Vertical joint system and associated surface covering system

A vertical joint system for a substrate having an opposed major first and second surfaces, the joint system comprising:

• non-symmetrical male and female joints extending along opposite sides of the substrate, the male and female joints configured to enable two substrates with like joint systems to engage each other in response to a force applied in an engagement direction which is perpendicular to the major surfaces;
• the male joint comprising:
• a male protrusion extending generally perpendicular from the first major surface toward the second major surface and a male recess formed inboard of the male protrusion;
• a first male locking surface formed on a side of the male protrusion most distant from the male recess, and a third male locking surface being a surface common to the male protrusion and male recess;
• a male planar abutment surface extending from and essentially perpendicular to the first major surface;
• a rebate between the male planar abutment surface and the first male locking surface;
• the female joint comprising:
• a female protrusion extending generally perpendicular from the second major surface toward the first major surface and a female recess formed inboard of the female protrusion;
• a first female locking surface formed on a side of the female recess most distant from the female protrusion, and a third female locking surface being a surface common to the female protrusion and female recess;
• a female planar abutment surface extending from and essentially perpendicular to the first major surface;
• and
• a shoulder between the female planar abutment surface and the first female locking surface,
• wherein the locking surfaces are configured so that when a male and female joint of two substrates are engaged, the first male and first female locking surfaces engage to form a first locking plane, and the third male and third female locking surfaces engage to form a third locking plane, wherein the first locking plane inhibits separation of the engaged joints in a direction parallel to the engagement direction and the third locking plane inhibits separation of the engaged joints in a direction perpendicular to the engagement direction, and wherein the rebate is configured to rest on the shoulder when a male and female joint of two substrates are engaged.