I am doing a large extension and installed 3 piece metal frames upstairs on timber stud work.Now starting to hang 4 panel atherton doors(corinthian) i have noticed that the keepers on the metal door frames are not in line with the horizontal mid rails of the doors, the keepers are approx 1020 from the floor.I just figured it would look better though lower to have them in the middle of the mid rail.Is this a regular occurance? I thought all metal door frames had keepers the same height?I'm not stressing just curious as i will just lift the handles to match frame keepers.Many thaks for any replies stephen