How to Fix a Door That Won't Latch

A door that won't latch is sure to become a major annoyance. While you may have assumed that your only repair option is to swap the door, the jamb, the hinges and hardware or all of the above, we're here to say that it's likely not that complicated. In fact, you can probably remedy the issue in as little as five minutes. Below, we've explained some potential reasons that your door won't stay shut and provided easy-to-follow steps for fixing a door that won't latch.

Why Won't Your Door Latch?

While a door not latching certainly could be a result of improper installation, it's usually due to foundation settling. This is why old houses often have doors that won't latch. My house is more than 100 years old and every door in it has been modified at least once to account for latching issues.

Identify the Cause

Before you attempt to repair your door's latching problems, take a moment to identify the cause. While nearly all door latching issues boil down to foundation settling or improper installation, they can present themselves in different ways.

Here are the main components that cause a door to not latch:

• Misaligned strike plate. If your door latch isn't aligned with the strike plate properly, it won't latch even if it closes all the way.
• Misaligned door and jamb. If the door and jamb have become misaligned, the door will not shut properly. This can cause the latch to miss the strike plate.
• Loose hinges. Hinges take a lot of abuse after years of opening and closing doors. Failing hinges can cause the door to become misaligned, preventing it from latching when fully closed.

How to Fix a Door That Won't Latch

Once you've identified the underlying cause of your door not latching, you can use the materials list below to identify which tools and supplies you'll need.

Step 1: Measure the Misalignment

Use bright lipstick to mark your door latch, then close the door (Image 1). Take a look at your strike plate and note the position of the lipstick. This will show you how misaligned the latch and the strike plate are (Image 2).

Step 2: Tighten Hinge Screws

Before performing any other repair step, check all hinge screws to ensure they're tight. If the wood is stripped out or the hinges won't tighten, swap the small hinge screws for larger wood screws for a firmer hold.

Step 3: File the Strike Plate

If your latch is only slightly missing the strike plate, which is often the case when a door won't latch, you can simply file away some of the metal to correct the issue.

Step 4: Shim the Hinges

Hinge shims can alter the angle of the door to improve your latch's alignment with the strike plate. To move the latch up, shim the bottom hinge. To move the latch down, shim the top hinge. To move the latch toward the strike plate, shim every hinge.

Pro Tip: No hinge shims on hand? Sometimes a piece of cardboard is all it takes.

Step 5: Move the Strike Plate

If none of the steps above have aligned the latch with the strike plate, you'll likely have to move the strike plate up or down. Sometimes, placing a toothpick in the screw holes, then screwing directly above or below the toothpick is enough to shift the strike plate's position (Image 1). In more severe cases, you'll need to recut the mortise using a sharp chisel and drill new holes for the screws (Image 2).

Step 6: Sand the Door or Jambs

If your door isn't latching because the jamb isn't allowing it to close all the way, you can sand the contact point until the door closes again. If you have to remove a lot of material, there's likely a bigger issue that needs to be addressed.

What to Do if Your Door Still Won't Latch

If your door still won't latch or quickly becomes misaligned after your repairs, there are likely some foundation-settling issues you should address. Spotting and fixing foundation issues early on can save you serious money and prevent further damage to your home. In some cases, it may be a simple fix, such as installing a lally column beneath the doorway.