Japanese Bathtub

The UX of Japanese automatic bathtubs

UX Design

Japan is generally a bit behind when it comes to digital UX, but the culture focused on kaizen (constant improvement) has created no shortage of examples of great UX in everyday life.

One can be seen in the humble bathtub. Japanese love to bathe and visit hot springs, and since the 1960s companies like Noritz and Rinnai have been developing technologies to bring the experience of a traditional bathhouse to the home.

Today, the majority of Japanese homes have a fully automatic bath system.

A typical modern Japanese bathroom (see the control panel?)

In most countries, having a bath is a pain. It’s hard to get the water temperature right. It’s easy to forget you left the water running and flood the bathroom. The water seems to go cold the moment you get in.

But the Japanese system removes these pain points with technology and user centered design.

The key is the boiler control panels, which are located both in the kitchen and bathroom, and act as a user interface for the hot water boiler, shower and bathtub.

Boiler Control Panel (Kitchen)

Why the kitchen? In addition to running the bath, you can also use it to change the water temperature for washing up or cooking. Most people bathe after dinner, so having a panel in the kitchen allows you to run the bath while doing the washing up.

Boiler Control Panel (Bathroom)

If you want to run a bath, you set the temperature and press the “auto bath” button on the control panel. If it senses you’ve forgotten to put in the plug, an announcement plays to remind you to do so.

You can then check the progress on the screen, and even select the percentage you want the bath to be filled.

When it’s ready, a song plays through speakers in both control panels.

The bath song

The most popular boiler maker in Japan, Noritz, has been using this same song for the last 20 years, which means that over 1/4 of the population hear it play in their homes each time they run a bath.

But there’s no rush to get in the bath after hearing the song — it senses when the water cools and recirculates warm water to maintain the temperature for as long as required.

Japanese families take advantage of this by having all the family bathe in the same water, which also saves electricity and water. (The bath is for soaking only and you wash your body/hair before getting in the water)

After getting in, you can relax and use the control panel to manually reheat the water, or even press the call button, which sends an announcement alerting those in the kitchen that you need assistance.

Newer systems even allow for you to talk to someone in the kitchen through a radio system — fancy a glass of wine?

Rinnai's radio features —perfect when you’ve forgotten towels or need to check on grandma

The “priority” button on the panel allows someone in the bath to have priority over setting the temperature while they are showering, preventing someone in the kitchen from changing the temperature.

The first boiler control panels were introduced in homes as early as 1961, and constant improvements with a focus on the user experience have made it what it is today — technology that blends into the background and allows you to enjoy the relaxation of a hot bath at the touch of a button.