Abstract: An apparatus for retaining and controlling the size of pieces of snow and/or ice accumulating on a roof contains brackets secured to the roof and rails passed between the brackets to form a frame structure. The brackets have slots and/or pockets for fitting rails and enable the rails to be at or below the level of seams on seamed roofs and at a low profile with non-seamed roofs. In addition, the brackets may be attached to the roof without penetrating the roof structure. A method of installing a snow and/or ice retaining apparatus includes lowering the rails into pockets on the brackets, sliding the rails into slots on the brackets, and, optionally, securing the rails with a clip, wedge, or adhesive.