Instructions
Press "F3" at any time in-game to enter "Build" mode. Wait a few minutes for the mode to load.
Click the rooftop image on the "Build" menu.
Select one of the sloped rooftop options. This includes hip, 3-hip and half-hip rooftops. The roof will change in real time so you can preview the roof before saving it.
Press "F1" at any time to return to the game and save your changes.