Abstract: The ceramic tile installation system includes a plurality of shaped inserts adapted to be insertably mounted inside an opening or a shaped recess of predefined depth in a wall niche preform; the plurality of inserts having shapes configurable, alone or in combination, to conform to the shape of the recess; each insert having an enclosed sidewall of a given width, the sidewall width being larger than the depth of the of the preform recess to thereby provide a ledge for supporting tiles as the tiles are being installed around the shaped recess. The inserts may include reinforcing ribbing disposed along the interior of the sidewall.