How to Fix a Sagging Door

Wooden Door

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Project Overview
  • Working Time: 30 mins
  • Total Time: 15 - 45 mins
  • Skill Level: Beginner
  • Estimated Cost: $5 to $10

Sagging doors are common in older houses. It's almost a rite of passage that eventually the doors, along with the foundation and other elements, will sag. Newer homes can have sagging doors, too, if the door wasn't properly installed or if too much weight was placed on the door.

The good news is that fixing sagging doors is easy, fast, and inexpensive. With just a few tools, you'll have the door re-aligned and swinging freely in no time at all.

What Causes Sagging Doors?

A sagging door is usually one that tilts at an angle, from the hinge side. Looking at the door straight on, the top of the door (on the doorknob side) extends beyond the bottom of the door.

Often, the sag is not visible when the door is open. But opening and closing the door causes the door to scrape the door jamb at the top. Doors with pronounced sags can stick to the point where it becomes difficult to open or close the door.

The source of the problem can usually be traced to the top hinge. Screws in the top hinge loosen or begin to pull straight out in a way that isn't mirrored in the bottom hinge.

Hinges are durable fixtures that can last for decades. But in some cases, the hinge leaves or the hinge pin may begin to wear out. Loose hinges may need new pins or may need to be replaced entirely.

If there is paint under the door hinges, this usually throws the door out of alignment. Paint or stain may have been added to the mortise in the door or the door jamb. The door may have been removed for painting and the entire door edge or jamb was painted or stained. Extra layers of paint or stain act like spacers to push the door out of alignment.

What You'll Need

Equipment / Tools

  • Cordless drill with driver bits
  • Five-in-one tool or wood chisel
  • Hammer
  • Scrap piece of wood
  • Sander
  • Metal file or sandpaper

Materials

  • 3 x 1-1/2-inch screws
  • 1 x 3-inch screw
  • 3 coarse-thread screws
  • Door hinge

Instructions

  1. Tighten Existing Hinge Screws

    With the cordless drill or manual screwdriver, tighten all of the screws in the top hinge by turning clockwise. Be sure to tighten screws on both the door side and on the jamb side. Often, this repair alone is enough to fix sagging doors.

    Do not overtighten the screws as this might strip out the wood. This will only make the screws looser.

  2. Remove Hinge Spacers

    Sometimes, a previous owner may have added a spacer to the top hinge. The spacer may be a thin strip of cardboard inserted under either hinge leaf and likely was designed to cause the door to fit into the frame more tightly.

    If a hinge spacer is visible, remove the hinge by turning out the screws. Slip out the spacer, discard it, and replace the hinge. Try the door again.

  3. Add New Hinge Screws

    Standard hinge screws are 1-inch long. If you tighten the existing screws and they keep rotating, you will need to increase the length of the screws. Use 1 1/2-inch screws. You may also try switching out the existing screws for screws with a coarser thread.

  4. Replace Hinge Screw With 3-Inch Screw

    A highly effective way to fix a sagging door is to replace one of the top-hinge screws with a 3-inch long screw. This serves not only to pull the hinge closer to the door jamb, but it draws the entire door frame closer to the underlying stud.

    1. Remove all three screws from the hinge on the side of the door jamb.
    2. With the cordless drill, drive a 3-inch screw into the center hole of the hinge.
    3. Replace the other two screws in the top and bottom positions.
  5. Remove Paint From Under Hinge

    Similar to removing spacers from under the hinge, remove the hinge, then use the sharp blade of a five-in-one tool or a wood chisel to scrape away accumulated paint in the mortises or from the door jamb.

    The goal is to remove all paint and bring the edge of the door back down to bare wood, but not to remove too much wood. Do not use a utility knife or razor blade.

    Sharpen Scraping Tool

    Whether you use a wood chisel or a five-in-one tool, it most likely will need to be sharpened before scraping the jamb or mortises. Set the tool in a vise and use a metal file to sharpen the blade. Or use a strip of sandpaper placed flat on a table, grit side up. Run the blade forward over the sandpaper until sharp but not razor-sharp.

  6. Tighten Top of Door Jamb

    If you have tightened the door to the door jamb yet the door still sticks, drive a 3-inch screw to the top of the door jamb on the latch side.

  7. Bend Back Top Hinge

    Remove the door from its hinges by removing the pins, then sliding the door off. Gently tap the three knuckles (the barrel-shaped portion that holds the pin) with a hammer. Buffer the hammer by placing a piece of scrap wood between the hammer and the knuckles.

    Warning

    Do not bend the knuckles more than 1/16-inch. Otherwise, you risk misaligning the door with its other hinges.

  8. Sand Top Edge of Door

    Sand the top edge of the door by hand or with an orbital sander. The sticking area will usually identify itself with prominent scuff marks.

    Sand carefully. Sand the door a little, then try closing the door. Repeat until the door is able to open and close without contacting the jamb.

  9. Sand Top Section of Door Jamb

    Much like sanding the top edge of the door, sand the top of the door jamb where the door sticks. Essentially, the door's tilt remains, and the door jamb adapts to this tilt.

  10. Install New Hinge

    Some very old hinges will naturally loosen over time, as metal rubs against metal and wears away. If a pin rattles or moves when it is in place, it's likely the hinge is not as tight as it could be.

    You may be able to replace the pin with a new one. If you are able to find a single hinge that matches the door's other hinges, replace the hinge entirely. Or you may decide to replace all three hinges at the same time.