A form assembly is provided for forming a concrete structure during setting of the concrete. Included in the form assembly are a first barrier assembly having a first inner surface and a first outer surface; a second barrier assembly having a second inner surface, a second outer surface, an upper barrier, and a lower barrier. A channel is defined by the first and second inner surfaces of the first and second barrier assemblies for pouring the concrete into the channel. The second barrier assembly includes at least one height adjustment assembly being connected at one end to the upper barrier, and at an opposite end to the lower barrier such that the upper barrier vertically reciprocates along a vertical guide of the upper barrier relative to the lower barrier for adjusting an overall height of the form assembly using the at least one height adjustment assembly.