Even this most basic of bathroom fixtures is getting a revamp as manufacturers strive to make them more comfortable and efficient.

Trends include raising the toilet rim from the usual 14 inches to as much as 17 inches above the floor, which makes getting on and off easier.

Heightened efficiency is another selling point, as major brands attempt to improve upon the 1.6 gallons per flush that has been the legal threshold since 1994. More models with dual-flush technology use a mere 0.8 gallons for liquid-waste removal.

Many of today's toilets work effectively with just one flush, but we found some major performance differences among models, even within the same brand.

WHAT'S AVAILABLE

Most major brands offer an array of models in different designs and colors. But nearly all toilets fall into three basic types:

Gravity-feed. These most common toilets rely on water dropping from the tank into the bowl and trap to move waste down the drain. They're relatively quiet and can work with as little as 10 psi of household water pressure. But models that perform comparably to pressure-assist models typically cost as much, while lower-priced models often aren't up to the job. Price: $150 to $400.

Pressure-assist. These create the most flushing power overall. Pressure created when water displaces air within a sealed tank causes the water to thrust waste forcefully out through the bowl. But they require at least 25 psi of household water pressure to work properly. They also tend to be pricey and noisy. Price: $225 to $500.

Vacuum-assist. These are best where quietness counts. A vacuum chamber inside the tank works like a siphon to pull air out of the trap below the bowl so it can quickly fill with water to clear waste. Some vacuum-assist toilets perform well, though they still tend to have less flushing power than pressure-assisted models. Price: $200 to $300.

IMPORTANT FEATURES

Remodeling is the most common reason to buy a new toilet. You can choose between a round-front or elongated bowl, depending on space and personal preference. Two-piece designs, with a tank that bolts onto the bowl, tend to cost less than one-piece designs. You’ll also find several different rough-in dimensions—the clearance to the back wall needed to connect to the water line; the most common is 12 inches.

HOW TO CHOOSE

If you’re replacing a broken gravity-feed toilet, consider having it fixed, especially if it’s a low-flush model. A new flapper valve (about $5) or new fill valve (about $15) solves most problems and is easy to install. If you’ve decided to buy a new toilet, decide which type meets your needs—a pressure-assist for big families, a quieter gravity-feed or vacuum-assist for close quarters, say. Then keep these shopping tips in mind:

Check your water pressure. Before buying a pressure-assisted toilet, be sure that your home has the water pressure it requires. You can check the pressure yourself with a $10 gauge that connects to an outdoor spigot. If you need to adjust your water pressure, don’t go above 80 psi, which can harm toilets and other fixtures.

Consider cleaning. Two-piece toilets tend to be harder to clean, since the seam between the tank and bowl tends to trap grime. One-piece models from Eljer, Kohler, Toto, and others add style while eliminating the seam, but can cost $400 or more.

Choose colors with caution. More models are available in glacier blue, peach bisque, and other hues. But as with avocado green and harvest gold, some colors could go out of fashion.

Decide on shape. Toilets with a round bowl take up the least room and accept the widest variety of seats. More stylish elongated bowls allow a longer seat for more room and support for a variety of users.

Check the valve on gravity models. Models with flush valves 3 to 31⁄4 inches wide delivered more thrust than models with 2-inch valves. Check manufacturer specs before buying.

Copyright © 2003-2007 Consumers Union of U.S., Inc.

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