The Duo-Flush Design Challenge

How do you make something that takes a plumber 2 hours to install into something a novice can install in 15 minutes with no tools? Fluidmaster was facing countless issues from slow in-store purchases to frustrated customers trying to install an unapproachable product on their own.




Current (Failing) Product VS. the Competition

The current product had numerous issues, the most significant being that users were required to hack the excess overflow tube with a saw. (Yikes!) Fluidmaster’s current product is on the left, and the competition (boasting a 10-minute install with no tools) is on the right.




Understanding the Install Experience

In order to benchmark install results, John set up a number of observational install tests with both plumbers and DIY’ers. Surprisingly, it took plumbers an average of 1.5 hours to install the current retrofit valve — a task that required tank removal and the use of a hacksaw to cut the overflow tube for low-boy toilets. It was clear at this point the product needed a complete overhaul.




Usability and Ergonomics: Knob Design and Testing

Touch points are one of the most important elements of good design. Good ergonomic design can help guide users toward operating new products, resulting in an intuitive user experience. John Proksch-Whaley 3D-printed a collection of knobs and blind-tested them with users in the field for direct feedback.



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Simplifying the Install Experience

Calling a plumber is incredibly expensive, but most self-proclaimed DIY’ers aren’t willing to do things themselves when it comes to their toilets. As an off-the-shelf dual flush retrofit, the Duo-Flush unit had to be installable not just by DIY’ers, but by Novices as well.




Turning Findings into Approachable Design

John recommended moving all touch points to the top of the device to get the user’s hands out of the water in the toilet tank. Moving the touch points up meant the user could now also read dials to make an informed decision as to where to adjust the floats to. Creating a highly legible UI led to dramatically improved install times.





The End Result: A Highly Usable, Approachable Product

What started out as a 2-hour install for a plumber ended with a 15-minute install for novices. The best part is users were no longer required to hack the overflow tube off with a saw, and the toilet tank no longer needed to be removed to install the new duo-flush valve.




Making a Complex Product Approachable

After designing the user experience and completing the industrial design, John created a user manual from scratch to help customers better understand the install experience. Illustrations were created using 3D models in Solidworks, and rendered in Bunkspeed.




Packaging Fluidmaster’s Duo-Flush

The purchase decision happens in the store aisle, which means the customer has to understand the product before taking it home. Through conducting observational research in store aisles and talking with plumbing associates, John discovered that customers will do anything they can to get into a box to determine whether or not the project is doable. This means the box needs to be openable without being destroyed. Fluidmaster’s current product was in clamshell packaging, which was impossible to open in store aisles. This led to slow purchases, as well as a huge return rate for those who did purchase it only to get home and realize the product was virtually not installable without a plumber.





In Stores Nationwide

Fluidmaster’s new Duo-Flush product is available in some of the nation’s biggest retailers, including Home Depot and Lowe’s. The rate of returns has drastically decreased, and Fluidmaster has once again reclaimed the market from some of their toughest competitors in the do-it-yourself dual flush retrofit market.