It's a familiar phenomenon: The remodel plan you begin with isn't exactly the one you end up with. For one Southern California family, a garage renovation evolved from a casual playroom for their two young kids to a well-appointed media room geared just as much to grown-ups. "When we started, we wanted a place for the kids to play their Wii Sports, which takes a lot of room," says the wife, and the seldom-used outbuilding near the pool offered a solution. Designer and builder Debra Kinner set about replacing its overhead doors with carriage-style units from Real Carriage Door Co. and building a wall—easily removable to allow for two cars should the family want to return the room to a garage someday—to create a narrow storage area accessible from outside. She put in a ceiling, finished the walls with insulation and wallboard, built an insulated subfloor, and added custom built-ins, a beverage fridge, and wiring for media equipment. As the couple watched the room take shape, they decided to upgrade the space even more, to one they could also use for pool parties. With the help of interior designer Allison Tannenbaum, in came natural-textured finishes like sea-grass carpet and grass-cloth wallpaper. The result is a comfortable—even elegant—room that the adults use as much as the kids. "We love it," says the wife. "It really completes our home."