How Do You Fit the Jamb to Floors of Different Heights?
Cut a 1-ft. long strip of 1/4-in. plywood the same width as your door jamb. Drop it to the high side of the floor, tack it in place, set your scribe and mark the contour of the floor onto the plywood. Remove the plywood, cut the shape with a jigsaw and transfer the shape to the bottom of the jamb. Cut along your mark with a jigsaw. Do this for each side of the door. If your transition is more than 1/2 in., you may need to trim the bottom of the door as well.