Abstract: A deck fastening system includes an underdeck elongated fastening clip. Such clip is in the form of an elongated metallic sheet of a predetermined width. The clip has a profile defined by a fastening flange, and a depending facia projecting at right angles to the fastening flange from the leading edge thereof, which terminates in an intersecting valley. An angularly upwardly-extending track projects from the intersecting valley at the lower end of the depending facia. A washer flange extends outwardly from the leading edge of the angularly-upwardly-extending track.