Which of the following materials can be used for draftstopping floors?

Draftstopping is critical in commercial buildings to prevent the spread of smoke and fire through concealed spaces, particularly in floors and ceilings. The materials used for draftstopping must meet specific requirements to ensure they can effectively limit the flow of air, smoke, and heat.

Gypsum board, such as 1/2" thickness, is commonly used as it provides a non-combustible barrier that can withstand heat and help contain fire. It also has a degree of sound attenuation, which is beneficial for both fire and noise control in multi-tenant buildings.

Wood structural panels, like 3/8" thickness, are also acceptable for draftstopping. They can effectively create a barrier against drafts and air movement, especially when properly installed and sealed. When treated or installed certain ways, these panels can also contribute to the overall fire resistance in a building.

Similarly, 1" nominal lumber can be used as it can provide sufficient mass and structure to serve as a barrier against fire and smoke. The thickness and type of lumber ensure it can fulfill the requirements set by building codes regarding fire safety and draftstopping.

Thus, because all three material options meet the necessary criteria for use as draftstopping in floors, the answer encompasses all of them