A wall surfacing system for providing a secondary ceiling or wall covering structure adjacent a primary structure. The system provides a plurality of elongated structural support rails, each of these support rails have a coupling web with a bearing surface for attachment to the primary structure, a coupling mechanism, and a stringer portion integrally formed with and connecting the coupling web to the coupling mechanism. A plurality of generally planar surface panels are provided. Each panel has an integral interlocking member configured to mate with the coupling mechanism on the support rail. The elongated support rails are secured to primary structures, thereby extending the surface panels to form an aesthetically pleasing covered surface.