Opening and closing a door is a mindless task, and it’s something you don’t worry about going wrong until an issue pops up. You might ignore the problem for a while, but, beyond being annoying, a door that won’t latch compromises the safety of your home.
There are a few issues that can cause a door not to latch, usually related to misalignment in the door frame or parts that do not match up. Before you start making changes, you should take the time to evaluate the position of your door and latch parts.
In this article we explain how the door’s latch system works and how you use this knowledge to diagnose the issue. We will explain what fixes are appropriate for which problems and how to make sure it does not happen again.
How to Fix a Door That Won’t Latch?
Door Latch System Basics
Your door relies on a few parts for a proper latch, including:
- Hinges to hold the door at the proper angle and prevent drag
- The strike plate hole in the door jamb
- The metal strike plate fastened over that
- The latch bolt in the door attached to your knob
For the door to latch properly, the latch bolt must depress on the angled part of the strike plate and slide across until it can decompress completely in the strike plate hole. Anything that interferes with the process should be addressed to prevent uneven wear on your system and ensure your door latches every time.
Identifying Why Your Door Won’t Latch
There are several components in your door and latch system that can cause it to not work properly. Common issues include:
- Slight misalignment between the latch and strike plate over time
- A strike plate installed too low or too high
- Loose hinges
To identify the issue, close your door completely and try to look around it for any signs of misalignment. Check how the latch locks into your strike plate, and consider how the door sits in the frame.
The first thing to consider is sagging door hinges. This happens to both the top hinge and bottom hinge over time, although abusing your door by slamming or kicking it can accelerate the process.
Make sure your hinges are properly tightened, then check to see if the issue persists.
If hinges are the culprit, you will have improper alignment in the door frame. The top edge of the door may slant to either side, or the bottom edge may drag on the ground.
Unless the hinge is completely broken, you can fix this issue with longer screws or a shim on the affected hinge side.
Sometimes a strike plate is not installed correctly or small foundation shifts cause it to become slightly misaligned. You may notice wear on your strike plate hinting at whether the latch sits too high or too low.
A lipstick test can help you diagnose the issue if you’re having trouble.
Pick up a cheap tube of lipstick (bright red works best), mark your latch, then attach making tape to your strike plate.
When you shut the door, the lipstick will mark where the latch meets the strike plate so you can determine whether it is too high or too low.
A misalignment greater than ⅛ inch means you need to move your strike plate.
Quick Fixes for a Door That Won’t Latch
Depending on your issue, quick fixes for a door that won’t latch include:
- Using longer screws to tighten sagging hinges
- Shimming a hinge in a slightly misaligned door
- Pushing the strike plate down without removing it
- Shaving some metal from a strike plate that’s barely off
These don’t require complete relocation of parts, although some of these fixes are easier if you have another party to hold the door.
Using Longer Screws
One of the simplest fixes for a sagging door is replacing one of the hinge screws with a longer 3 inch screw. This will pull the door in better on the hinge side and allow the latch to sit snug in its strike plate hole.
For a latch that sits too low in the hole, replace one screw in the top hinge. If the door latch sits too high, replace one screw on the bottom hinge to anchor the bottom of the door better.
A Shim Under Your Hinge
If you’re renting or in an older home, you may not have the freedom to fix the door frame as needed. Shimming the hinge can compensate for any misalignment issues due to this.
Cut a piece of cardboard the size of your hinge plate, then remove your hinge screws (on the top hinge when the door needs to be lowered and the bottom hinge when the door needs to be raised).
Place the cardboard on top of the screw holes, align the hinge plate, and fasten the screws. They will pierce the cardboard easily, and this should adjust the door enough for the latch properly.
You can add another piece of cardboard or use thicker cardboard if you need a more drastic change.
Pushing Strike Plate Down
Sometimes you can push a strike plate down without removing it, but only do this for slight alignment issues (only about ⅛ inch or so).
Point a chisel at the lower lip of your strike plate, then tape it gently with a hammer to push the plate down. When you believe you’ve moved it far enough, check the latch clearance.
If the problem persists, you need to relocate the latch plate. Do not push it any further than ⅛ inch.
Shaving Some Metal From the Strike Plate
Shaving metal from the strike plate is another quick fix to consider if you tighten the hinges and nothing changes, but you should only consider it if the difference is too slight to merit realignment.
If you have enough room, you can use friction and a metal file to shave metal from the strike plate without removing it. If not, remove the plate and shave the metal down until you have enough clearance for your latch.
Take care not to shave too much off the strike plate; this compromises the integrity of an important part of your household security.
How to Relocate Strike Plate to Fix a Door That Won’t Latch
While the aforementioned fixes may work for slight issues, you need to relocate the strike plate for greater alignment problems. If the issue has been going on for a while, you may also need to replace a broken or bent strike plate.
To do this you need:
- Phillips head screwdriver
- Utility knife or putty knife
- Hand drill and appropriate bit
- Pencil or other writing utensil
- Hammer and a pinhole nail
- Possibly toothpicks, superglue, and/or wood filler
Luckily, relocating the strike plate is one of the most accurate ways to fix this problem.
Step 1: Removing Strike Plate and Marking Your New Location
Remove the screws and your old strike plate, then mark the new position. Take care not to overlap the latch hole with old screw holes, and try to keep the move as minimal as possible.
Use a pencil to mark the bottom edge of the strike plate at this location as well as the location for your new screw holes.
Step 2: Filling Old Screw Holes and Prepping New Holes
You need to fill the old holes to prevent your screws or drill bit from wandering in the following steps. Use a small amount of wood filler or a glued bundle of toothpicks to fill the old holes.
If using toothpicks, hammer them into the hole and let them set for about 10 minutes before trimming them down.
Work in small steps to prevent cracking or splitting at your new site. Use a pinhole nail to make small holes, then start with a small drill bit. Slowly work up to the size appropriate for your screws.
You may also need to use your metal file or drill to elongate your existing strike plate hole at this point.
Step 3: Cutting New Edge for Strike Plate
Use a utility knife to create a cut large enough to accommodate your chisel. You may also cut along the edge where you want the wood to split.
Fit the chisel into this cut, then tap it with your hammer to loosen the wood. The wood should split along the line, and then you can pull the piece off to make room for your strike plate.
Step 5: Final Installation
Ensure your plate fits flush with your door jamb and that the strike plate hole and screw holes match up.
Once you’ve verified this, insert your screws in the new holes and test out the new location. The latch should lock snugly into place, and you can move on with a feeling of accomplishment and security.
A door that won’t latch will weigh on you until you fix it, but there are several quick and easy ways to address the issue.
Take your time diagnosing the root of the problem, and don’t dance around relocating the strike plate if the issue is big enough (this only makes more work for you in the end).
Comment with any issues you have with your door’s latch, and we will do our best to point you in the right direction.
Monday 2nd of January 2023
Someone adjusted ALL of my Apartment building's street-access doors so the lock won't latch and a key isn't needed to open/enter. (I have notified apartment manager, but they've yet to repair them).
How do you suppose they did this and can it easily be fixed so I can feel safe again ?!
Friday 18th of November 2022
Never knew this before. Thanks!
Thursday 22nd of September 2022
Can you suggest a more durable brand for hinges? Something that could take the weight of heavy wooden doors?
Monday 19th of September 2022
I had a similar issue before. A pair of pliers fixed it. Your list offers even more.
Tuesday 23rd of August 2022
I had a similar fix on my own but this one takes the cake. Thanks!