Does your state have HET requirements? California, Colorado, Georgia and Texas have strict standards that allow only HET to be sold and installed. That means you have to stick with either a 1.28 gpf low-flow toilet or a dual flush toilet. However, an HET toilet may also qualify for a rebate from your local water utility of up to $100, which can knock a nice chunk off your toilet purchase. To see if your water utility participates, check out the EPA website. Most online retailers will not ship a non-complaint toilet to these states; others will, but you may incur a penalty if you install it in your home.
What size is your rough-in? Toilets are designed to work with rough-ins (the concealed portion of your plumbing) of specific sizes. Some manufacturers offer multiple toilets of the same model number to accommodate different rough-in sizes, but you'll need to know before you make a selection.
What is your preferred bowl shape? There are three basic bowl shapes available, round, elongated and compact elongated. Elongated bowls tend to be more comfortable for adults, but round bowls may be a better fit for children. In addition, if you have a small bathroom or partial bath, a round bowl may better suit your needs. Elongated bowls tend to take up more space in the room and may interfere with opening doors or cupboards; in that case, a compact elongated bowl may be a wiser choice.
What side do you want your lever on? Depending upon the layout of your bathroom, you may need the trip lever that flushes the toilet located on one side or the other. Most toilets can be ordered with a right- or left-sided trip lever location. Be sure you order the one that makes the most sense for your bathroom so it's not too difficult to get to.
Do you mind a pushbutton model? Rather than a lever on the side, dual flush toilets usually have a two-button, pushbutton flushing mechanism located at the top of the toilet. Many owners like this, saying it seems like a more modern design; others hate it. We saw many comments that the buttons are too difficult for very young or very old to push. Also, some don't like not being able to use the top of the toilet for storing things like tissue boxes. If you don't think a pushbutton toilet is for you, there are some dual flush toilets that use a traditional trip lever.
We've talked a lot about water-saving toilets in this report, and there's a good reason for that. This free article from the editors of ConsumerReports.org offers an eye-opening glimpse into the water savings that can be achieved with lower-flow toilets, and saving water is becoming increasingly crucial as dwindling water supplies in many states reach critical levels. Currently, only California, Colorado, Georgia and Texas limit residents to only low-flow toilets (either 1.28 gpf single flush toilets, or dual flush toilets that average around 1.28 gpf) by law.
However, low-flow toilets are likely the wave of the future and experts say that more and more states are going to be making those limits mandatory over time. In addition, some communities require that residents replace all toilets with water consumptions above 1.28 gpf with low-flow toilets by a certain date. You can find more information about what your state requirements are at the National Conference of State Legislators website.
The good news is that manufacturers are responding with new technologies that can still flush efficiently while working with less water. Look for low-flow toilets to become even better performers as saving water becomes a highly-regulated fact of life.