What is a defining characteristic of Type III construction?

Type III construction, also known as ordinary construction, is characterized by a combination of non-combustible exterior walls and combustible interior structural elements. This type of construction often uses masonry for the exterior, while the interior can consist of wooden beams and other combustible materials. The defining feature is the presence of these combustible interior structural members, which significantly affects fire behavior and safety considerations.

This construction type frequently has hidden spaces within the walls or ceilings where fire can spread undetected, increasing the risk in the event of a fire. The specification of partially wooden interior structural elements is essential to differentiate Type III from both non-combustible types and those that rely solely on combustible materials. Consequently, understanding this aspect is crucial for fire safety practices and building regulations.