Drains carry water through the roof, scuppers carry it through a wall, and gutters collect it at an edge. The best arrangement depends on roof geometry, outlet capacity, overflow provisions, and maintenance access.

What to check first

  • Trace both the normal drainage route and the overflow route.
  • Consider how leaves and debris will be removed safely.
  • Have changes in outlet size or location designed for the building rather than selected by appearance.

Separate a leak from a drainage problem

  1. Trace the water route

    Follow water from the roof surface through the inlet and toward the discharge point. Inspect normal drainage and any separate overflow provision.

  2. Check the waterproof connection

    A sound pipe does not prove the membrane-to-drain connection is sound. Look for loose components, separation, damaged flashing, or patch buildup around the inlet.

  3. Preserve the opening

    A compatible local repair must not reduce the effective outlet or cover its strainer. Persistent ponding, backup, or changes to drain location and size need building-specific professional assessment.

From the project archive

Pros and Cons of Drains, scuppers and gutters
Historical project photo · Flat Roof Doctor
The position of Internal drains are crucial and should be located where water ponding occurs
Historical project photo · Flat Roof Doctor
Gutters on flat roofs need maintenance - leaves constantly fill gutters up
Historical project photo · Flat Roof Doctor

Product reference: Bergstrom Industries’ published knowledge catalog. Follow the latest product label and safety information. Historical project examples are educational and are not a specification for every roof.