Mechanical locking system for panels and method of installing same

A panel system, comprising a plurality of rectangular panels with long and short edges which are mechanically connectable to each other at a vertical joint plane along an uppermost part of at least one pair of adjacent edges, said panels each being provided with a tongue and tongue groove formed in one piece with the panels for mechanically locking together said adjacent edges at right angles to the principal plane of the panels, thereby forming a vertical mechanical connection between the panels, said panels being provided with a first locking element at one first edge formed in one piece with the panel and a locking groove at an opposite second edge, the locking groove being open towards a rear side or a front side of the panels,

• each panel being provided with a second locking element, formed of a separate material and connected to the locking groove,
• the first and second locking elements form a mechanical connection where a first locking element surface cooperates with a second locking element surface locking the panels to each other horizontally parallel to the principal plane and at right angles to the adjacent edges, wherein the first and second locking element surfaces are located at a distance outside of the vertical joint plane relative to the edge having the tongue groove, and
• the second locking element is flexible and resilient such that two panel are adapted to be mechanically joined by displacement of said two panels horizontally towards each other while at least a part of the second locking element at said second edge is resiliently displaced vertically, until said adjacent edges of the two panels are brought into engagement with each other horizontally and the second locking element at said second edge is displaced towards its initial position against the first locking element at the first edge.