Abstract: A stair bracket for constructing a staircase is formed from a single strip of sheet metal. One edge of the strip at one end and is upturned to form a flange having a length at least equal to the depth of a stair tread, and the same edge at the other end is downturned into a channel having a length at least equal to the height of a riser, the channel and flange meeting in the middle of the strip. In use the strip is bent at a right angle in the middle at the juncture point with the flange being on the inside of the angle and the channel being on the outside.