How to Repair a Gap Between a Front Door and Its Jamb
- 1). Pry the door casing, or flat vertical trim, away from the wall on the knob side of the door, using a flat pry-bar, to reveal the gap between the jamb and the wall frame.
- 2). Knock out old shims with a cold chisel and hammer. This should leave the jamb fairly loose. Close the door and adjust the bottom of the jamb in until the gap between door and jamb is equal from top to bottom. This gap will range from 1/8 inch to 3/8 inches, but it must be consistent.
- 3). Wedge new shims behind the bottom corner of the jamb to hold it away from the frame at the proper distance. Nail through the jamb and shims into the frame behind. Add shims and nail through the jamb just below the knob and top hinge.
- 4). Check the door for proper operation and add more shims, if needed. Cut any protruding shims with a utility knife, by scoring them along the face of the jamb. Break them off with pliers.
- 5). Pull the old nails out through the back of the casing with locking pliers to prevent damage to the face of the trim. Realign the door casing with the jamb and the top piece of casing and nail in place using finish nails every 10 to 12 inches. Fill the nail holes with painter's caulk for painted finishes or wood filler for stained. Complete the repair with a coat of paint or stain in a matching color.
- 6). Apply a strip of 1/4-inch weatherstrip to the inside face of the door stop to ensure a weather tight seal. Remove the wax paper backing from the adhesive strip and start at the top corner, and press the weather strip firmly against the door stop as you move down, realigning the weatherstrip as needed to make a straight line. Cut off any excess with a utility knife.
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