Cement Concrete Ballasts for Rooftop Mounted Solar Structures By Surabh Ballast is a common alternative used on solar installations unable to penetrate either the roof or the ground. On low-sloped, flatter rooftops, many building owners don’t want to poke holes through the roof. Temperamental ground-mounts have some of the same concerns; solar arrays installed on top of landfill caps cannot penetrate that liner. That’s where solar ballast comes in. Concrete blocks are placed throughout a project to secure an array to the ground or the roof and prevent wind lift or other movement, all without having to make any (or as many) penetrations. Our concrete solar ballast units are used for flat ground and roof-mounted applications requiring ballast weight to secure panel arrays and provide the dispersion of point loads without the need for roof or foundation penetration. Solar ballast blocks are available in a range of weights and sizes to accommodate a variety of PV systems.