All About Dual Flush Toilet – A Detailed Guide

Are you by any chance redoing your bathroom, or are you building a new house are looking for attachments and accessories for your bathroom? There might be a lot of questions going on in your mind, and let’s not forget the dilemma over which attachment to pick.

If you have stumbled your way here, then you probably are on the lookout for some information on toilets, dual flush toilets in particular. Well, if that’s the case, then you are exactly in the right place because we are going to give you details on everything you need to know about them.

What Is a Dual Flush Toilet?

The first thing we need to do is know what a dual flush toilet is and how is it different from any other regular toilet we use most of the time.

This dual flushing system in toilets is similar to the normal toilets we have in most of our houses. However, the main difference is in the flush, of course. The difference you will see in the flushing system is that it has two buttons or handles instead of one. Each of the buttons uses different quantities of water to flush out the waste.

Pressing one button will use less water, while the other one would use more. This way, you will be able to limit the amount of water used according to your need.

A Japanese company named TOTO was the first to have developed a system and design such as this, it was back in the 1960s. Along with the dual flush, the system they designed would reuse the water used for washing hands to flush. It truly was a revolutionary idea at the time.

But this very first company to have practically designed a dual flush toilet is Caroma, which is an Australian Company. In that model of the toilet, 11 and 5.5 liters of water would be used if you push the buttons. However, things have changed, and less water is being used more sustainably at about 6 to 3 liters.

And this has slowly become a common staple in most bathrooms in countries like Singapore, Australia, and New Zealand, where most new buildings are required to install them in the bathrooms.

How Does a Dual Flush Toilet Work?

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The mechanism of a dual flush toilet is a little different even though from the outside, they look pretty much the same. Now, the flushing system in this has two settings for different types of waste. Pressing each of the push buttons will lead to a different result, or in this case, you might say, different quantity of water used.

When flushing out liquid waste, the toilet itself requires less amount of water than regular, so it seems a little redundant to waste the extra water when you have the option of using less.

It might not seem like a very large amount if you just consider it as a one-time thing, rather you will be saving water every time you discharge liquid waste by pushing the button that used less water.

As for the solid waste, the flush uses twice the amount of water for this task, this is required so that the waste is removed properly. But you will still be able to get a good flush using less water here as the tramway in this one is much larger.

How to Use Dual Flush Toilet – Which Button to Push

As I have mentioned a few times before, this toilet has two flush options. Now the use of these two options is very easy. You just have to know which button will release how much water. So, when you discharge liquid waste, you will obviously have to push the button made specifically for this and use less water.

In the case of solid waste, you would be pushing the other one so that there is enough water to flush out the waste. During this, you just have to be a little mindful of which button you are pushing as there is a chance you might push the wrong one, or might even push both at once, which would be counterproductive.

How Much Water Does the Dual Flush Use?

The two flush options use two different quantities of water to flush out the waste. Initially, these toilets would use 11.5 and 5 liters of water for the flush. 11.5 liters would be used for solid waste, and 5 liters would be used for liquid waste.

But now things are very different as the requirement of water is much lower, this mechanism and design have brought it down to 6 and 3 liters where 6 liters are used for the solid waste and for the liquid waste it is 3 liters.

How Much Does a Dual Flush Toilet Cost?

As it is with most products, the price will vary according to the brand and the quality of the toilet. So, if we are talking about a very basic dual flush toilet, it would cost you around $290 including installation, if you have prior experience installing toilets then you do not have to pay the $60 extra.

If you get something a little better than the standard model, then you should expect to pay around $260 to $320 and then pay an additional $90 for the installation. As for the best ones, you would be paying $450 in total.

How to Install a Dual Flush Toilet Kit

The first thing you would want to do when installing a dual flush toilet kit is to open the tank of the toilet and turn the water supply off.

Then you would have to take out all the old things inside, namely the handle and the flapper. Now you have an empty space in the middle portion of the tank. That is where you are going to slide the thin bottom part of the kit you bought.

Installing the handle is also pretty easy, most kits should have a button for the installation. You just have to put it in place of the old handle. That is really all you have to do if you decide to buy a kit which is very inexpensive.

However, I do recommend you read the instructions as not all dual flush toilet kits will be made the same way, it’s better knowing what you’re getting into from before.


If you are looking to save some money on your water bill and want to reduce the amount of water you waste, then surely, the dual flush toilet is the answer for you.

Now, you have all the information required before making a final decision!

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