Concrete Basics in Construction from Construction ...
Rebar is central to reinforced concrete, so a basic understanding helps. The various sizes are important to know: a #3 bar is 3/8" in diameter, a #7 bar is 7/8" in diameter, etc. The easy rule of thumb for rebar sizes is to take the rebar size and divide by 8 for the diameter in inches. Rebar. Diameter.