What is a discontinuous roofing system?

• A. A system with unsealed overlapping components
• B. A system with continuous seams
• C. A system with sealed joints
• D. A system without flashing

Answer: (A)

Discontinuous roofing means the joints where pieces meet are not sealed, so the overlaps between components do not form a continuous waterproof barrier. Water can find its way through gaps where pieces just meet without being sealed along the full length. This is different from a system with continuous seams or sealed joints, which create an uninterrupted moisture barrier. A system with sealed joints describes the continuous, locked-together sealing you’d expect in a properly weatherproofed roof. Simply lacking flashing is a separate concern; flashing helps direct water but doesn’t by itself determine whether overlaps are sealed or not. The defining idea here is the unsealed overlapping components that break the continuity of the waterproof layer.