Do low flow toilets clog more often?

PlumbingEPA WaterSense Sizing

Plumbing Fixture Water Savings Calculator

Calculate total gallons of water and utility dollars saved annually by upgrading old inefficient toilets, showerheads, and aerators to modern low-flow fixtures.

Plumbing Field StandardsEPA WaterSense Sizing

Engineering formulations calibrated to IPC, UPC & NEC specificationsSub-Zero Cold Climate Tolerances

Quick Summary & Key Answer

A family of four upgrading from older 3.5 GPF toilets to modern 1.28 GPF WaterSense toilets and low-flow 1.75 GPM showerheads saves over 24,000 gallons of water per year. At average municipal utility rates ($9.00 per 1,000 gallons combined water/sewer), this cuts utility bills by $220 to $350 annually.

EPA WaterSense toilets flush with 1.28 gallons (20% less than federal 1.6 GPF standard).
Toilets account for roughly 30% of an average home's indoor water consumption.
Water-saving aerators cut bathroom sink flow from 2.2 GPM down to 0.5-1.0 GPM.

Interactive Calculator

Adjust inputs for real-time results

Number of Household Members

Existing Toilet Flush Volume

Combined Water & Sewer Rate per 1,000 Gallons$/1k gal

$/1k gal

Calculated OutputWater Savings Verified

Annual Water Saved

24,966 Galgallons/year

Annual Utility Bill Savings: $225/year
Toilet Flush Savings: 16,206 gal/yr
Shower Water Savings: 8,760 gal/yr
10-Year Cumulative Dollar Savings: $2,247

Note: Upgrading from 3.5 GPF toilets to 1.28 GPF WaterSense models typically pays for itself in water bill reductions in under 2 years.

EPA WaterSense Performance Standards

WaterSense certified toilets must clear at least 350 grams of solid waste in standardized MaP testing.

Frequently Asked Questions

Common questions regarding this calculation and code compliance

Early 1990s 1.6 GPF toilets suffered from clogging, but modern 1.28 GPF toilets use computer-engineered fully glazed 2-1/8" trapways that flush better than old 3.5 GPF models.