All About Tankless Toilets

It's likely that you've heard terms like "low-flow toilets" and "dual-flush toilets" being bandied about. But have you heard about tankless toilets?

How Tankless Toilets Work

Well, they are exactly what their name implies: toilets without tanks. In order to understand how they work, first you need a basic understanding of traditional toilets. Normally, a toilet has two main parts: the tank and the bowl. The tank is raised above the bowl, and gravity aids in the flushing process. When the user flushes the toilet, a valve at the bottom of the tank opens, allowing the water that was sitting in the tank to flow down into the bowl and push the dirty water out through a siphon at the bottom of the bowl.

There are an increasing number of variations on the traditional toilet, but they all function on the same basic mechanisms. However, the tankless toilet alters the layout. Instead of storing water in a tank and using gravity to power the flush, tankless toilets hook up directly to your house's pipes, using an electric pump located in the bowl to power the flush. A valve is set to allow only a predetermined amount of water into the bowl when you flush, meaning the toilet should not be able to overflow. The draining works in the same way as in a traditional toilet.

There is still some debate as to the necessary width of the pipe supplying the fresh water to tankless toilets. There is a school of thought that believes ½" pipes are sufficient to provide enough water quickly enough, but another camp firmly asserts that the pipe must be 1" wide to ensure sufficient volume at an appropriate speed. If the water does not flow into the toilet quickly enough (ie. if the pipe is too small), the toilet will have prolonged or repeated flushing.

The Advantages to Tankless Toilets

Tankless toilets are smaller than traditional toilets and their pipes can enter either from a wall behind the toilet or from the floor. These factors allow more ways to customize your bathroom design. Plus, the smaller size saves on space.

Because tankless toilets use an electric pump, the bowl refills much more quickly than in traditional toilets, which is especially helpful when many people are waiting to use the bathroom.

Tankless toilets are not necessarily more environmentally friendly than traditional toilets. Since 1992, all new toilets in the US have had to comply to a 1.6-gallon-per-flush standard (older toilets use from 3 ½ to 7 gallons per flush). Tankless toilets also use 1.6 gallons per flush. However, the potential environmentally friendly factor arises in the case of malfunctioning toilets. A tank can spring a leak, causing the toilet to continually run. Without tanks and with such quick refill rates, there is no chance for a tankless toilet to run and waste water.

The Disadvantages To Tankless Toilets

Perhaps the biggest downside to tankless toilets is the electricity factor: If your power goes out, your toilet is not going to flush.

In addition, it may be frustrating to a seasoned do-it-yourselfer that most tankless toilet repairs require a professional. Between the electricity and the pipes hidden inside the walls, there are some complex factors when it comes to installing and fixing tankless toilets.

Is a Tankless Toilet for You?

Tankless toilets require a relatively wide supply pipeline in the house. If you are constructing a new house, you can install pipes to suit your needs. If you are replacing a toilet in a pre-existing home and you don't have the correct supply line to your toilet, the high pressure from the flush could damage your pipes. In that case, it's probably best to forgo the tankless idea, as it isn't worth the extra cost to redo or retrofit the pipes.

Speaking of cost, that is another serious factor to consider when deciding on a toilet type; tankless toilets run anywhere from $1,000-$5,000, and only a few companies make them so far, including Kohler and TOTO.

However, if you live in an area where power outages are infrequent and you want to update your bathroom with a modern, sleek look, tankless toilets may be for you.

Photo credit: TOTO