What is a kerf in a door?

A kerf in a door refers to the groove or cut made in the edge of the door, typically for the purpose of accommodating a weatherstrip or a sealing mechanism. This cut allows for a snug fit when the door is closed, helping to improve energy efficiency and reduce drafts. Kerfs can also be used in the installation of hinges or locks, ensuring that these hardware components fit securely. Properly designed kerfs contribute to the overall performance and durability of the door.