Question: I am installing a concrete driveway and have been told that I should put some metal rods in the concrete, but nobody seems to know what size and how many. Can you help?
Answer: Adding rebar, which is the trade term for the metal rods that are embedded in concrete help prevent the concrete from cracking due to contraction and expansion. The rebar should be laid out in a grid that covers the driveway area and be in the middle of the slab. For details on the size of the rebar and how to position it, follow the link at the bottom of this entry.
Additional information on rebar.