How to Install an Exterior Pre-Hung Door

Pre-hung doors are easy to install, even for do-it-yourself homeowners.

A pre-hung door consists of a door that is already installed within a frame. Rather than installing the door and frame separately, users can install pre-hung doors and frames as a single unit. These units greatly reduce the risk of installation errors, and are designed for do-it-yourself homeowners. To change the look of your home and improve security, consider replacing your existing entrance door with a pre-hung door. You'll find a wide variety of materials, finishes and styles. This project takes just a few hours and requires only basic tools and equipment.

Things You'll Need

• Tape measure
• Level
• Wood shims
• Construction caulk
• Pre-hung door
• 1 3/4-inch nails
• 3-inch deck screws
• Hammer
• Drill
• Fiberglass insulation
• Trim or casing

Instructions

1. Measure the opening for your new door and frame. Choose a pre-hung unit that is about 1 inch smaller than the opening in both width and height. This added space gives you room to install the door, and you can seal it once you complete installation.

2. Check the bottom of the opening with your level to ensure it is flat. If the floor is not level in this area, add wooden shims as you install the door to level out the door and frame.

3. Apply a generous amount of construction caulk to the bottom of the door sill. Slide the pre-hung unit into the opening, bottom first. Center the unit within the opening so there is equal space along both jambs.

4. Add one or two nails to each jamb to hold the unit in place temporarily as you adjust it. Do not hammer these nails all the way in because you will likely need to remove them.

5. Level the door frame. Add wooden shims below the base of the jambs, or between the jambs and the wall framing on either side. Check the frame with your level as you work, and stop adding shims when the unit is completely level and centered within the opening.

6. Drive 3-inch deck screws with your drill into the jamb just below each hinge location. Add 1 3/4-inch nails every 16 inches along both jambs, or as directed in the installation instructions.

7. Install the lockset for your door using the template and instructions provided by the lock manufacturer. Open and close the door to ensure it latches properly before proceeding.

8. Place insulation into the gap around the frame. Fill the space between the jambs and the wall, but do not over-stuff the insulation because that can reduce its effectiveness.

9. Add trim or casing around the frame on both sides of the opening, as desired. To complete the project, caulk the joints where the casing meets the wall on both the interior and exterior sides of the opening.

References

• This Old House: How to Install a Prehung Door
• Reader's Digest: The Family Handyman: How to Replace an Exterior Entry Door