capacity for stairways and other egress components in buildings with sprinklers and an emergency communication system.
- Clarification of when unenclosed stairways can be used as a part of the means of egress system, including how travel distance is measured.
- In three- and four-exit buildings, some exits are now permitted to serve a portion of a story rather than an entire story.
- Means of egress provisions unique to special occupancies are now in Chapter 4.
- Wind design requirements extensively revised.
- Wind load maps are now based on ultimate design wind speeds.
- New terminology for wind speeds.
- Updated seismic ground motion maps.
- The term “occupancy category” changed to “risk category.”
- Special inspection requirements for structural steel and masonry construction are now based on referenced standards.
- Penetration firestop and fire-resistant joint systems in high-rise buildings and in Risk Category III or IV structures require special inspection.
- Modifications to the seismic provisions of ACI 318 Appendix D.