Describe two ways to drain roof water.

Question

What will be an ideal response?

Answer 1

Flat roofs and other such surfaces usually slope toward interior roof drains. The roof drains are raised cast iron, plastic, or aluminum strainers set in the center of a sloped area. Water drains through downpipes, which may be hidden internally or mounted on the exterior of a building. The downpipes connect to a storm drain below the building, which connects to the storm sewer outside the building. Another technique is to slope the roof toward scuppers, which provide outlets in the parapet wall and drain the surface water through them into downpipes and on to the storm sewer.