What is the required fire rating for walls that are under 5 feet from an adjacent building?

Walls that are located within 5 feet of an adjacent building are required to have a specific fire rating to provide a necessary level of protection against the spread of fire. The International Building Code (IBC) mandates that these walls must be constructed with at least a 1-hour fire-resistance rating. This requirement is established to ensure that if a fire occurs, there is enough time for the occupants to evacuate and for fire services to respond, while also minimizing the risk of fire spreading to the adjacent property.

A 1-hour fire rating signifies that the wall is able to withstand fire exposure for at least 60 minutes, allowing it to serve its intended purpose of fire separation in high-density areas or where adjacent buildings are in close proximity. Although other options such as 2-hour, no fire-rated construction, or 30-minute fire-rated construction do exist within different contexts, they do not apply to this specific scenario where walls are within the critical distance of 5 feet from another building. The code is structured this way to ensure greater safety and alignment with the overarching goals of fire prevention and life safety in residential settings.