Toilet Basics

Gravity Fed (1.6 gpf, 1.28 gpf)

The most common type of toilet is a gravity-fed model, which relies on the weight of the water and head pressure (height of the water in the tank) to promote the flush. If you see free-standing water when peering down into the tank, your toilet is gravity fed. Dual-flush toilets are one type of gravity-fed toilet. Dual-flush toilets let users choose from one of two flush options depending on need: Users can push one button for a regular 1.6-gpf flush, or they can push another for a reduced flush using about 0.9 gallons of water.

Pressure-Assist (1.6 gpf, 1.1 gpf)

The pressure-assist toilet relies on air pressure within a cylindrical vessel, usually a metal or plastic material, inside the toilet tank. Air inside the vessel forces a vigorous, rapid flush. The vessel, along with a powerful flush, is a sign of a pressure-assist toilet.

Dual Flush (1.6 gpf, 1.0 gpf)

Dual-flush toilets give users two flush options: Tilt the handle up for liquid waste, which uses about 1.1 gallon per flush. Or push the handle down for a standard flush, which typically releases 1.6 gallons of water. Dual-flush toilets that have 1.6- and 1.1-gpf flush options meet HET criteria of averaging 1.28 gallons per flush or less (HET criteria for dual-flush toilets identifies the effective flush volume as the average of one high flush and two low flushes).

For more details of different toilet technologies click here.

Water Use: Toilets Using Less Water Than Ever

Toilets manufactured before 1980 usually need 5 to 7 gallons of water per flush (gpf ), and toilets from the 1980s typically use 3.5 gpf. In 1992, the U.S. government mandated that toilets use no more than 1.6 gpf, and California and other states are considering lowering toilet water consumption even more.

Replacing older, larger-use toilets with the newer models can result in significant water and sewer savings. If you replace a 3.5- or 5-gpf toilet with a 1.6-gpf toilet, you can save about 9,740 to 17,300 gallons of water per year. It’s a myth that more water will make a toilet work better. Today’s high-efficiency toilets use less water than ever, yet outperform many of the older, water-guzzling toilets.

Construction Details

Most toilets have either one- or two-piece construction and come with either a smaller, round bowl or larger, elongated bowl. Choose from various colors and heights, ranging from juvenile models typically found in preschools to chair-height models for large adults or people with special needs. White is still the reigning color, and the typical height from bowl rim to floor is about 15 to 17 inches. Most residential toilets are installed on the floor, but wall-mount models are an option for bathrooms short on floor space.

What Toilets are Made of: Vitreous china, or porcelain, is by far the most common construction material for the toilet itself in homes as well as in public restrooms. Stainless-steel models are typically installed in industrial and institutional applications, such as prisons and other high.

One or Two Pieces: Porcelain toilets have either one-piece or two-piece construction. The two-piece models are what most homes traditionally have, and they include a separate bowl and tank that are bolted together. One-piece models have a single, integrated tank and bowl design for a seamless, more contemporary look, but they’re pricier than two-piece models.

Floor or Wall Outlet: Drains for toilets are either on the floor, or in the wall. Wall outlets can be either 4 inches off the floor, or the fixture is "hung" on the wall over the outlet. Toilet Types

Toilet Dimensions Heights: Choose from various heights, ranging from juvenile models typically found in preschools to chair-height models for large adults or people with special needs. The typical height from bowl rim to floor is about 14 to 15 inches. As the population ages, toilet manufacturers have responded by raising the toilet heights to be comparable to standard chair height. In fact, the current wording for the Americans with Disabilities Act (ADA) is becoming the norm - 17-19 inches.

Rough-In for Installations: Most standard floor-mount toilets have a “rough-in” dimension of 10, 12 or 14 inches. To measure the rough-in distance, which must be known to select the correct toilet, measure from the wall to the center of the drain (the bolts that attach the fixture to the drain).

Toilet Bowl Styles Bowl Styles: Toilets also feature either a smaller, round bowl or larger, elongated bowl. The smaller, round bowl is ideal for compact spaces. Larger, elongated bowls with an extended rim length are more comfortable for adult use and improve hygiene. On the downside, they take up more space.

Toilet Color Color: If you can imagine a color, it may well exist. Black, blue, yellow, red—those colors and many more are out there, although white is still the reigning color. Choosing some shade of white or beige is a safer bet for ensuring design longevity. Nothing dates a bathroom more than fixtures with the harvest gold or avocado green colors that scream 1970.

Toilet seats of different colors and styles offer homeowners a less expensive way to infuse modern-day design into their toilets without committing to a color they can’t stand to look at years down the road. A toilet seat most often matches the porcelain construction and color of the toilet, because that’s how the set comes from the manufacturer. But buyers can select a separate seat made of different materials, such as wood, plastic or even glass, or in a different color or style scheme. Just be sure the toilet seat is compatible with the bowl type.