Watts - GRD-640 - Green Roof Metered Overflow Drain Tactile Paving corrosion-resistant ductile iron ensures lasting

corrosion-resistant ductile iron ensures lasting performance

or protective coverings

A durable alternative to concrete drains

heavy grates

This design aligns with research from the University of California Statewide Integrated Pest Management Program

Watts - GRD-640 - Green Roof Metered Overflow Drain Tactile Paving corrosion-resistant ductile iron ensures lastingThe Watts GRD 640 is a stainless steel metered overflow drain designed for green roof and planter applications where controlled secondary drainage is required. Its epoxy coated cast iron body provides long term durability, while the perforated stainless steel gravel guard with secured solid cover helps prevent debris and ballast intrusion. The ABS standpipe includes a 5 8 inch orifice to regulate overflow, and the drain comes standard with a no hub