The building codes of the country have established a system of classification that categorizes the different types of buildings. These categories are based on various factors including design, height, usage and safety. However, these categories do not define the specific types of materials used in the construction. Nonetheless, these categories provide the basic standards for fire resistance of buildings.
Buildings classified as Type IV are heavy timber structures. To be categorized as such, the structural wood support must be at least 8 inches thick and the exterior walls must be constructed with non-combustible materials. They are also required to have heavy planks six inches thick.
Aside from requiring the use of heavy timber and non-combustible material, these structures also require water to extinguish fires. Firefighters also must ventilate the buildings to avoid a dangerous rise in temperature. This is done through roll-outdoors and other methods.
Wood-framed buildings are the most combustible type of buildings. Their roofs and interior walls are flammable. However, the roofs can be constructed of lightweight concrete. Alternatively, they can be made of metal.
Firefighters must be concerned about the safety of Type V buildings. These structures do not offer any fire protection. When a fire starts, the fire will spread quickly through the horizontal void spaces. Moreover, the collapse of these structures can happen easily.
The type of construction has a significant impact on the safety of occupants in case of fire. It is also a factor in determining the exit placements, square footage, window and door openings, and sprinkler placement.