[3rd_gear_Ted]

Our home in Baja was built in 1987 with cinder block, rebar & concrete.
It sits right next to the ocean.

If the rust starts going on the rebar, it will continually expand and migrate the length of the rebar.
There should be at least three inches of concrete surrounding the rebar core in the vertical plane.
My concrete support beams have 4 inches on the top & bottom with two inches on the sides around the rebar core. Those pictures taken in Florida show a lot less concrete surrounding the rebar. Mexican concrete (Cemex) is better than the state side recipe by far. (they have No wood, so they have to have good concrete)