There is no doubt that fire sprinklers provide protection to both buildings and their occupants. However, when working on projects involving existing buildings that do not have fire sprinkler protection systems, or where the available water service is inadequate to support the installation of such systems without adding a storage tank and pump, we may need to explore other paths to compliance.
The International Building Code (IBC) sets thresholds for certain occupancies regarding the requirement for fire sprinklers, based on factors such as the size of the fire area, occupant load, and location of the space. Thus, it is possible to create fire areas with less square footage and lower occupant loads than the thresholds that trigger the requirement for fire sprinkler systems.
On a project involving an existing church and its associated school, it was proposed to enclose the space between the two existing buildings, thereby creating one large mixed-use building that complied with the allowable height and area requirements. However, the occupant load for the worship space, classified as A-3 occupancy, would exceed the allowable limits, necessitating the installation of sprinklers. The costs associated with the retrofit installation and the addition of a storage tank and fire pump were not accounted for in the project budget.
The design professional revised the plans to include fire barriers to create smaller fire areas, thereby lowering the occupant loads within the fire areas to meet the IBC requirements. When the plan reviewer conducted their review of the revised plans, they stated that the fire barriers were inadequate and that the separation assemblies needed to be fire walls. This is a common misconception, but the code establishes criteria for both firewalls and fire barriers.
In general, fire walls are used to create separate buildings and ensure compliance with building height and area requirements. However, there are specific instances where the code may require the use of fire walls. Fire walls must be constructed to withstand the collapse of structures on either side without collapsing themselves under fire conditions. In contrast, fire barriers are used to create separate fire areas, separate occupancies when required and provide protection for specific means of egress elements. Fire barriers do not have the same structural integrity requirements as fire walls. After presenting this information to the plan reviewer and allowing them time to digest it, it was determined that the plans were compliant.
Generally, everyone wants to do their job correctly and in a compliant manner. Sometimes, we just need to ensure that we present information in the appropriate format.This applies to all parties involved in the process.
References: The following code references can be found in the 2021 International Building Code as printed by the International Code Council: Sections 503.1, 707.3.10, and 901.7.
