How do I Frame a Door in a Crooked Wall?

Written by nicole byerly
  • Share
  • Tweet
  • Share
  • Pin
  • Email
How do I Frame a Door in a Crooked Wall?
Door frames can be slightly difficult to install in crooked walls, however it is not impossible. (door frame image by Greg Pickens from

In older homes, walls tend to sag or slant over the years. This ageing of the home may become quite the burden when you are considering adding a new door between two rooms. A standard door is typically 30-inches by 78-inches or 36-inches by 78-inches for an exterior entrance door. Homes that are being modified for ADA accessibility typically use 36-inch interior openings as well. It is important to check that the frame you are installing into a crooked wall is perfectly level as working with these walls may deceive what you actually see.

Skill level:
Moderately Challenging

Things you need

  • Door with casing
  • Two packs of shims
  • Hammer
  • Power screwdriver
  • One box 5-inch screws
  • Level
  • Hand saw
  • Four 2x4x8s
  • Tape measure
  • Jigsaw

Show MoreHide


  1. 1

    Measure the size of the door to determine the frame size needed for the door. Cut the door frame opening to 12-inches higher than the door and 4-inches wider than the door.

  2. 2

    Cut two sections of 2x4 to the height needed for the door, and two sections for the width of the door. Cut two additional sections 9-inches long to top the door frame.

  3. 3

    Insert the sides of the frame. Use a power screwdriver to angle two screws into each outer edge along the bottom to anchor the sides to the floor. Place two additional screws every 12-inches along the height of the door, and anchor two additional screws through each top corner. Ensure that each 2x4 is level before screwing.

  4. 4

    Measure and mark in 12-inches from each end of one 2x4 section cut to the width of the door. Attach one 9-inch 2x4 at each of these locations by screwing directly through the top of the 2x4 to form a strong bond.

  5. 5

    Attach the door with 2x4 with the two 9-inch sections to the top of the frame cut out. Apply two screws through to the top of the frame between the previously installed door height 2x4s and the 9-inch sections. Angle two long screws through the top corners of the door width 2x4 to attach it to the 2x4 at each end.

  6. 6

    Attach the remaining door width 2x4 to the frame. Press the section firmly into place and apply two screws through the 2x4 at each 9-inch section. Angle two additional screws at each end to ensure a strong frame.

  7. 7

    Set the door with casing into the frame opening. Position the casing so 1/2-inch sticks out on both the front and back side of the frame. This will leave enough room for drywall to be hung.

  8. 8

    Screw in two additional screw to the top of the door frame remember to leave 1/2-inch sticking out on both the front and back side of the frame.Check the sides of the frame for level. Slight bowing may occur, so if you will want to screw a long screw directly into the centre of a bowing area.

  9. 9

    Determine the slant of the wall. Because the wall is not straight, you will most likely not achieve a perfect 1/2-inch border on both sides of the frame. It is important to ensure the door is straight and properly working rather than worrying about the 1/2-inch border.

  10. 10

    Open and close the door frame. Check the frame on both sides to look for any slopes or sagging that may interfere with opening and closing the door.

  11. 11

    Insert shims into target areas that need to be spaced out farther from the wood frame. Screw in long screws working from the top to the bottom of the frame. Ensure the door is level between each screw before continuing.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.