How Much Weight Can a Countertop Support Bracket Hold? Countertop support brackets play a critical role in ensuring the stability and safety of countertops, especially in areas where they extend beyond the base cabinetry, such as kitchen islands or bar tops. Whether you are installing a heavy granite slab, a durable quartz surface, or any other solid material, having the right brackets in place is key to preventing sagging, cracking, or worse, catastrophic failure. But the question remains: how much weight can a countertop support bracket actually hold? The answer depends on the type of bracket you choose, the installation...