Patent ID: 7552568

Claim:
Building material comprising at least a first plank and a second plank, said first plank comprising: a first planar decorative surface, having a polygonal shape defined by a plurality of edges; a second planar surface, displaced from the first surface by the edges; a female joining member on at least one edge, the female joining member comprising: a locking lip, having a first section extending mainly toward the first planar surface, followed by a second section extending mainly perpendicular to and toward the first planar surface; and a locking surface, the locking lip and locking surface defining a locking groove, the locking groove terminating in a locking edge; and said second plank comprising: a first planar decorative surface, having a polygonal shape defined by a plurality of edges; a second planar surface, displaced from the first surface by the edges; a male joining member on at least one edge, each male joining member comprising a locking heel extending at an acute angle with respect to the first planar surface; a locking face extending at an acute angle with respect to the planar surface, and a locking edge at the end of the locking face, whereby the female joining members on the first plank are configured to mate with the male joining members on the second plank to lock the first plank to the second plank by joining the planks through solely vertical motion.