Standard Door Preparation: Door Knob or Lever

Posted on 10.16.14

The single bore hole is how most doors are commonly prepped. This is the large diameter hole where the lock is mounted and the standardized size of this hole is 2 1/8". Through the edge of the door there is a 1" cross bore that extends from the edge of the door through the bore hole. This cross bore is where the latch is installed.

  • Difficulty: Easy
  • Time: 1 Hour
  • Tools: Hammer, Chisel, Tape Measure, screwdriver, hex key


A door can be prepped for one of 3 different types of latches:


Drive-In Latches

Relax, these are the easiest to install. A door only needs a 1″ cross bore on the edge of the door. Simply slide into the cross bore and tap it into place with a mallet or hammer. (Gently! Go easy!) A ribbed collar around the top helps hold the latch securely when it is driven into the door.

Rounded Corner Faceplate Latches

Rounded corners look sharp and help hold the latch in securely. Round faceplates are 2 1/4″ in height and 1″ wide with about and 1/8″ radius on the corners. Some door shops will prep the door for you to help make installation easier. If your doors are not prepped this way and you want a faceplate, consider locks with square corner faceplates. They are easier to install than round corners. (We’re just sayin’.)

Square Corner Faceplate Latches

Square = Style! If your door is already prepped for drive in latches, you can prep your door for these using a 1″ chisel. Mark the area 1″ wide and 2 1/4″ tall centered on the cross bore and chisel out about 1/8″ depth of material. If your doors are prepped for radius corner faceplates, and you want square corners, you can chisel out the corner.

Standard Door Preparation for Knob/Lever and Deadbolt Combo

Does your door have a door knob and a deadbolt? If so, it should have two sets of bore holes and cross bores stacked on top of each other at 5 1/2″ from center to center. It should have the exact preparation for the deadbolt, as the knob below with a 2 1/8″ diameter bore hole and 1″ cross bore.
In general, deadbolts generally do not have a drive in latch. These doors need to be prepped for either a rounded corner or square corner faceplate latch. Some doors are prepped for a knob with a drive in latch, while the deadbolt hole is prepped for a faceplate. Latches with attached faceplates seem to hold up best under constant day-to-day use.

What we generally ship

To make things easier for you, we generally ship round corner faceplate latches as standard. However, we are more than happy to accommodate any special requests you may have. Just list what you need in the “special requests” box on the product page and we’ll do our absolute best to fulfill your request!

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