If you are retrofitting/replacing an existing lock with a 54mm bore hole, no additional door preparation is required. A 10mm hole can be drilled, however, for the optional fixing post for added stability.
For new door installation, you will need to drill a 54mm hole, an optional 10mm fixing hole, along with the hole preparation for the latch/bolt. Refer to our door preparation guide included in the packaging of the Schlage Ease™ lock.