Niagara Stealth Dual-Flush 0.8/1.1 GPF Two-Piece Elongated Toilet

Niagara Stealth Dual-Flush: Vacuum-Assist Ultra-Low Flow Toilet

The Niagara Stealth Dual-Flush Two-Piece Elongated Toilet is Niagara Conservation's flagship product — and the most distinctive flush technology in the US toilet market. The Stealth uses a patented vacuum-assist flush mechanism that delivers powerful bowl clearing at 0.8 GPF light flush and 1.28 GPF full flush — well below WaterSense requirements while maintaining MaP 800g+ flush performance. Niagara Conservation built its entire brand around water conservation engineering, and the Stealth is the flagship demonstration of how far ultra-low-flow flush technology has advanced. At $279-$369 retail, the Stealth competes with premium WaterSense alternatives while delivering meaningfully better water savings.

How Vacuum-Assist Flushing Works

The Stealth's vacuum-assist mechanism uses a sealed inner chamber that creates negative pressure as the tank fills. When the user activates the flush, the vacuum is released along with the water flow, creating a high-velocity siphonic action that clears the bowl on first flush — even at 0.8 GPF light flush volume. Compared to gravity-only flushing (the standard approach in most toilets), vacuum-assist generates more flush energy from less water. Compared to pressure-assist toilets (which use compressed air and are notoriously loud), vacuum-assist is quieter — comparable noise to a standard gravity-flush toilet.

Dual-Flush 0.8/1.28 GPF

The Stealth's dual-flush configuration:

• Light flush (0.8 GPF): 38% less water than WaterSense 1.28 GPF designs; handles liquid waste cleanly
• Full flush (1.28 GPF): matches WaterSense full-flush volume; handles solid waste reliably
• Average per-flush usage: approximately 0.95 GPF (assuming 70/30 light-to-full ratio typical residential use)

This delivers approximately 25% additional water savings vs. WaterSense 1.28 GPF dual-flush designs — meaningful over a household's 5,000+ annual flushes.

Water Cost Savings Over 10 Years

• vs. WaterSense 1.28 GPF dual-flush: approximately 1,650 gallons/year saved, $20-$30/year, $200-$300 over 10 years
• vs. Standard 1.6 GPF: approximately 3,250 gallons/year saved, $40-$55/year, $400-$550 over 10 years
• vs. Pre-1992 3.5 GPF: approximately 12,500 gallons/year saved, $150-$220/year, $1,500-$2,200 over 10 years

The Stealth's $50-$100 price premium over standard WaterSense alternatives pays back in 3-5 years through water cost savings alone in most US municipalities.

Bowl Performance at Ultra-Low Flow

The Stealth's MaP rating (Maximum Performance) is 800g+ — meeting the same threshold as standard 1.28 GPF WaterSense toilets despite using less water. Independent testing has demonstrated the vacuum-assist mechanism maintains flush performance over 10+ years of use; the original Stealth designs from the early 2010s are still performing in installation studies.

Quiet Operation

Unlike pressure-assist toilets (Sloan, Flushmate), which are notoriously loud due to compressed air discharge, vacuum-assist runs at noise levels comparable to standard gravity-flush toilets — approximately 55-60 dB during flush. This is the Stealth's key advantage over pressure-assist alternatives that also deliver low-flow high-performance flushing.

Two-Piece Construction

Standard two-piece (tank and bowl separate). Tank-to-bowl gasket included. Easier shipping and installation than one-piece alternatives.

Specifications

• Form factor: Two-piece floor-mount
• Bowl shape: Elongated
• Material: Vitreous china
• Flush volume: Dual-flush 0.8/1.28 GPF (avg ~0.95 GPF)
• Flush technology: Vacuum-assist siphonic
• Rough-in: 12 inches
• Seat height: ~17 inches (ADA comfort height)
• Seat: Sold separately ($20-$45)
• Color: Glossy White (standard), Bone (limited)
• Warranty: 10 years vitreous china, 1 year mechanical (Niagara's stronger china warranty than most competitors)
• MaP rating: 800g+
• Certifications: WaterSense PLUS (exceeds standard), CalGreen Premium, EPA ENERGY STAR

Installation

• Standard 12-inch rough-in
• Cold water supply line
• Wax ring + flange bolts ($15-$25)
• Seat purchased separately
• Two-piece installation: 1.5-2 hours, $150-$350

Care

• Standard porcelain cleaners safe
• Avoid pouring cleaning chemicals directly into the vacuum chamber (may degrade seals over time)
• Pumice stones safe on bowl interior
• Periodic inspection of the vacuum mechanism every 5-7 years for seal integrity

Pros

• Industry-leading water conservation — 25% better than WaterSense 1.28 GPF designs
• MaP 800g+ flush performance despite ultra-low water volume
• Quieter than pressure-assist alternatives (Sloan, Flushmate)
• 10-year vitreous china warranty (stronger than most competitors)
• CalGreen Premium and ENERGY STAR certifications enable utility rebates
• Long-term water cost savings recoup price premium in 3-5 years
• Available through Home Depot, Lowe's, Wayfair
• Two-piece form factor for easier installation and serviceability

Cons

• Vacuum-assist mechanism is a specialty technology — fewer plumbers familiar with service
• 1-year mechanical warranty short relative to china warranty
• Seat sold separately
• Only Glossy White and limited Bone — no modern aesthetic color options
• Niagara brand recognition lower than mainstream alternatives
• Vacuum mechanism may require specialty parts for repairs (not generic Fluidmaster)
• Traditional aesthetic — not designed for modern design renovations

Who Should Buy the Stealth

• Households prioritizing water conservation as primary buying factor
• Properties in drought-affected regions or with high water costs
• Buyers eligible for CalGreen, ENERGY STAR, or local utility water-saving rebates
• Eco-conscious renovations where flush technology is part of the sustainability story
• Long-term ownership where 10-year water cost savings compound meaningfully
• Commercial installations subject to strict water conservation regulations