What is a high-efficiency toilet (HET)?

An HET is a fixture with an average flush volume of 1.28 gallons per flush (GPF) or less. That’s 20 percent less than most toilets on the market today.

Do HETs qualify for the Toilet Rebate Program?

Many HETs do qualify for the City of Austin’s Toilet Rebate Program. However, all toilets on the list must meet specific performance criteria and be locally available. It is possible that there may be cases where toilets labeled "HET" do not qualify for the rebate program. Please consult our list of eligible toilets to make certain the model you’re considering is eligible.

What rebates are available?

There are several options in our Toilet Rebate program. If you meet all the qualifications for the Toilet Replacement Program (See application and guidelines), and:

• Are replacing a large capacity toilet installed before 1996:
  • Replace with any toilet on our eligible list and get up to $100 back, up to 3 per home.
• Are replacing existing 1.6 gpf toilets (up to 3 per home), even if obtained through our program:
  • Replace with an HET on our list and get a $50 rebate. Mark the "HET Upgrade" box on your application.
• Are building a new home:
  • Have your builder upgrade to an HET on our list and get a $50 rebate per toilet, up to 3 per home. Mark the "HET Upgrade" box on your application.

All Toilet Rebates require a completed application form. Please review list of eligible models. To qualify for special HET rebates, toilets MUST be marked as HET on our rebate list. Other toilets on our list are eligible for standard rebates only.

How long have HETs been available in the U.S.?

The first HET (a gravity-fed, dual-flush fixture) was introduced in the U.S. in late 1998 by Caroma. At that time, the dual-flush technology had been proven and available in the Australian marketplace for about 10 years. Prototypes of the second category of HETs (1.0-gallon pressure-assist fixtures) were field tested in 2001, but results weren’t ideal. Improved, effective technology hit the marketplace in 2003.

Today, a total of 86 different HET fixture models are available from 16 different manufacturers. The market is expected to grow by 50% in the next year as major manufacturers shift their focus to these exceptionally efficient, high-performance toilets.

Do HETs meet customer performance expectations?

Until recently, most of the HETs installed have been part of pilot programs developed by water utilities, and don’t necessarily represent the range of models available in the marketplace today. However, HETs perform better in laboratory tests than most of their "regular" counterparts, thanks to extensive development and engineering. As with any equipment purchase, we recommend that you research the issue before buying to find the model that best fits your needs and budget. (See Maximum Performance (MaP) Testing of Popular Toilet Models, Veritec Consulting and Koeller and Company, to compare toilet performance.)

What about moving waste in the drainline?

Some customers are concerned about drainline transport (clogging and backups) with ultra-low (e.g., 1 gallon) flush volumes. A 2005 study by Koeller & Associates showed that HETs use sufficient water to move waste to the sewer in a typical home. The U.S. EPA had similar concerns when developing their new WaterSense program, but are now confident enough in the technology that HETs will be the first products to bear the new WaterSense label.