The Incident

The location for the stairs was a real building located near the area of Churubusco in Mexico City. It was only 30% occupied at the time of the shooting, which is why they allowed the film to be shot on their emergency stairs. Most of the neighbors never even realized a film was shot at their emergency stairs, as they always took the elevator, but the crew used to laugh at how funny it would be if eventually a certain neighbor would want to take the stairs because the elevator was too slow or something like that, and find out an entire crew of 30 persons working there, drawings on the wall and a lot of crazy stuff. Eventually, it did happen, but the people who came in and found everything were not mad. They were, in fact, extremely surprised and happy, taking pictures of everything, as if they were entering a museum, and begging production designer Adelle Achar to never remove any of the art from their stairs.

Referenced in Film Junk Podcast: Episode 665: Incredibles 2 (2018)