- Remove the old weatherstripping by pulling it from the joint in the door jamb on pre-hung doors. Pry nailed-down weatherstrip from the face of the jamb with a flat pry-bar and scrape weatherstrip tape off with a razor scraper. Keep a piece of weatherstrip for comparison. Use the same or a similar style for ease of replacement. Replace the weatherstrip on both sides and the top of your door at the same time to ensure a good seal.
- Measure and cut your weatherstrip to length to fit all three sides of your door. Scissors will work for most types, if your has a metal strip, use tin snips to cut it to length.
- Shove the vinyl bead into the groove in a pre-hung jamb, reinstalling it in the reverse of removal. Use a putty knife or other flat, thin blade. Start at the top and work down. Nail metal edged strip to the face of the jamb with a small tack hammer. Use the nails in the strip for best results. Peel the protective layer from the back of adhesive weatherstrip about 6 inches at a time. Stick it down firmly, starting at the top and working in a straight line, keeping it against the door stop molding.
- Remove the screws, using a cordless drill, and pry the threshold from the bottom of the door frame with a pry bar. Keep the old threshold for use as a template. Make sure your new threshold is the same height and width and at least as long as the original before marking or cutting.
- Set the old threshold on top of the new and mark around it as a pattern. Cut the new threshold along the pattern lines with a jigsaw. File off any rough edges on aluminum thresholds before installing.
- Run a bead of 100 percent silicone caulking around the outside edge of the threshold's bottom and set it into the bottom of the door frame. Tap it into place with a rubber mallet and drive one 3-inch treated deck screw through each hole in the top of the threshold to pull it firmly to the sill below.