If it’s yellow…partial-flush it: Dual-flush toilet retrofit 1


Welcome to poop week (or two, sometimes these things take a while—ooh, let the potty humor begin) at The Organic Adventurer! We’re not squeamish about squishy stuff around here, so we decided that if you’re gonna do poop, you might as well go all in. Prepare yourselves for all things eco-poop!

In the spirit of going all in, we’re starting with people potty talk, specifically our adventures in dual-flush toilets. Many moons ago (look, if you want these jokes to get any better, you should probably just send your own!) The Organic Adventurer was looking for ways get greener and, as always, save a little green. Reflecting on my days of living and traveling overseas, where bidets are common and dual-flush toilets de rigueur, I thought, “That’s it. I’ll use less water and save money with the toilet.”

That makes a lot of eco-sense because, according to the EPA, toilet usage accounts for 30% of average household water use. So saving a third of the water from two-thirds of those flushes could add up to a lot of resource conservation. The remaining question was whether or not one could really save money with this eco-friendly move.

I looked into replacing my toilet with one designed specifically to be dual-flush. At the time, they ranged from $200 to over $1,500.

These days a dual-flush model can cost as little as $98. This one has a button-flush on top of the tank.

"WaterSense" is kind of like the EPA's Energy Star for toilets.

Not only was that out of my budget, but the potential seven cents in savings per day (at the 1.7 cents per gallon that I pay) meant that it would take a minimum of almost eight years to recoup the investment, much less to save any money—a little too long for me. So the next possibility was retrofitting my existing toilets.

First lesson to learn from my mistakes (and one of the reasons The Organic Adventurer exists): If you rely on someone else’s recommendation rather than investigating it yourself, make sure it comes with thorough research that examines all aspects of the issue or product. Personal experience doesn’t hurt either. I had been using a great website, called Practically Green, that lets its users make product recommendations. One of the products recommended was a retrofitting kit called the HydroRight Drop-in Dual-Flush Converter. My enthusiasm for the $20 price tag and the apparent ease of installation made me uncharacteristically impulsive, and I ordered it right away. Nine months was more my speed for return on investment!

A good, cheap solution under certain circumstances

Mr. Organic Adventurer was less enthusiastic, seeing as how his hands would be the ones all over the toilet, but he patiently read through all of the instructions and specifications. The first sign of trouble came when he discovered that because we did not have the flapper-style flush mechanism, we would have to also purchase the $12 flush valve. Yeah, that’s where the thorough research would’ve been handy. At this point, though, the toilet’s works were in pieces on the bathroom floor and Mr. OA wasn’t about to reassemble the throne just to disassemble it again later. Off we went to Home Depot, where we discovered that not only could I have paid less for the product that I purchased had I bought it there instead of ordering it online, but there was also a kit including both items for $24. We bought the kit and returned my purchase.

Once home, the 10-minute installation was a breeze. Trying to adjust the beast  to actually flush while still providing maximum water savings was a different story. After four hours and way too many test flushes (some involving, I kid you not, a timer and a ruler) we admitted defeat and called the product’s customer service number. They were, to say the least, not easy to reach. So we spent five days with a non-functional toilet. Mr. OA generously pointed out that at least I hadn’t insisted that we do both toilets at the same time, so we had a backup.

The original handle

The new handle—small button for partial flush, large button for full flush

On dual-flush models and in Europe, the "handle" is usually on the top of the tank. You may also see models that have tanks behind the wall and an almost flat wall panel for the flush buttons.

When we finally reached someone who could help us with the adjustment, he was extremely patient and helpful. After two hours on the phone, though, he finally admitted that because we already had a relatively water-efficient toilet, we could only increase its efficiency but so much. The modern standard for water-efficient toilets such as ours is 1.6 gallons per flush. The product, he said, was really designed to retrofit pre-1995 toilets that use anywhere from 3.5 to 7 gallons of water per flush.

The old works

The new works

Our dilemma, then, was whether to keep the retrofit kit or revert back to the original iteration of the toilet. Based on the tank water level measurements, I estimated that I was saving more like .3 gallons per partial flush rather than the advertised .7, which meant a savings of 3 cents a day. That translated to a little over two years to start seeing any return on investment. Not too bad, but the fact that our utility charges us per 1,000 gallons meant that we wouldn’t be able to save enough water with a dual-flush toilet, or even two, to budge the utility’s round number. Mr. OA was also annoyed that you had to hold the partial-flush button for a precise number of seconds to make it actually flush. Still, not flushing 657 gallons of water a year is nothing to sneeze at, environmentally speaking, so I was in favor of keeping the new works. Mr. OA didn’t feel like doing any more plumbing work than necessary, and we’d already disposed of the original works; reverting would mean another trip to the hardware store. So we compromised by keeping the new dual-flush works in the master bath toilet and not converting the toilet in the guest bath.

The lesson here is that if you have a pre-1995 toilet and want to cheaply save a lot of water, a dual-flush retrofit kit is a great option. Whether or not you can save any money that way would depend on the original capacity of your toilet (and, therefore, how much water you were saving) and your utility’s billing practices. If you have a 1.6-gallon toilet, you could likely achieve the same water savings by putting a brick (or anything else that displaces water) in the tank and calling it a day. Just make sure there’s still enough water to complete the flush. And those rumors about bricks  breaking down in the tank? That’s a load (had to get one more in there!) as far as I know from the personal experience of having a brick in a 1971 toilet for about 30 years. By the time I replaced the toilet during a bathroom remodel, you could still have built a house with that brick.

Looks like somebody found a solution for saving water with their toilet!

What’s your experience been with reducing water usage in the potty closet? Do you let it mellow? Do you co-pee? Have a composting toilet? What do you want to hear more about? Don’t be shy; we’d love to hear your stories, suggestions and comments…yes, that includes potty humor!


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One thought on “If it’s yellow…partial-flush it: Dual-flush toilet retrofit

  • The Organic Adventurer

    An email subscriber mentioned that she filled a water bottle with sand and water to displace water in her toilet tank. That’s a great idea! She cautions: “Make sure to put sand in the bottle to weigh it down or it could float up and interfere with the toilet’s works.” We’d love to hear other solutions; what have you used to displace water in your toilet tank?