Leveling a door frame
If you’re installing a door frame and you want the door to operate as it should, then you need to make sure that it’s leveled. A door will sag if the frame isn’t leveled. This will also cause the door to deteriorate as the door will touch the frame.
Leveling the jamb
The first thing you need to do is align the hinge side jamb. Go from the bottom to the top of the jamb. Use wood shims to aid you. These will help you make adjustments to the jamb. In case of a pre-hung door, just remove the slab and this way you will be able to easier maneuver the frame.
Leveling the header
Now, level the header. Use a 2-foot level, but this depends on the size of the door. Also use the shims to make adjustments. Use fasteners to catch the shims.
Leveling the opposite jamb
The opposite jamb can be leveled without the use of a level. There needs to be an even gap between the frame and the door slab. The opening between the frame and slab needs to be consistent. Use the shims to adjust the jab.