![Roofing Drainage Systems [AIA course]](/sites/default/files/February%202019%20Roof%20Drainage%20AIA%20course.jpg "Roofing Drainage Systems [AIA course]")
Among the most fundamental of architectural elements is the roof. Its principal purpose is to shelter a building’s occupants, contents, and structure from the elements, most critically from precipitation.
While the various layers of the roof assembly play a key role in keeping moisture from infiltrating into the interior, adequate weather protection also depends on the roof’s ability to drain moisture away from the building. If rainwater, snow, and ice accumulate, the moisture can degrade and permeate the roofing assembly.
Not only does standing water negatively impact the performance, integrity, and longevity of the building enclosure, but it also can deteriorate the structural and interior elements the building enclosure is meant to protect.
LEARNING OBJECTIVES
After reading this article, you should be able to:
• Distinguish among various types of low- and steep-slope drainage assemblies and identify design considerations for each system.
• Identify the components of Protected Roof Membrane Assemblies (PRMA), vegetative roofs, and traditional roofs.
• Recognize signs of distress or potential problems and trace the issue to the primary design or installation shortcoming.
• Prepare a schedule of routine maintenance and repair that can proactively identify emerging problems.
