The 1000 Floor Elevator

The “The 1,000 Floor Elevator” is an infamous Interview Design Challenge by Google: “How do you design an interface for a 1000 floors elevator?”.

How do you design an interface for a 1000 floors elevator?

As a 2005 student assignment at CMU

The question has also made appearances in design curricula. Dan Saffer included it among a series of simple, foundational exercises “Five Easy Pieces” at the start of his 2005 Visual Interface Design class (at CMU). This is how he formulates the exercise:

Design an elevator for a building with 1000 floors. Not an elevator system, a single elevator that can travel from the ground floor to the 1000th floor. I expect you to address at least the following:
– How a user selects a floor
– How the floors are displayed to those in the elevator
Your solution should be printed out and mounted on thick black paper for presentation.
[Courtesy John Zimmerman]

As a student assignment at CCA

Other iterations of this assignment were given at CCA (California College of the Arts) as part of IxD Studio Foundations.

In 2011, William Clark published his version on his Behance profile, mentioning that “This was our first challenge in CCA’s Intro to IxD class”.

In 2015, designer Kristine Yuen shows the results in her portfolio. This is her description of the assignment:

Over the course of 1 week, we had a design challenge to come up with an elevator interface that services 1000 floors in a building. The prompt states that the building is for mixed retail, commercial and residential inhabitants. Additionally, we must consider how a rider selects a floor, how progress and floors are displayed, and how to access a secure floor.
Given this was my first assignment in the program, I learned a lot more about how interaction models work together in an ecosystem.

Further reading

Some articles on this design challenge: