Niagara Stealth Ultra High Efficiency Toilet Review: 800g Flush at Just 0.8 GPF

How powerful is the Niagara Stealth flush?

The vacuum-assist flush system is the key to this performance. Instead of relying on gravity alone, the Niagara Stealth uses a vacuum chamber that pulls water and waste through the 3-inch fully glazed trapway. This design creates a strong siphon effect that clears the bowl efficiently. The 3-inch trapway is wider than standard 2-inch trapways, reducing clogs and allowing waste to pass more freely.

Owner reviews consistently report that the flush handles solid waste well, with many noting it clears the bowl in one flush. Some users mention that larger loads may require a second flush, but this is uncommon given the 800g MaP rating. The flush is notably quieter than pressure-assisted or gravity-flush toilets, which is a major selling point for noise-sensitive households.

The MaP score of 800g places the Niagara Stealth in the top tier for water-saving toilets. For context, the EPA WaterSense program requires a minimum MaP score of 350g for certification. The Niagara Stealth more than doubles that requirement while using 37.5 percent less water than a standard 1.28 GPF toilet.

How water-efficient is the Niagara Stealth?

At 0.8 GPF, the Niagara Stealth saves significantly more water than standard 1.6 GPF toilets and even high-efficiency 1.28 GPF models. Over a year, a family of four could save thousands of gallons compared to older toilets. The exact savings depend on usage, but the reduction is substantial.

The vacuum-assist system is designed to maximize the cleaning power of each flush while minimizing water use. Unlike dual-flush toilets that offer a choice between 0.8 and 1.6 GPF, the Niagara Stealth uses 0.8 GPF for every flush. This simplifies operation and ensures consistent water savings.

WaterSense certification requires that toilets demonstrate a MaP score of at least 350g. The Niagara Stealth's 800g score far exceeds this minimum, proving that water efficiency does not have to sacrifice performance. This is a rare achievement in the toilet market.

Owner feedback highlights the water savings as a primary reason for purchase. Many users report noticeable reductions in their water bills after switching to the Niagara Stealth. Some note that the flush uses so little water that it can leave streaks on the bowl, requiring occasional brushing.

What do owners say about the Niagara Stealth?

Aggregated reviews from multiple retailers reveal several recurring themes:

Quiet operation. The vacuum-assist flush is remarkably quiet compared to gravity or pressure-assisted toilets. Many owners describe it as a "whoosh" rather than a loud flush. This is a major advantage for bathrooms near bedrooms or living areas.

Water savings. Owners frequently mention lower water bills after installation. Some report saving 2-3 gallons per flush compared to their old toilets. The savings are especially noticeable in households with multiple people.

Flush reliability. Most owners find the flush handles solid waste well. The 800g MaP score translates to real-world performance that clears the bowl in one flush for typical use. Some users note that larger or denser waste may require a second flush.

Standard height concerns. The 15-inch bowl height is standard, not comfort height. Taller users or those with mobility issues may find it less comfortable. This is the most common criticism in reviews.

Bowl streaking. Some owners report that the low water volume can leave residue on the bowl after flushing. This is more noticeable with solid waste and may require occasional manual cleaning.

Installation quirks. A few owners mention that the toilet requires a specific flush technique (holding the handle slightly longer) to ensure a complete flush. This is not universal but appears in some reviews.

How does the Niagara Stealth compare to similar toilets?

When compared to a typical 1.28 GPF gravity-flush toilet, the Niagara Stealth uses significantly less water per flush. Most 1.28 GPF toilets have MaP scores between 600g and 1000g, so the Niagara Stealth's 800g score is competitive. However, gravity-flush toilets often have larger water volumes that help with bowl cleaning and reduce streaking.

Against pressure-assisted toilets like the Toto Tornado or Kohler Class Five, the Niagara Stealth is quieter but less forceful. Pressure-assisted toilets use compressed air to create a powerful flush that can clear 1000g or more. They are louder and use more water (typically 1.28 GPF). The Niagara Stealth offers a quieter experience with less water but slightly less raw power.

Dual-flush toilets offer a choice between 0.8 GPF for liquid waste and 1.6 GPF for solid waste. The Niagara Stealth uses 0.8 GPF for every flush, which simplifies operation but means you cannot increase water volume for solid waste. This is a trade-off that some users may find limiting.

The Niagara Stealth's vacuum-assist system is less common than gravity or pressure-assisted designs. It offers a middle ground: more efficient than gravity, quieter than pressure-assisted. However, replacement parts may be harder to find than for more common systems.