Reliable roof drainage is essential for protecting commercial and institutional buildings from costly water damage. The Zurn RD2120 Main Area Roof Drain is specifically engineered for large flat or low-slope roofs, offering dependable performance and watertight integration with modern roofing systems. In this blog, we’ll explore its features, applications, installation guidelines, and include a real-world case study.

Zurn RD2120 Roof Drain Schematic

What Is the Zurn RD2120?

The RD2120 is a main area roof drain designed for large roof structures where high-capacity drainage is critical. It integrates seamlessly with roofing membranes, ensuring a watertight seal while efficiently directing stormwater into piping systems. With a durable dome strainer and robust bowl construction, the RD2120 helps prevent clogging and ensures consistent flow even during peak rainfall events.

Key Features & Benefits

• High-Capacity Drainage: Engineered to handle large volumes of stormwater from expansive roof areas.
• Dome Strainer: Prevents debris entry while maintaining maximum intake capacity.
• Watertight Integration: Flashing clamp ensures a secure bond with roofing membranes.
• Durable Construction: Built with long-lasting materials for reliability in harsh rooftop environments.
• Versatile Use: Suitable for a wide range of commercial and institutional roofing applications.

Zurn Brand Quality

Applications of the RD2120

• Commercial office buildings with flat roofing
• Industrial facilities with large roof spans
• Institutional campuses such as schools and hospitals
• Warehouses and distribution centers

Installation Best Practices

To ensure optimal performance, the RD2120 should be installed following these best practices:

• Install drains at natural roof low points to capture maximum stormwater.
• Use the flashing clamp to create a watertight seal with roofing membranes.
• Verify outlet pipe sizing aligns with hydraulic flow calculations.
• Perform seasonal inspections to remove debris and check dome strainer integrity.
• Water-test after installation to confirm proper drainage function.

Case Study: Commercial Office Tower

Challenge: A downtown office tower experienced roof ponding and membrane stress due to undersized drains that could not handle peak rainfall.

Solution: Engineers specified Zurn RD2120 Roof Drains for the main roof areas. The high-capacity design and secure flashing clamp system ensured efficient drainage and watertight integration.

Outcome: The tower now experiences consistent stormwater management even during heavy downpours. Maintenance calls dropped significantly, and roof warranties were preserved due to the improved drainage system.

Conclusion

The Zurn RD2120 Main Area Roof Drain is a reliable and high-performing solution for large commercial and institutional roofs. With its durable construction, watertight integration, and high-capacity design, it delivers peace of mind and long-term protection for building owners and facility managers.