Setting the Top TreadOnce the top riser is set, you can set the top tread on the platform. This tread does not need to be 11 inches because it is part of the flat surface of the platform. Spread some mortar on the platform and set the bricks with a quarter inch overhang over the riser below. You don't want the overhang to be too long or you risk the bricks crumbling and breaking. Maintain half inch joints and work your way around the platform. Check that the bricks are level left to right, and pitch slightly away from the house (figure H).