Things You'll Need
Cordless drill or screwdriver
Larson is a storm-door manufacturer that offers doors with pet entries already installed. Pet doors are designed for heavy use, but eventually the flap does wear out. Unlike a regular door that we open and close, the flap is dragged along in and out with the pet and thus is subject to wear. As Larson is a well-established company, you can easily order a replacement flap, then install it.
Order the correct replacement flap. Find the registration number of your Larson door before ordering. Measure the size of the flap. Larson doors have two sizes of pet-door flap, either 10-by-15 inches or 14-by-23 inches. Contact Larson directly by phone or online, or go to your dealer with the information for the part needed.
Locate the screw at the top of the pet door, in the frame just above it. Unscrew the pet door flap. Slide the metal bracket holding the flap down and out of the frame.
Slip the flap itself out of the metal bracket by sliding it sideways. Discard the old flap.
Slide the new flap into the bracket by inserting the top edge into the bottom track of the bracket where the pocket for the flap is. Push it through until it is seated evenly at both edges.
Slide the bracket back up into place in the door frame and secure it with the screw.