Ballast solar mounts are a solar panel mounting system designed for flat roofs with slopes of approximately 1 to 7 degrees. They are usually round or square frames made of aluminum, with a top clamp for the solar panel and a bottom "tray" that holds a counterweight.

Instead of relying on penetrations, sealants, and flashing like traditional methods, ballasted solar mounts use gravity to press the panels onto the structure. To hold the panels in place, solar installers place concrete blocks or landscape pavers in pans, although water jugs or sand are sometimes used. The tray section is designed to reduce pressure points and prevent standing water to protect the surrounding area.

Ballasted solar racks also feature a pre-specified slope to maximize productivity and reduce shading from surrounding panels (traditionally 10 degrees or less). This also ensures safety against wind lift by reducing the drag encountered by the panels. Once installed, ballast solar systems typically add two to six pounds of additional weight per square foot.