You may have come across the term Kerf while wandering through the aisles of your local hardware store. Kerf weatherstripping refers to a type of weather strip that is installed in a door kerf, which is a  groove or slot in the door frame or jamb designed to accommodate the weatherstripping material.

Typically, Kerf weatherstripping  is made of flexible material such as foam or rubber. It is designed to be installed around the perimeter of the door frame so that it creates a tight seal when the door is closed. The goal is to  improve energy efficiency and comfort by keeping  out air drafts, water, dust and noise.

To install kerf weatherstripping, first remove any existing weatherstripping that you want to replace. The new material is then inserted into the door kerf, where it is held in place by friction.

Kerf weatherstripping is commonly used in interior and exterior doors in residential and commercial buildings. It is available in various profiles, colors and sizes to suit different door configurations and can be chosen based on the desired level of sealing and insulation.

If you have older home, its very likely that your door frame will not have a pre-existing kerf. Alternative weatherstripping options such as door weatherstrip kit can be used instead.