Abstract: The present invention relates to a temporary rail structure that includes a series of vertical posts that are interconnected by horizontally extending side rails. Each post is designed to clamp around the top portion of a band that extends around floor joist that support a sub-floor thereabove. Around the entire floor structure is formed a series of spaced apart openings, each opening cut in the sub-floor adjacent the inside of the band. Each temporary post includes a U-shaped yoke that includes one leg that is inserted downwardly through the opening formed in the sub-floor such that this leg extends adjacent the inside of the band. A screw-type tightener is secured to another leg of the yoke and is screwed from the outside so as to tighten down on the band.