The key to replacing an old doorknob is to buy a new one that fits the existing holes in the door. With this in mind, it pays to remove the old doorknob and take it with you when go to buy the new one. If, for some reason, you can’t do this, gather this information:
• Type of lock—cylindrical, tubular, or rim
• Diameter of the cylinder and latch holes or the size of the rim
• Distance from the edge of the door to the center of the doorknob
• Thickness of the door
• Direction the door opens—inward or outward
Remove the knob by releasing the shank button with a small screwdriver as shown in the illustration a right. Then remove the mounting plate as shown in the bottom illustration—to do this, you usually have to unscrew one or two screws that hold it to the cylinder.
Next, unscrew and remove the latch assembly from the edge of the door. Once you pull out the latch mechanism, you’ll be able to remove the remaining knob and lock cylinder.
To install the new lockset, just reverse the process.
A relatively easy repair for a door that doesn’t lock securely enough is to install a new deadbolt. To do this, you drill two new holes in the door—one in the face for the lock’s body and one in the edge to accommodate the bolt.
Deadbolts are packaged with templates that show the exact placement of holes to ensure a perfect fit.