What are the steps to adjust an adjustable threshold?
If installed, remove the plastic screw caps on the threshold riser that are located directly under the sweep when the door is closed. There are screws located underneath. Turn screws clockwise to lower the threshold riser (when the sweep is dragging too much when the door opens). Turn screws counter-clockwise to raise the threshold riser (when the sweep is not making good contact/seal with the threshold). Adjusting the threshold riser too high can cause damage to the sweep.
