How to Install Inside Doors
- 1). Unwrap the pre-hung door and gather all tools. Place the pre-hung door into the rough door opening on the wall. Check for clearance around all edges and make sure that the door jamb is thick enough to accommodate the thickness of the wall. Make sure that the door is centered in the opening before continuing.
- 2). Ensure the door is straight using the level and use the shims to hold the door in position. Select the size of shim that is needed, and insert the shim between the outside of the door jamb and the wall. Lightly tap the shim into place with the hammer until it is secure.
- 3). Nail the jamb into place starting on the hinge side. Center the nails between the hinge locations, and nail completely through the jamb and shims into the door frame. Nail the opposite side of the jamb in place, avoiding the areas where the hardware will be attached. Nail the front and bottom jambs into place, starting in the center and working your way out.
- 4). Saw off the ends of any shims that protrude beyond the wall so that the shims are flush with the door jamb.
- 5). Inspect the door. Make sure it is level inside of the jamb and check the hinges. Tighten the hinge screws if necessary.
- 6). Screw the locking hardware into place on the door jamb and install the doorknob according to the packaging instructions.
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