Removing the Door
Remove the door from the jamb by removing the screws from the hinges or tapping the hinge pins out with a nail set and hammer.
Remove the casing with a thin flat bar, sometimes called a glazing bar. Be careful not to mar the casing or jamb. A wood shim works well to pry against.
Cut the nails holding the jamb to the wall with a reciprocating saw.
Remove the nails in the jamb and casing by pulling them out from the back with a locking pliers.
Set the door and jamb in a safe place until you are ready to install it in the new opening. It is a good idea to cover the door and jamb to protect it from becoming beat up during the construction stage.
Installing the Door in the New Opening
Mark the location of the hinges on the wall stud.
Nail three sets of shims on the stud at the hinge locations. At the location of the bottom hinge, nail two shims to the wall with 3d finish nails. Adjust or add shims so that the jamb will sit centered in the opening. Hold your 6-foot level against the bottom hinge and place two shims at the location of the top hinge. Adjust the shims until the level shows plumb and nail the shims to the stud. Holding your level against the shims, slip in two shims at the location of the middle hinge and nail them to the stud also.
Set the door in the opening, slide it against the shims and check the head jamb to see it it is level. If necessary, slide a shim under one leg or the other until the head jamb is level.
Drill two pilot holes at each shim location about 2 inches apart and nail the jamb to the stud with 8d finish nails. Use 10d finish nails if the distance between the jamb and the stud doesn't allow the nail to penetrate the stud by at least 1 inch. Use finish nails that are not hardened steel. They are wider and hold much better than the thinner hardened finish nails.
Shim the rest of the jamb, keeping the gap uniform around the door. Install shims at the top and bottom of both sides, 2 inches above and below the latch plate and so that there is no more than about 20 inches between shims. Drill pilot holes and nail the jamb to the studs with 8d finish nails.
Install the casing with finish nails. The size of the finish nails are determined by the thickness of the casing. Generally, you wan at least 1 inch of the nail to penetrate the jamb.
Things You Will Need
- Reciprocating saw
- Thin flat bar
- Nail set
- Locking pliers
- 2-foot level
- 6-foot level
- 3d finish nails
- To determine which size bit to use for the pilot holes, insert the nail into a drill index. Use the bit size that does not allow the nail to slide in to the index.