How to Install a Pre-Hung Door Like A Pro | Step-by-Step Guide

Category - Doors

Skill Level - 2

Pre-hung doors serve as a fundamental component in residential interiors, primarily providing privacy and aiding in the aesthetic cohesion of home spaces. These doors come pre-assembled with a frame and hinges, ensuring a uniform fit and easing the installation process. The reason they are pre-hung is to minimize the complex tasks of door hanging—such as mortising hinges and constructing a frame—which requires precision and can be time-consuming. By purchasing a pre-hung door, homeowners and builders bypass some of the more intricate carpentry work, allowing for a quicker and more efficient installation of a fully functional door that swings smoothly and fits the doorway perfectly. This convenience makes pre-hung doors a popular choice for interior settings where a simple, reliable door solution is needed.

Tools Needed

• 15g nail gun

• Air compressor

• 6ft level

• Air hose

Supplies Needed

• 15g nails

Materials

• Pre-hung door

Quality Check Criteria

• Jamb is plumb on hinge side.

• Margins are consistent around the entire door.

• Door opens and closes correctly without springing (hinge-bound).

• Door is set at the correct height to align seamlessly with the finished flooring.

Process to Install a Pre-Hung Door

1. Preparation of the Opening

• Trim back drywall as necessary around known shim points or across the entire opening if needed to facilitate easier installation.
  

2. Door Placement

• Remove all shipping materials from the pre-hung door.

• Place the door unit in the opening.

• Position ¼” blocks under both jambs of the door to elevate it off the subfloor to the standard height.
  

3. Securing the Hinge Side

• Insert shims a few inches above the top hinge to square the door within the opening. Adjust the quantity and direction of shims as needed to position the door correctly.

• Secure with two nails at this shim point, one on either side of the door stop.

• Place additional shims a few inches above the bottom hinge, adjusting as needed to properly position the jamb.

• Ensure the jamb is plumb between these first two shim points and secure with nails as with the first set.

• Add shims below the top hinge, using the 6ft level to ensure the jamb is straight and plumb before nailing into place.

• Place the final set of shims on the hinge side below the bottom hinge, adjust for plumb and level, and secure.
  

4. Setting the Strike Side

• Begin at the top of the strike side jamb, placing shims a few inches down from the top. Adjust the door margin to approximately ⅛” and ensure the jamb aligns flush with the drywall edges. Nail into place once the correct alignment is achieved.

• At the bottom of the strike side, place shims and adjust until the desired margin of ⅛” is maintained, ensuring the door slab strikes the door stop uniformly at the top and bottom upon closing. Secure with nails.

• Continue to adjust and nail shims around the lockset hole and midway between the lockset and top/bottom of the door to maintain consistent margins.

5. Final Adjustments and Securing the Head Jamb

• Using a pry bar or similar tool, adjust the head jamb near the center. Nail into place using the butterfly method: two nails driven into the same hole at slightly opposite angles for a secure fit. Adjust as necessary to maintain a consistent ⅛” margin.

6. Completion

• Inspect the door to ensure it swings freely and closes flush against the door stop without any gaps.

• Confirm that the jamb is securely shimmed and nailed at 9 points—four on the hinge side and five on the strike side.

This process ensures the door is installed correctly and operates smoothly, aligned with the flooring and functioning properly with consistent margins for a professional finish, ready for casing.