C. *Type A construction is the most fire-resistant, Type C building is the least fire-resistant, and Type B construction is somewhere in the middle. Page 2According to the DTS Provisions, buildings of Type A and B construction must have a fire resistance rating of at least 10 hours while those of Type C must be rated at least 6 hours.
Fire-resistant building codes were first developed in the United States during the 1920s when large numbers of people were dying in fires each year. The codes were adopted by most cities and states across the country and are still in use today. They require property owners to protect their buildings by making them fire resistant. Fire walls, fire doors, fire escapes, and sprinkler systems are all required by law in fire-resistant buildings.
The code defines three types of fire resistance: Type A, B, and C. Type A buildings are completely enclosed structures with no open windows or doors. They are used for storage of highly flammable materials such as gasoline or chemicals. These buildings must be constructed of type-specified material and meet the requirements of both the DTS and local building codes. Type B buildings have certain openings (such as window and door frames) that cannot be closed off by fireproofing measures. They are used for storing less hazardous materials such as paper, wood, and plastic.
C. C. * Type A construction is the most fire-resistant, Type C construction is the least fire-resistant, and Type D construction is the least fire-resistant. The type of construction used in a building determines what fire protection it will get from the building code.
Type A buildings have protected walls and protected floors with no open airings over 30 ft. high. They are the most fire-resistant but also the most expensive to build.
They are less fire-resistant than Type A buildings but cheaper to build.
Type C buildings have unprotected walls and protected floors with no open airings over 30 ft. high. They are the least fire-resistant but also the cheapest to build.
Type D buildings have unprotected walls and floors with some open airings over 30 ft. high.
Fire resistance ratings range from Type 1 to Type 10. The higher the number, the more resistant the material or component is to fire. Fireproofing materials used in construction include brick, block, concrete, steel, and glass.
To account for the reaction that a structure will have to a fire that arises within the building as a result of the occupancy it serves, it is critical to appropriately identify a building by its type of construction. Every building must be classed as one of five different styles of construction, according to the building code. These are frame, brick, block, panel, and concrete. A building can be any combination of these styles. For example, a frame house with vinyl siding and a concrete foundation is considered a frame house.
The classification system is based on how the building is constructed. If you look at a typical house, it is mostly made up of frame elements: beams, columns, and roofs. The parts of the house that touch the ground are called foundations. The term "structure" is used to describe the entire building, including the foundation.
Frame buildings are the most common type of construction in the United States. They are easy to build and inexpensive to rent or own. A frame building has horizontal members (beams) that support the vertical members (columns) which in turn support the roof. The size of the frame is determined by the weight it needs to bear and the distance it needs to span. At the bottom of each frame member there should be a gap where the end grain of the wood meets. This is called an "end nailing slot" and it is required by law in some states to provide fire protection.
Class B structures have reinforced concrete frames, concrete or masonry floors, and masonry roofs. The reinforced concrete frame, in which the columns and beams can be built or prefabricated, is the major feature of a Class B structure. Mechanical tension may be applied to them. It is a fire-resistant building. Fireproofing in Class B buildings should be at least 10 minutes in duration for vertical walls and ceilings and 20 minutes for horizontal floor joists and roof trusses.
Class B construction is used primarily for commercial buildings and industrial facilities. It is very strong and can support heavy loads. The roof is the only part that cannot be made of combustible material because it acts as an outer wall for the building.
The roof is the main source of heat in a class B building during hot weather. The heat can cause materials such as paint and wood finishes to dry out and crack. Cooler air from outside the building is drawn into the building through the open roof area. As this happens, the temperature inside the building decreases. Energy efficient design is important in class B buildings because they use a lot of energy.
Class B buildings do not require as much structural reinforcement as class A buildings due to their heavier duty construction. However, even class B buildings need some form of internal reinforcement.