Change Type:


Change Summary:

Open parking garages are required to be equipped with an automatic sprinkler system when the fire area exceeds 48,000 square feet.

2021 Code Text:

903.2.10 Group S-2 enclosed parking garages.

An automatic sprinkler system shall be provided throughout buildings classified as enclosed parking garages in accordance with Section 406.6 where either where any of the following conditions exist:

  1. Where the fire area of the enclosed parking garage, in accordance with Section 406.6 of the International Building Code, exceeds 12,000 square feet.
  2. Where the enclosed parking garage, in accordance with Section 406.6 of the International Building Code is located beneath other groups.
  3. Exception: Enclosed parking garages located beneath Group R-3 occupancies.
  4. Where the fire area of the open parking garage in accordance with Section 406.5 of the International Building Code exceeds 48,000 square feet.

903.2.11.3 Buildings 55 feet or more in height.

An automatic sprinkler system shall be installed throughout buildings that have one or more stories with an occupant load of 30 or more located 55 feet or more above the lowest level of fire department vehicle access, measured to the finished floor.

Exceptions: Exception:

  1. Open parking structures.
  2. Occupancies in Group F-2.

Change Significance:

Historically, open parking garages have been considered to have a very low fire risk, which has led to dozens of special allowances for reduced code requirements in these occupancies. Fire tests run decades ago offered support for this perspective. However, it is common knowledge that many components of vehicles currently manufactured are combustible. Many of the body and interior components that previously have been steel are now plastic, rubber, fiberglass and lightweight metals. The new methods of vehicle construction facilitate vehicle-to-vehicle fire spread and production of dense combustible smoke layers. Stored energy systems in electric vehicles also increase the fuel load. Nevertheless, the wisdom of exempting open parking garages from many code requirements that would otherwise apply has largely gone unchallenged, lacking sufficient evidence to demonstrate the existence of a problem.

An open parking garage fire in Liverpool, UK on January 1, 2018 demonstrated the fire risk associated with the new methods of vehicle construction. The concrete building and 1,400 cars were destroyed by a fire that reportedly started in a single vehicle’s engine compartment. The concept of fire risk mitigation by allowing heat and smoke to escape through the open perimeter of an open parking garage has been debunked by this incident.

This revision acknowledges that these structures and their contents can present significant fire challenges and result in catastrophic fire losses. The requirement for fire sprinklers in enclosed parking garages remains for fire areas exceeding 12,000 square feet. This new requirement for open parking garages is added and requires fire sprinklers when the fire area exceeds 48,000 square feet. This threshold is four times the threshold applicable to enclosed garages, recognizing that, while there may be some benefit to perimeter openings, the fire service will ultimately be relied on to control these fires if sprinklers are not provided.

An open parking garage will typically consist of one fire area. To create multiple fire areas, IBC Table 707.3.10 requires 2-hour fire-resistance-rated construction.

Section 903.2.11.3 is revised by deleting the exception that eliminated the need to install fire sprinklers when an open parking garage exceeds 55 feet in height. This correlates with the requirement for fire sprinklers in open parking garages in Section 903.2.10, Item 3.