Floor construction comprising joists provided with level adjusting spacer screws, joists and spacer screws therefor

A building construction for floors, walls or ceilings with a rigid substructure, comprising:

• a plurality of parallel joists;
• and
• at least one covering layer supported by the joists,
• which joists each comprise an elongate, form-stable body with a first side that is flat and faces the covering layer and a second side that faces the substructure, which joist body has threaded, through-running holes, spaced from each other and extending between and perpendicularly to said first and second sides, and load-carrying level-adjusting spacer screws that are screwed into said holes with their anterior screw portions protruding from the joist body on its second side to adjust the first side of the joist body to a desired level and that have a length such that their posterior screw portions, situated inside the joist body to maintain sufficient thread engagement, have a part-length of at least 10 mm whilst said anterior screw portions have a part-length of at least 1 mm to form an air gap, which extends from said second side of the joist body,
• each level-adjusting spacer screw being provided with a central hole, extending from the posterior end of the level-adjusting spacer screw to a location a distance from the anterior end of the level-adjusting spacer screw to form a bottom part with an inner support surface, and the level-adjusting spacer screw being arranged to be anchored to the substructure by means of an attachment element, extending through a central hole in said bottom part,
• an elastic damping body being arranged at the anterior screw portion, which damping body has a central hole and comprises an outer part, arranged to form a spring connection between the level-adjusting spacer screw and the substructure, and an inner part, arranged to be received in said central hole in the level-adjusting spacer screw,
• wherein the inner part of the damping body forms a resilient engagement element for cooperation with said inner support surface of the bottom part, said attachment element being arranged to extend through the central hole of the damping body, and said inner part having a cross-sectional dimension that is greater than the diameter of the central hole of said bottom part.