What Is a Dual-Flush Toilet and How Do They Work?

What Is a Dual-Flush Toilet and How Do They Work?

14th Aug 2024

In the UK, a single person uses around 150 litres of water every single day. Plus, around 30% of the water that enters a home is used just to flush the toilet.

A dual-flush toilet could be the answer to a more environmentally friendly toilet solution. But what exactly is a dual-flush toilet, and why should you consider installing one in your bathroom?

In this guide, we'll cover everything you need to know about dual-flush toilets. We'll also explain the different types, with product recommendations from Brian Toward, Chief Executive Officer (CEO) here at Wholesale Domestic.

Contents

What is a dual-flush toilet?

A dual-flush toilet offers two flush options: a full-power flush for solid waste and a reduced-strength flush for liquid waste. This double functionality conserves water, making it an eco-friendly choice for any modern bathroom.

These toilets typically use built-in buttons on the top of the toilet cistern. Or, they use an additional  flush plate mounted to the wall, rather than a more traditional cistern lever that needs to be pulled down to activate.

Dual-flush toilets were first developed in Australia in the 1980s to address a general lack of water. Today, they are widely recognised for their efficiency and sustainability and are a common feature in homes and commercial buildings around the world.

"Using a dual-flush toilet is a great way to save water and money," says Brian. "It's perfect for anyone who wants to make their bathroom more eco-friendly. Unlike regular toilets that use the same amount of water for every flush, a dual-flush system lets you choose how much water you need each time, which can really help reduce your water bills."

How does a dual-flush toilet work?

Understanding how a dual-flush toilet works is crucial to appreciating its benefits. Unlike traditional, single-flush toilets, which use a single mechanism to release water, dual-flush toilets typically have two buttons.

The button size usually corresponds with the flush strength, with the smaller button releasing around 3 to 4 litres. In contrast, the other bigger button releases a larger volume – around 6 to 9 litres – for solid waste.

Brian explains: "It's pretty straightforward how a dual-flush toilet works. When you press the button for a half flush, a smaller valve opens up, so less water flows from the tank into the bowl. For a full flush, a bigger valve opens, letting more water through. This way, the toilet only uses the amount of water you actually need each time."

What are the benefits of dual-flush toilets?

When choosing a new toilet system for your bathroom, it's vital to consider all the unique benefits to ensure that you're installing a toilet that suits your bathroom habits. Dual-flush toilet systems offer a range of advantages, from cost-saving potential to environmental benefits.

Environmentally friendly

One of the main advantages of a dual-flush toilet is the positive environmental impact. A standard single-flush toilet uses around 13 litres of water per flush, which can very quickly add up. While this is beneficial for clearing solid waste, liquid waste can be effectively cleared with far less water, meaning you’re wasting a significant amount.

In contrast, dual-flush toilets have the option of using a more powerful flush to clear solid waste, and a half flush for liquid waste. Not only does this allow you to control the amount of water used depending on the type of flush required, but it also uses less water in general due to being more efficiently designed. In fact, by using a dual-flush toilet, each household could save an average of 19.2 litres of water per day.

Cost-saving

Brian says: "While investing in a dual-flush toilet can seem daunting at first, with the initial unit and installation costs sitting slightly higher than a regular toilet, this is a decision that pays for itself over time. The savings on water bills make it a cost-effective choice in the long run."

Fewer blockages

We’ve all been there. You flush the toilet only to find the water level rising instead of falling. Blockages can be annoying when you’re trying to flush the toilet and get on with your day, but a dual-flush system can significantly reduce the likelihood of experiencing one.

Brian explains: "A regular toilet uses a pressure syphoning system to flush. It has a vessel inside the cistern that traps and compresses air to push waste out of the bowl. Over time, this system can get damaged, making the flush less powerful and causing blockages."

"In contrast, a dual-flush toilet uses gravity to help the water remove waste – meaning it's far less likely to become blocked as the amount of gravity, of course, remains consistent at any time."

Modern designs and aesthetic appeal

In addition to their functional benefits, dual-flush toilets also come in various modern designs that can enhance the overall look of your bathroom. Whether you prefer a sleek, contemporary style or a more traditional look, there's a dual-flush toilet to suit your taste.

What are the components of a dual-flush toilet?

Knowing the components of a dual-flush toilet can help you understand how this innovative system works and why it's an excellent choice for your bathroom. Here, we'll break down the key components and their functions.

Flush buttons

The most distinctive feature of a dual-flush toilet is the flush buttons. These are often found on the top or side of the toilet tank and are designed to give you control over the amount of water used per flush.

Flush valve

The flush valve is a crucial component inside the toilet tank that regulates the release of water into the toilet bowl. In a dual-flush system, the flush valve is designed to operate differently for the two flush options.

Bowl

Brian explains: "Dual-flush toilets often have rimless or partially rimless bowl designs. This modern style lets water flow more effectively around the bowl during a flush, giving it a more thorough clean and preventing waste from sticking to the sides."

Cistern

The cistern, also known as a tank, is the part that holds the water used for flushing.

"Brian says: "In a dual-flush system, the tank is built to handle the double flush mechanism and ensure water is released efficiently for both options."

"To achieve this, the cistern has an internal flush valve that lets out different amounts of water depending on which button you press."

Types of dual-flush buttons

The most common dual-flush design is a circular shape made of two buttons: a larger crescent shape and a smaller oval. Other options include two separate buttons side-by-side or even a smaller button within a larger one.

These are available in a wide variety of colours and finishes, including brushed brass, gunmetal grey, and matt black – offering plenty of options to suit any bathroom.

A close-coupled toilet unit usually comes equipped with buttons or a cistern lever, meaning there are limited options for customisation. On the other hand, a wall-hung or back-to-wall design allows you to choose your own flush plate, as these are usually externally mounted.

No matter which design you choose, the formula is the same: the larger button will release more water for a full flush, while the smaller button is designed for a half-flush.

Types of dual-flush toilets

When choosing a dual-flush toilet, it's essential to consider the different types available. Each toilet has unique features and benefits, catering to various bathroom designs and lifestyle preferences.

Close-coupled dual-flush toilet

Close-coupled toilets with a dual-flush button are designed with a built-in dual-flush valve attached to the toilet bowl, creating a compact and streamlined appearance. They are easy to install and maintain, making them a popular choice for many households.

Recommended product: Jubilee Short Projection Close Coupled Toilet with Soft Close Toilet Seat

£139.95

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Brian says, "This toilet is perfect for smaller bathrooms because of its compact design. It also combines modern looks with practical features, like a soft-close seat and an efficient dual-flush system."

"It saves space and helps conserve water, making it both stylish and eco-friendly!"

Back-to-wall dual-flush toilet

Back-to-wall toilets are designed to sit flush against the wall, with the cistern either concealed within the wall or housed in a unit. This type of toilet creates a sleek and modern look while maximising floor space.

The dual-flush buttons are usually found on the top of the cistern, making it easy to identify which button is which.

Recommended product: Toilet Unit and Kingston Rimless Back-to-Wall Toilet Pan with Soft Close Toilet Seat

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Brian says: "This back-to-wall toilet has a classic design that fits with any bathroom décor. The dual-flush cistern is hidden in a sleek casing, giving it a minimalist look while still offering a full or half flush. It's perfect for anyone looking for a mix of functionality and modern style."

Plus, the rimless toilet allows the water to efficiently clear any waste, making it simple to keep on top of deep cleaning your bathroom.

Wall-hung dual-flush toilet

Wall-hung toilets are mounted on the wall, with the dual-flush cistern hidden behind the wall or within a specially designed unit. The dual buttons are attached to an external flush plate mounted to the wall, allowing you to customise your toilet’s design.

This type of toilet provides a sleek, floating appearance and makes cleaning the floor around it much more manageable.

Recommended product: Portland Wall Hung Toilet with Soft Close Seat

£359.95

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"This wall-hung dual-flush toilet is the perfect addition to any modern bathroom design," says Brian. "The concealed dual-flush cistern keeps things simple, while the wall-mounted chrome flush plate makes it easy to flush in a rush.”

The built-in valve allows you to choose between a 3-litre half flush for liquid waste and a 6-litre full flush, providing exceptional water efficiency.

To learn more about how to choose the best toilet for your bathroom, read our toilet buying guide.

Frequently asked questions

What happens if you push both buttons on a dual-flush toilet?

When you first install your dual-flush toilet, old habits may lead you to push the entire button after using the toilet. However, there's no need to panic about accidentally causing a double-flush. Pushing both buttons simultaneously typically results in a full flush, as the mechanism is designed to prioritise the larger volume of water needed for solid waste.

How do I use a dual-flush toilet?

Using a dual-flush toilet is simple: all you need to do is press the smaller button for liquid waste and the larger button for solid waste.

Are dual-flush toilets more expensive to maintain?

While dual-flush toilets may require occasional maintenance to ensure the mechanism works correctly, they are typically not any more expensive to maintain than a regular toilet. Frequent cleaning and following the manufacturer's guidelines will keep your toilet in good working condition for years to come.

Can I change my existing toilet to a dual-flush system?

"Yes, you can convert a standard single-flush toilet into a dual-flush system," says Brian. "To do this, you replace the toilet cistern with a dual-flush system, which includes a special valve that lets the toilet release different amounts of water depending on the flush needed."

"However, it's really important to make sure your existing toilet is compatible with this change and that your plumbing can handle a dual-flush system. That's why it's best to have a licensed plumber inspect your toilet instead of trying to do it yourself!"

Why does my dual-flush toilet keep running after flushing?

If your dual-flush toilet keeps running after you flush, there are a few issues that could be at play. One cause is that the flapper is stuck open. This is the rubber seal that covers the hole at the bottom of the tank, which opens to let water into the bowl after flushing. If your toilet is constantly running after flushing, this is the most likely cause.

Another potential problem could be that the chain which connects the flapper to the flush button might be too long or too short.

Additionally, debris in the tank – such as hair ties, dirt, or rubber bands – can also cause issues by blocking the flush valve and stopping it from closing.

To identify the specific problem with your toilet, you should have it inspected by a licensed plumber.

Find the best dual-flush toilet at Wholesale Domestic

At Wholesale Domestic, we're here to help you make the best choices for your home, ensuring you have a bathroom that is not only functional but also environmentally friendly.

If you need a new dual-flush toilet to refresh your bathroom, we have a huge range of traditional and modern styles to suit any space. From close-coupled to back-to-wall systems, explore our versatile options today. We also offer fantastic bathroom accessories to help you create your dream space, including bidets, toilet seats, and sleek flush plates.

If you're still debating the best toilet type for your home, read our comprehensive toilet buying guide or contact us today.