650 South Spring Street, Los Angeles, CA 90014, USA Official Site
This former Bank of America building was constructed in 1921 and used as the bank’s headquarters until 1972. Designed by the firm Schultze & Weaver, the classic venue is now used for weddings, galas, and filming.
In a flashback, Michael is finally chosen to design his own neighborhood in episode 1x13 "Michael's Gambit". Michael sneaks into the office to try and steal several Architect's pins but gets roped into a meeting with Shawn in episode 2x10 "Rhonda, Diana, Jake, and Trent".