The Zurn RD2130 is a compact, heavy-duty combination roof drain and overflow designed to manage routine rainfall and protect the roof during extreme events—within one integrated assembly. This guide explains how the RD2130 works, where it excels, what to consider during installation, and how it performs in the field.

Zurn RD2130 — Combination Roof Drain & Overflow

What Is the Zurn RD2130?

The RD2130 is a cast-iron combination roof drain with an integrated overflow pathway. By pairing a primary drain with an overflow in one body, the unit simplifies layouts, reduces penetrations, and helps designers meet code-mandated overflow requirements without separate devices. Its rugged construction, clamp device with integral gravel guard, roof sump receiver, and dome strainer are engineered for long service life on flat and low-slope commercial roofs.

Key Features & Advantages

• Dual-Function Assembly: Primary drainage + overflow protection in a single unit to streamline roof detailing.
• Dura-Coated Cast Iron Body: Corrosion-resistant coating and robust metal components for harsh climates.
• Integral Protection: Clamp device with gravel guard and a dome strainer to maintain flow and resist clogging.
• Underdeck/Top-Set Integration (per model): Secure anchoring and consistent sealing through the deck plane.
• Outlet Flexibility: Multiple outlet sizes/types (e.g., no-hub) to match leader piping and hydraulic needs.

RD2130 Product View

Where the RD2130 Excels

• Commercial & institutional roofs (offices, schools, healthcare, municipal)
• Retrofits where combining main and overflow reduces roof penetrations
• Areas exposed to seasonal heavy rain or snow where overflow protection is critical

Sizing & Selection Tips

• Hydraulics first: Choose the outlet size/type based on rainfall intensity, roof area, and piping capacity.
• Membrane compatibility: Confirm clamp and flashing details align with the selected roof system.
• Maintenance access: Ensure clear access to the dome and gravel guard for periodic cleaning.

RD2130 — Installed on Low-Slope Roof

Installation Best Practices

• Place at low points: Coordinate slopes so water naturally finds the drain and overflow pathway.
• Achieve a watertight seal: Follow clamp/flash details precisely and verify membrane compatibility.
• Anchor securely: Use the appropriate deck receiver/underdeck clamp (when specified) for stability.
• Test overflow function: During commissioning, confirm the overflow path is unobstructed.
• Document & maintain: Record locations and service intervals; clear debris seasonally or after storms.

Case Study: Distribution Center Retrofit with RD2130

Challenge: A 240,000-sq-ft distribution center experienced intermittent ponding and emergency callouts during cloudbursts. Separate legacy overflow drains were undersized and hard to service.

Solution: The facility replaced scattered overflow fixtures with RD2130 combination drains at new low-point locations tied into existing leaders. Crews coordinated membrane tie-ins with the clamp and gravel-guard assembly and verified overflow performance during water testing.

Outcome: In the following storm season, the site recorded zero overflow-related leaks in the upgraded zones and reduced emergency maintenance by more than half. The integrated design simplified inspections and standardized spare parts across the roof.

Maintenance Checklist

• Clear dome/gravel guard each season and after major weather events.
• Confirm overflow pathway is open; remove ballast/debris that could bridge over the dome.
• Re-inspect clamp and membrane transitions annually to preserve watertightness.

Conclusion

The Zurn RD2130 offers reliable day-to-day drainage and built-in protection for extreme rain—within one durable, cast-iron assembly. With flexible outlet options and proven field performance, it’s a smart choice for new builds and retrofits seeking fewer penetrations, simpler layouts, and lower lifetime maintenance.