The Modern Toilet Buyer's Guide

The modern toilet in the United States is in a classification known as the Low Flow Toilet. In 1992, U.S. President George H. W. Bush signed the Energy Policy Act which made the 1.6 gallons per flush a mandatory federal maximum for new toilets. Low-flow toilets use 1.6 gallons or less per flush as opposed to 3.5 gallons. Early low flow toilets were problematic. Since the turn of the century the low flow toilet has improved a great deal.

When purchasing a new toilet, the two critical considerations are:

1. Flush valve aperture: buy a toilet with a high volume 3" flush valve opening on the tank, or larger if available. This makes the toilet flush with more force moving water from the tank to the bowl faster.
2. Gallons per flush: The higher the GPF rating the more water will move though the toilet. More water not only improves flush but also helps move waste material though your home septic system. The maximum GPF rating allowed under current law (2014) is 1.6 gallons.