In fire construction classifications, what does Type 3 require for exterior walls?

Type 3 construction, also known as "Ordinary Construction," requires exterior walls to be composed of non-combustible materials. This classification is designed to enhance fire resistance while allowing for a degree of combustible materials in other parts of the structure, like floors or roofs. The use of non-combustible materials for the exterior walls minimizes the risk of ignition and helps contain potential fires within the structure. This is crucial for preventing the spread of fire to adjacent buildings and ensuring the overall safety of the construction.

In Type 3 construction, while the exterior walls are primarily non-combustible, the interior elements can include materials that may be more susceptible to fire, but these elements must still meet specific fire-resistant rating criteria. This construction type is often seen in commercial and mixed-use buildings because it balances safety and cost-effectiveness tightly.

Choosing the option indicating non-combustible materials aligns with building codes and safety standards for this type of construction, underscoring its importance in fire prevention and control.