As your doors age, you may need to make adjustments to the strike plates. Weather and humidity may cause the door and the wooden jamb to alter size and not close properly, or a door may be damaged or sag over time.
Self-adjusting strike plates are a recent development in door hardware. They help prevent misaligned locks and latches, and they cut down on home invasions and door kick-ins—a common crime. Fixing a strike plate is a relatively simple and easy process and can be completed within a matter of an hour.
Step 1 – Mark Adjustment
Put chalk on the end of the bolt. Close the door and note where the mark appears on the strike plate. This lets you know which direction you need to adjust the plate and how much you need to adjust it.
Step 2 – Remove Strike Plate
Unscrew the strike plate. Start with the top screw, then remove the bottom screw. Measure from the strike plate how far to adjust the opening and mark the point on the doorjamb.
Step 3 – Trim the Hole
If needed, make a new mortise for the strike plate. Ream out the hole so that the bolt fits properly, using your mark transferred from the strike plate as a guide. If needed, use a utility knife or sandpaper to smooth the opening.
Step 4 – Fill Old Holes
If there are unused holes which will be left exposed when you reposition the strike plate, fill them with wood putty, allow it to dry, then sand them down.
Step 5 – Check Fit
Tape the strike plate into place. Remove the bolt from the door latch and try to close the door. Be sure that the door closes smoothly and doesn’t catch on the strike plate. If it does, readjust the mortise under the strike plate.
Step 6 –Align Strike Plate
Keep the temporary tape on the strike plate. Replace the bolt into the latch, then close the door and be sure that the bolt fits properly into the center of the hole. If it’s a close fit, another weather change will likely cause it to become misaligned again, so adjust the plate and the size of the hole so that the bolt hits near the center.
If it is still misaligned, use the chalk method again to mark the plate and see where the problem is. Use a round file, utility knife, or drill to ream the hole further until the bolt hits the center of the hole.
Step 7 – Install the Strike Plate
Once you have made all necessary adjustments, open the door. Install the screws into the strike plate, starting with the bottom screw. Don’t tighten the screw completely. Then install the top screw. After both are installed, tighten them down.
Open and close the door several times to be sure that everything is aligned properly.
Although a strike plate may need periodic readjustment and realignment, it is an integral part of a door lock assembly.