Instructions for Hanging a Pre-Hung Door

Raise the door and slide it into the opening. Check the top of the door frame to see if it is level. If not, raise up the end that is lower and put shims under until it is level. Remove the door and nail the shims to the floor so that they do not slip.

Put the door back in place and push the hinge side up against the side of the opening. Check it with a level to see if it is square. If not, slide shims in on top of each other until you get the side of the frame square. Remove the door again and tack these into place, then put the door back. Repeat with the top and other side of the door.

Open the door to ensure that it doesn't drag on the ground. Remove it and trim or sand the bottom if it is dragging. Use sandpaper for slight adjustments or a circular saw for bigger cuts.

Nail the sides of the frame into the rough opening through the shims once it is squared up.

Unscrew the hinge screws one at a time from the hinge, and replace them with longer screws. The screws in the hinges go only into the frame. Use screws long enough to go through the frame and into the rough opening. This will keep the frame from shifting over time and sagging.