Which construction type typically has exterior walls of masonry and wooden interior walls?

Type 4 construction, also known as "Heavy Timber" construction, is characterized by exterior walls made of masonry materials such as brick or concrete, combined with interior walls that are typically constructed of heavy timber or wood. This method provides a strong structure while also allowing for some degree of fire resistance due to the mass and material properties of the exterior masonry walls.

In Type 4 construction, the use of heavy timber for the interior provides good structural strength and fire resistance, while the masonry exterior protects against weather and adds additional fire resistance. The combination of these materials results in a more durable building that can also efficiently handle certain types of fire loads, making it a distinctive construction type compared to others that rely solely on wood or lighter materials.

Other construction types vary in their primary materials and structural characteristics, which affect their fire behavior and vulnerability. For example, Type 3 construction primarily features wood framing enclosed with any material that can include lighter wood or non-combustible materials, but it does not specifically have the heavy timber aspect. Type 2 construction involves non-combustible or limited-combustible materials but typically lacks the heavy timber feature that distinguishes Type 4. Type 5 construction consists mainly of combustible materials with a focus on lightweight