Upon entering Union Station, L.A.'s iconic art deco train station, the finalists discover it's time for the famous white room challenge. During the episode, each finalist must transform individual blank white rooms into customized spaces that showcase their vision and ingenuity. In addition, for the first time in the show's history, the challenge will take place in a public area, where passersby will be able to view the designers' progress. The finalists, who must display their creativity with materials found at a home and garden center, also must demonstrate how they repurpose an existing item and how viewers might adapt the concept at home. Pop icon turned real estate entrepreneur and remodeling expert Rob Van Winkle, aka Vanilla Ice, will join Genevieve Gorder and Vern Yip in selecting which finalist achieved the most inventive design.