Roofing Glossary

Scupper

A scupper is an opening cut through a parapet wall (or the edge of a flat roof) that lets water drain off — the flat-roof equivalent of a gutter outlet. Water flows across the roof, through the scupper, and into a downspout or off the building.

Scuppers are simple and reliable, with no moving parts and nothing to clog below the roofline — but the openings themselves do clog with leaves and debris, which is why they need regular clearing. Many codes also require overflow scuppers set slightly higher as emergency backup: if the primary drainage blocks, water exits through the overflow before the roof's weight limit is threatened.

Scupper boxes, often with decorative faces, collect water at the opening and direct it into the downspout. Their flashing into the roof membrane is a critical waterproofing detail.

Why It Matters

On flat roofs, drainage is life. Clogged scuppers are the most common cause of flat-roof ponding — and clearing them is basic maintenance, not a roofing project.

What to Watch For

• Debris packed into scupper openings
• Staining on the wall below a scupper (overflow pattern)
• No visible overflow scupper on a parapet flat roof

Questions about your own roof? Request a free estimate or call Nucci Brothers Roofing at (301) 458-1003.