Systems, methods and user interfaces for graphical configuration for ballasted roof mounts of non-rectangular solar arrays. A graphical interface may be provided to allow a user to view a roof grid, and place solar modules within the roof grid where desired, to account for various obstacles on a roof, to create a non-rectangular solar array. Using the layout of the array and various site parameters (building height, wind speed, etc.) and solar module parameters (wide, length, thickness, etc.), the system may calculate a complete bill of materials, customer pricing, ballasting requirements and overall roof loads for a complete solar project.