How to Replace the Adjustable Threshold on an Exterior Door

Look along the old threshold's surface for screws securing it in place. You may need to peel off screw covers to locate the screw heads. Back out these screws with a drill and Phillips driving bit. If you don't see screws, insert a pry bar underneath the threshold, and pry it off the floor. It may be necessary to cut the threshold in half with a hacksaw. Take care not to damage the floor or the old threshold's side edges.

Measure the door opening width. Do not include the door stops in this measurement. Transfer this measurement to the new adjustable threshold. Cut the threshold's metal surface with a hacksaw, and trim off the bottom vinyl lining with a utility knife.

File the adjustable threshold's cut edge with a metal file. Lay the old threshold over the new threshold. Trace along the old threshold's side edges to transfer any contouring onto the new threshold.

Cut along the traced contours on the new threshold with a hacksaw or tin snips. Test fit the new threshold in the door opening. Make any necessary adjustments until it fits snugly against both side jambs. Attempt to open and close the door. Use a Phillips screwdriver to turn the adjustment screws to either raise or lower the threshold until the door operates smoothly.

Drill 1/8-inch pilot holes through the threshold's screw holes. Drive one of the supplied screws through each screw hole. Push a supplied screw cover over each screw head.