What kind of walls extend from the floor to the underside of the floor above?

Fire barrier walls are designed to prevent the spread of fire and are constructed to extend from the floor to the underside of the floor above. This full vertical extension is essential for creating a fire-resistance rating that effectively contains a fire within a designated area, allowing for safer evacuation and protecting structural integrity.

Fire barriers are typically used in commercial buildings and multi-family residential constructions where specific compartments are required to limit the spread of flames and smoke. Their construction and design adhere to building codes that specify the necessary fire-resistance ratings based on the building's use and occupancy type.

In contrast, load-bearing walls provide structural support to the building and do not necessarily have fire-resistant characteristics, while nonbearing walls simply serve as partitions without carrying any load. Curtain walls, on the other hand, are exterior walls that do not support the structure and primarily serve as a weather barrier, lacking the fire-resistance functions that fire barrier walls provide.