Which of the following is a live load on a roof?

• A. Roofers and other personnel
• B. Structural membranes and other fixed loads
• C. Snow
• D. Wind

Answer: (A)

Live loads are temporary, movable loads that can be removed, such as people on the roof or equipment being used there. Roofers and other personnel on the roof fit that description because their presence is not permanent and can change from one moment to the next. Structural membranes and other fixed loads are dead loads—the permanent weight of the roof itself and its components. Snow and wind come from weather and act as environmental loads; they’re not considered live loads in this context even though they affect the roof design, and they’re treated separately as snow load and wind load.