Which construction type is described as having masonry exterior walls and is typical for commercial buildings?

The correct answer is Type 3 Construction. This type is characterized by having exterior walls that are made of non-combustible materials, such as masonry, while the interior structure can be composed of wood or other combustible materials. This construction style is commonly used for commercial buildings because it balances fire resistance from the exterior walls with lower costs associated with wood framing for the internal structure.

Type 3 Construction is often seen in buildings such as warehouses, schools, and some retail spaces, where durability and fire safety are of utmost importance while still allowing for efficiency in building practices. The use of masonry for exterior walls not only provides structural integrity but also enhances fire resistance, making it ideal for areas with high foot traffic and occupancy.

Types 1 and 2, on the other hand, involve more extensive use of non-combustible materials throughout the entire structure, often resulting in taller buildings. Type 5 is characterized by a frame structure that is primarily made of wood, which is less applicable to commercial settings where fire safety and durability are critical. Thus, Type 3 is the most fitting description for buildings that have masonry exteriors while allowing for the interior wood elements used in commercial construction.