A 20-foot concrete barrier typically measures 20 feet (about 6 meters) in length, 2.5 feet (about 0.76 meters) in width, and 3.5 feet (about 1.07 meters) in height. These dimensions make it a much longer and taller structure compared to the standard 10-foot barrier. Like the 10-foot barriers, 20-foot concrete barriers are made from high-strength concrete to provide durability and stability.