A flooring of pre-stressed deck construction has an elongate decking (10) extending along the flooring, the decking (10) having an upwardly facing asymmetrically profiled channel formation (11) whereby the neutral axis is above a central horizontal plane. A tension rod (40) extends between stressing brackets (20) secured to each end of the decking (10) and is located below the neutral axis of the decking (10) along the length of the decking (10). Each stressing bracket (20) is secured to upwardly extending sidewalls (13) of the channel (11) above the tension rod (40). The decking (10) is attached to the girder framework (44) of a building. Since the tension rod (40) is below the neutral axis of the decking (10), the bending stress applied to the decking (10) is positive, causing upward arching of the decking (10). This is stress relieved when the concrete flooring (53) is applied to the decking (10). Since the attachment of the stressing brackets (20) to the decking (10) is above the tension rod (40), there is no negative bending stress applied to the ends of the decking (10). In fact, the positive bending stress applied is enhanced by this configuration.