There's no official moment when you "grow up," but this could be a good unofficial sign: You've grown up when you stop having to build your own furniture.
According to a new study, people are most likely to shop at Ikea when they're 24 . . . and 30% of Ikea's customers are between 24 and 30. So when do you outgrow it? At 34.
That's when you start transitioning to places like West Elm, Crate & Barrel, and Williams-Sonoma.
Then, in your 40s, you start hitting Restoration Hardware and Pier 1 Imports.
Eventually, though, you stop focusing on buying furniture and stuff for your home . . . and you just start going to hardware stores. You're most likely to go to Home Depot when you're 48 . . . and Lowe's when you're 54.