The Watts RD-500 is a large-area roof drain engineered for commercial and industrial roof systems requiring high-volume primary drainage. Its epoxy-coated cast iron body provides strong corrosion resistance, while the flashing clamp and integral gravel stop ensure a secure, watertight membrane attachment. A self-locking polyethylene dome helps protect the drain from debris intrusion, and the unit includes a standard no-hub outlet for straightforward installation.

Key Features

• Epoxy-coated cast iron body for durability and corrosion resistance

• Flashing clamp with integral gravel stop for secure membrane integration

• Self-locking polyethylene dome for debris protection

• Standard no-hub outlet for easy connection

• Ideal for large-area primary roof drainage applications