Ultra-Low-Flow Toilet Stingy With Water Use


QUESTION: We still have the old original toilets in our house. Should we expect to save much money on our water bills by installing a new ultra-low-flow toilet? What types are available and do they flush adequately?

ANSWER: A new ultra-low-flow toilet can pay back its entire price many times with lower water bills over its life. Using less water keeps future water rates lower because fewer new treatment plants are needed. Excessive water usage is one of the greatest threats to the environment.

The most common ultra-low-flow toilets use about 1.5 gallons per flush (gpf). If your house was built before 1980, it probably has a 5.5-gpf toilet. In the early 1980s, 3.5 gpf became the standard. For a family of four, switching from a 5.5-gpf to a 1.5-gpf toilet saves about 24,000 gallons of water per year--a 70% savings.


Two common types of ultra-low-flow toilets are the gravity type and the flushometer tank type. The gravity type works like your standard toilet, but has a special bowl and trap design. This provides adequate flushing action with less water. Since it uses less water, it is quieter and take only 45 seconds to refill. Both types look like standard toilets.

Flushometer tanks use a special cylindrical chamber inside the toilet tank. As the chamber fills with water after a flush, the water pressure compresses the air in it. When the toilet is flushed, this compressed air forces out the water under pressure to give a forceful positive flush.

The bowl is cleared in only 10 seconds, but it takes about 60 to 90 seconds to refill the tank. Flushometer tank toilets work best if you have normal to high water pressure in your area. Check with a local plumber about your water pressure.

There are also some super-low-flow toilets that use less than one-half gpf. One type uses an electric air compressor to assist in the flushing. This produces a very vigorous flush to clear the bowl with almost no water.

Another toilet uses electric elements to incinerate the waste instead of water to flush it away. As the waste is vaporized and burned to a fine white powder, the vapors are vented outdoors. Since it is incinerated at very high temperatures, germs are eliminated.

When you buy a new toilet, check the specifications carefully. Many so-called water saver toilets are just a standard 3.5 gpf design. The prices for ultra-low-flow toilets range from about $90 to more than $300. They are available in most designer colors.


You can write to me for Utility Bills Update No. 089, showing a buyer’s guide of 20 manufacturers of ultra-low-flow toilets, model numbers, water usage (gpf), type, price range, number of colors, and chart showing the water bills savings by installing a new toilet. Please include $1 and a self-addressed stamped business-size envelope. Send your requests to James Dulley, c/o Los Angeles Times, 6906 Royalgreen Drive, Cincinnati, Ohio 45244.

Balloon, Platform Framing Defined

Q: What is the difference between balloon-framing and platform-framing construction. Which type is most energy efficient?

A: In balloon-framing the wall studs run from the foundation all the way up to the roof. This is often used in two-story construction or in rooms with high cathedral ceilings. Platform-framing builds the second floor walls separately on top of the first floor.

With proper construction, there is not a significant difference in energy efficiency. Since balloon-framing is generally stronger and more rigid, it may result in fewer air leaks over time.

Letters and questions to Dulley, a Cincinnati-based engineering consultant, may be sent to James Dulley, Los Angeles Times, 6906 Royalgreen Drive, Cincinnati, Ohio 45244.