Stair of tread and riser joins these by metal or plastics T-profile rail using profile flange and upright flange plus tread safety piece integral to profile at tread edge.

摘要

Tread (1) and riser (2) are joined by a T-form rail profile flanged (3,4) to tread (1) and riser (2) so the flange (3) top joins the underside of the tread and the flange (4) is fixed to the longitudinal side of the riser (2). The T-rail flange (3) is joined also to the face (5) and tread edge (6) and part of the flange underside (3) bears on the riser top and also to the riser longside by upright flange (4). The endfaces of the tread and riser (1,2) are bevelled so the tread and rise stand at right angles to one another. The T-rail profile can also form a tread safety piece at the tread edge (6). The T-profile can also be bonded to tread and riser.