Which construction type is characterized by heavy timbers?

The construction type characterized by heavy timbers is recognized as Type IV construction. This classification is commonly referred to as "Heavy Timber" construction.

In Type IV construction, the structural framework is made up of solid timber members, which can significantly enhance the stability and load-bearing capacity of the building. The use of heavy timbers is not only a structural choice but also provides a unique aesthetic quality that is often sought after in various architectural designs.

Additionally, Type IV buildings benefit from the fire-resistant properties of heavy timber; although wood does burn, large timber members can withstand fire for a considerable duration due to their size. The slow charring rate of heavy timbers allows for critical structural integrity to be maintained during a fire incident, providing more time for evacuation and safety.

This classification is distinct from other types, such as Type I and Type II, which rely on non-combustible materials like concrete and steel, and Type III, which typically uses a combination of wood frame and non-combustible exterior walls. Each type has specific regulations and standards for safety and construction methods, but Type IV stands out specifically due to its heavy timber characteristics.