How to Adjust Metal Thresholds

Close the door where the threshold is located.

Shine a flashlight under the door. Check on the opposite side of the door to see whether you can see any light passing through between the threshold and the bottom of the door.

Note which side of the threshold you see any light passing through, indicating that the threshold is adjusted too low. Open the door. Check the top surface of the threshold for wear marks, indicating that the threshold is possibly adjusted too high. Open and close the door slowly. Listen for the rubber weather stripping on the bottom of the door rubbing against the threshold. Note that if you hear nothing, the threshold may be adjusted too low.

Locate the adjustment screw heads on top of the threshold. Turn the adjustment screw closest to where the threshold needs to be raised or lowered with a Phillips screwdriver. Turn the screw in a clockwise direction to raise the threshold and in a counterclockwise direction to lower the threshold.

Open and close the door. Note that there should be a slight resistance when the weather stripping on the underside of the door rubs across the threshold. Know that a door that opens or closes too easily may indicate the threshold still needs to be adjusted upward whereas a door that is hard to open or close may indicate the threshold needs to be lowered.