Used in modern construction to enhance the tensile strength of concrete, rebar is a bar made of steel that can be embedded in masonry and concrete. Although unfinished steel is the most common rebar material, newer rebar covered in epoxy or fibers have been developed for use in corrosionprone environments. The weight of a length of rebar varies depending on the diameter of the rebar and its material composition.
Rod Numbers

Rebar, short for reinforcing bar, is classified into rod numbers. Each number indicates the diameter of the rebar in inches. These numbers vary from #2, quarterinch rebar specified for lightduty construction, to #18 rebar, 2.257 inches in diameter. The number corresponds to an increase of oneeighth inch in diameter.
Rebar Weight

The rebar number is the most significant indicator of weight. Rebar number charts, available online, provide an indication of the diameter and weight that corresponds best to each rebar number. For the thinnest rebar, number 2, a one foot length weighs a mere .167 pounds. For the thickest, the same one foot length weighs 13.6 pounds.
Weight of a 20' length of rebar

Given the variation in weight based on rebar number, the weight of a twenty foot length will vary significantly. The thinnest rod of rebar, if extended to twenty feet, will weigh 3.34 pounds. At the other end of the spectrum, the thickest rod will weigh in at 272 pounds.
Number of Rebar Lengths in a Ton

One ton of rebar can be converted to 2,000 pounds. Based on the weight of a twenty foot length of rebar, one ton of rebar will contain at minimum seven lengths of #18 rebar. This same ton in #2 rebar would contain 598, twenty foot lengths.
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