Problems With Dual Flush Toilets

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Dual flush toilets may require more cleaning than conventional models.
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Most American homes come with single-flush toilets: one handle, one flush. But in Australia, New Zealand and Japan, other styles of toilets dominate. A dual-flush toilet is one equipped with two different flushes: a smaller flush for liquid waste and a larger one for solid waste.


Ask Jon Eakes explains that the dual flush conserves the use of water, which is not only better for the environment, but decreases utility bills. Some governments offer rebates to encourage households to install dual-flush toilets in their homes, but there are still some issues with this type of toilet.

Problems With Dual-Flush Toilets

The main disadvantage to dual-flush toilets is that they're a more expensive purchase, even though homeowners may end up saving money in the long run with declining water usage. The upfront cost is due to the addition of the valves and internal pieces that add the second flush option. Dual-flush toilets work much the same as single-flush toilets, just with a second option. However, a dual-flush toilet can present a few unique problems.


Because the purpose of the dual-flush toilet is to conserve water, the water level in both the bowl and the tank of the toilet is significantly lower than in a single-flush model. This means the toilet bowl can become visibly dirtier and may require more frequent cleaning, especially for those used to a single-flush toilet.

In addition, the reduced flow through the pipes means a lower volume of water going through the pipes. This can lead to waste sitting in low spots and can sometimes lead to clogging issues. Because of this, dual-flush toilets are more suitable for bathrooms that are used frequently to prevent material from sitting in the pipes. Bathrooms that aren't used frequently may not be able to handle the lower flow.


Dual-Flush Toilets and Plumbing

Dual-flush toilets can also cause issues in older houses that may have depended on a high-volume flush to keep the pipes clear. Newer models are likely to have plumbing that has been designed for lower-volume flush models of any kind, but older homes may have had the piping sized and spaced for a higher-volume flow. If the home is older than 30 years, it's worth having a plumber evaluate the piping to ensure it will be able to handle a water-conservative toilet.

Double-flush toilets can also suffer the same issues that most single-flush toilets do, occasionally exacerbated by the relatively low flow. Double-flush toilets might be designed to conserve water, but they are as likely to leak or run as a single-flush toilet. For example, the flapper or seal at the bottom of the tank is normally the No. 1 cause of a toilet tank running, and the problem can be worsened by the fact that users who aren't accustomed to the smaller amount of water in the bowl may flush multiple times in an attempt to "make up" for water they haven't seen.


Despite these disadvantages, a double-flush toilet can help decrease the water bill and make a small step toward helping to conserve water usage worldwide. Falcon Plumbing explains that your costs could be lowered by $100 per year with this type of toilet. The few issues they pose can easily be handled with a bit of awareness about the functioning mechanism, and, despite the upfront cost, this style of toilet can be worth the investment.



Danielle Smyth is a writer and content marketer from upstate New York. She holds a Master of Science in Publishing from Pace University. She owns her own content marketing agency, Wordsmyth Creative Content Marketing, and she enjoys writing home and DIY articles and blogs for clients in a variety of related industries. She also runs her own lifestyle blog, Sweet Frivolity.