What are parapet walls?

Parapet walls are architectural features that extend above the roofline, typically found on flat or low-slope roofs. They serve a variety of purposes, such as providing a barrier for safety to prevent people from falling off the roof, helping to protect the building from fire, and adding aesthetic appeal to the structure's appearance.

Additionally, they can be important in terms of drainage and water management, preventing water from running off the roof and onto the sides of the building, which could lead to structural issues over time.

Understanding the role of parapet walls is crucial for firefighters when assessing buildings during incidents, as these walls can impact the way fire spreads and can influence tactics used during firefighting operations. The other options provided do not accurately define parapet walls, highlighting their specific function of extending above the roofline rather than other aspects of construction or safety features.