Decorative wall covering with improved interlock system

A wall covering for mounting on a support surface comprising:

• a plurality of panels each having a body portion formed with simulated building elements having non-planar forward facing and rearward facing surfaces, each panel having a substantially planar upper marginal edge region including an upper edge of the panel and a substantially planar lower marginal edge region including a lower edge of the panel;
• the panels being mountable on the support surface in a plurality of horizontal courses with the lower marginal edge region of each panel in one horizontal course overlying the upper marginal edge region of a previously mounted panel in a downwardly adjacent horizontal course,
• the upper marginal edge region of each panel having a continuous upper interlock flange depending forwardly and downwardly from the upper marginal edge region at a position below the upper edge of the panel and extending substantially the length of the panel, the upper interlock flange being forwardly spaced apart from the upper marginal edge region by a plurality of substantially horizontal support plates so as to define a vertically extending gap between the upper interlock flange and the upper marginal edge region, the support plates spaced apart from one another so as to define openings therebetween, the support plates separating the upper interlock flange from the upper marginal edge region so that the upper interlock flange extends substantially parallel to the upper marginal edge region that it overlies,
• the lower marginal edge region of each panel having at least one lower elongated interlock flange extending rearwardly and upwardly from the lower marginal edge region at a position spaced apart from and above the lower edge of the panel and extending substantially the length of the panel, the lower interlock flange being rearwardly spaced apart from the rearward facing surface by a plurality of substantially horizontal lower support plates so as to define a vertically extending gap between the lower interlock flange and the rearward facing surface, the lower support plates spaced apart from one another so as to define openings therebetween, the lower support plates separating the lower interlock flange from the rear facing surface so that the lower interlock flange extends substantially parallel to the rear facing surface that it overlies, and
• the at least one lower interlock flange of the panel in the one horizontal course being engageable with the continuous upper interlock flange of the previously mounted panel in the downwardly adjacent horizontal course as an incident to upward movement of the panel in the one horizontal course with respect to the panel in the downwardly adjacent horizontal course for positively securing together the overlying upper and lower marginal edge regions of the respective panels when mounted on the support surface,
• the overlying upper and lower marginal edge regions having detent elements adapted for positive snap action engagement as an incident to engagement of the upper and lower interlock flanges, the detent elements being disposed above the lower edge of the mounted panel in the one horizontal course such that the overlying lower marginal edge region covers and hides the detent elements from viewing from a front side of the mounted panels;
• wherein the detent elements include a first detent element on a rear side of the at least one lower interlock flange and a second detent element on a front side of the upper marginal edge region of the panel opposite the upper interlock flange, one of the detent elements being an elongated protruding nib and the other the detent element being a nib-receiving recess;
• and
• wherein the positive engagement of the detent elements occurs when the protruding nib is seated within the nib-receiving recess.