Building blocks

Claim 1

A building block, including i. a unit having a plurality of sides including a top, a bottom and an opposite pair of sides, and ii. at least one integral complementary element symmetrically located with respect to a bilateral plane and adapted for effecting continuous weatherstops along said top and bottom sides when assembled with similar blocks, and iii. an integrally formed unitary continuous self-jointing element on at least one side of the unit, said self-jointing element being complementary with similar elements on other blocks, comprising a. an element inboard from a side wall, extending beyond said block and forming a doubled back male locking projection, which thus creates therewith, b. a contiguous element inboard from the opposite side wall, recessed into said block, complementary with said element (a) and forming a doubled back female locking recess complementary with said formed male locking projection, the shape, area and volume of said formed male locking projection and said formed female locking recess being substantially equal, said continuous self-jointing element being capable of joining with a complementary substantially similar self-jointing element on a side of another building block, the formed male locking projection of each building block being capable of snug universal positive two-way interlocking relationship with the complementary formed female locking recess of each adjacent similar block, thus enabling said block to be selectively reversible around a vertical axis, and thus enabling each continuous self-jointing element to universally join with a complementary self-jointing element on another block in a positive two-way interlocking relationship without disturbing the continuity of weatherstops along said top and bottom sides when assembled with other similar blocks.