Fence or wall
The Wikipedia page for Fence notes that "a fence differs from a wall in not having a solid foundation along its whole length."
The page for Wall leaves the distinction more open with "The conventional differentiation is that a fence is of minimal thickness and often open in nature, while a wall is usually more than a nominal thickness and is completely closed, or opaque. More to the point, an exterior structure of wood or wire is generally called a fence—but one of masonry is a wall."
Забор из бетонных плит - wall?
А из фигурных плиток (не знаю, как их правильно обозвать, обычно по 0,5 м высотой)?