10" Rough-In Two-Piece Round Front Toilet, 1.28 gpf, White

Gerber Viper® 1.28 GPF Round Front Two-Piece Toilet – 10" Rough-In – Model GWS31500

The Gerber GWS31500 Viper® is a two-piece round front toilet configured for installations requiring a 10" rough-in. Designed for efficiency and reliability, this model features a high-performance 1.28 GPF rating and meets WaterSense® certification standards. The compact bowl design is well-suited for smaller bathroom layouts or retrofit applications.

Its flushing system combines a 3" flush valve with a dual-fed siphon jet, ensuring consistent performance and effective bowl clearance. The fully glazed 2" trapway and rigid flapper components reduce the risk of clogs and contribute to low-maintenance operation in both residential and light commercial environments.

Performance Features

• Flush Volume: 1.28 gallons per flush (WaterSense® certified)
• Trapway: 2" diameter, fully glazed for smooth waste passage
• Flushing System: Dual-fed siphon jet with 3" flush valve for reliable evacuation
• Bowl Type: Round front; ideal for applications where space is limited
• Fill Valve: Includes Fluidmaster® 400A for quiet, efficient tank refill
• Flapper: Rigid, corrosion-resistant construction for durability

Dimensional and Installation Information

• Rough-In: 10 inches
• Configuration: Two-piece (bowl and tank sold together)
• Installation: Floor-mounted, standard three-bolt pattern
• Color: White
• Material: Vitreous china
• Certifications: WaterSense®, ADA height not applicable to this model

Installation Considerations

The GWS31500 is designed for fast installation with integrated bolt caps and a simplified tank-to-bowl connection using non-corrosive brass bolts. While it can be installed by experienced personnel, proper sealing and alignment are essential to avoid post-installation issues. A licensed plumber is recommended to ensure compliance with local codes and to optimize function.

Application Scope

This model is suitable for compact installations where wall clearance is limited, including powder rooms, secondary bathrooms, and retrofit projects where a 10" rough-in is already present. Its round bowl and compact tank profile reduce projection while maintaining high-efficiency flushing.

Component Highlights

• Compact Footprint: Round front bowl conserves space without compromising performance
• Durability-Focused Hardware: Includes brass tank-to-bowl bolts and a corrosion-resistant flapper
• Quiet Operation: Fluidmaster® valve minimizes refill noise and supports consistent tank levels