Zurn Z121 – 12" Diameter Cast Iron Roof Drain Assembly

Product Overview

The Zurn Z121 Roof Drain is a commercial-grade 12" roof drain assembly engineered for flat and low-slope roof systems. Featuring a heavy-duty Dura-Coated cast iron body and a secure flashing clamp/gravel guard, this drain is built to withstand harsh rooftop conditions while maintaining reliable water flow.

The Z121 offers multiple dome options—including polyethylene, aluminum, and cast iron—and supports a wide variety of outlet types (Inside Caulk, No-Hub, Threaded, and Neo-Loc). This makes it one of Zurn’s most versatile and field-proven roof drainage solutions.

Features & Benefits

• 12" (305 mm) high-capacity roof drain assembly.
• Durable Dura-Coated cast iron body for long service life.
• Combination flashing clamp and gravel guard for membrane security.
• Choose from poly, aluminum, or cast iron domes.
• Available with Inside Caulk, Threaded, No-Hub, or Neo-Loc outlets.
• Highly configurable for commercial, industrial, and institutional roofing.

Specifications

• Model: Z121
• Diameter: 12" (305 mm)
• Body Material: Dura-Coated cast iron
• Standard Dome: Low-silhouette poly dome
• Optional Domes: Aluminum, low-silhouette cast iron
• Outlet Options: Inside Caulk, No-Hub, Threaded, Neo-Loc
• Dome Open Area: 78 sq. in. (503 cm²)
• Approximate Weight: 22 lbs (10 kg)

Installation Tips

• Select the correct outlet connection for your piping layout.
• Tighten the flashing clamp evenly to secure the roofing membrane.
• Use optional extensions (-DP, -EB) for thicker roof assemblies.
• Choose dome material based on debris load and site conditions.
• Inspect dome openings regularly to maintain full drainage capacity.

FAQs

1. What dome options are available?
   Poly, aluminum, and cast iron.
2. Does the Z121 include a clamping collar?
   Yes, it includes a flashing clamp/gravel guard.
3. What outlet types are supported?
   Inside Caulk, No-Hub, Threaded, and Neo-Loc.
4. Is this suitable for commercial roofs?
   Yes, it is designed for commercial and industrial use.
5. What is the standard dome furnished?
   The low-silhouette poly dome.