Plastic building blocks

A plastic building block comprising:

• a rectangular body with a top side, a bottom side, a left side, a right side, a front side, and a rear side, the rectangular body including a plurality of vertical ridges located on the left side, the right side, the front side and the rear side and extending continuously from the top side to the bottom side thereof;
• a plurality of male positioning elements located at the top side and protruding from a top surface thereof, the male positioning elements configured to facilitate interlocking with an identical adjacent plastic building block stacked thereon;
• at least one circular conduit integrated within and penetrating through a center of the block, the at least one conduit configured to receive electrical wires, plumbing, or other utilities;
• a female recess element located at the bottom side defining a rectangular body inner wall extending upwardly from a perimeter of the bottom side, the rectangular body inner wall configured to snugly fit with the plurality of male positioning elements of the adjacent plastic building block, such that the plurality of male positioning elements abut the rectangular body inner wall, ensuring stable stacking and alignment of interconnected said blocks;
• wherein the plurality of male positioning elements comprise L-shaped guide elements, T-shaped guide elements and a circular guide element, each said guide element projecting upwardly from the top surface of the top side of the rectangular body, the circular guide element defining a top end of and extending upwardly around the at least one conduit, the T-shaped guide elements being positioned around a perimeter of the circular guide element and the L-shaped guide elements being positioned proximate a perimeter of the top side of the rectangular body;
• and
• wherein the building block is composed entirely of plastic and the interconnected blocks are configured to form exterior and interior walls of a building structure for human occupancy.