Door Won't Latch? Fix It Tonight
- 7 parts and tools
A door that will not latch is a security problem and a sleep problem, because it swings open on its own or will not stay shut. Most latching failures tonight come from a strike plate that moved, a door that sagged, or paint and swelling that changed the fit, and all of those are fixable with basic tools. Start by watching exactly what happens when you close the door, because where the latch misses tells you what moved.
What's probably wrong
A misaligned strike plate is the most common cause. The strike plate is the metal piece on the door frame that the latch clicks into. If the door or the frame shifted even a little, the latch bolt hits the edge of the strike plate instead of sliding into the hole. You can usually see the scratch marks where the bolt has been hitting.
A sagging door is the second suspect. Doors hang from hinges, and over time the top hinge loosens, the screws strip, or the door itself warps slightly. A sagging door drops on the handle side, so the latch sits too low to meet the strike plate. If the door rubs at the bottom or the gap at the top is wider on the handle side, the door has sagged.
Swelling and paint buildup is the third suspect. Humidity makes wood doors swell, and repeated paint jobs add thickness to the door edge and the frame. A door that latched fine in winter and sticks in summer is almost certainly swelling. A door that stopped latching right after painting probably has paint buildup in the latch area.
A faulty latch mechanism is the fourth suspect. The latch bolt itself can wear out, get stuck, or lose its spring. If the bolt does not spring out freely when you turn the handle, or if it sticks halfway, the latch mechanism is the problem, not the alignment.
A foundation or frame shift is the serious cause. If several doors in the house stopped latching at the same time, or if you see new cracks in the walls near the door, the frame itself may have moved. That is a bigger structural question, and it is not a tonight fix.
Fix it tonight
Watch the latch as you close the door slowly. Have someone else watch, or put a small piece of tape on the latch bolt and close the door gently to see where it marks the strike plate. If the bolt hits above the hole, the door has sagged or the plate is low. If it hits below, the opposite. If it hits the edge, the door is shifted sideways. This one observation guides everything else.
Tighten the hinges. Open the door and tighten every hinge screw on the door and the frame side, starting with the top hinge, which carries most of the weight. If a screw spins without tightening, the hole is stripped. Remove the screw, push a wooden golf tee or a few toothpicks coated in wood glue into the hole, let it dry if you can, then drive the screw back in. For tonight, even toothpicks without glue will hold a screw well enough to test the fit.
Adjust the strike plate. If the latch misses the hole by a small amount, loosen the strike plate screws and shift the plate slightly in the direction the latch needs to go. Tighten it and test. If the latch misses by more than the plate can move, you need to enlarge the hole instead. Mark the new position with a pencil, remove the plate, and use a chisel or a rotary tool to extend the mortise in the right direction. Work slowly and test often, because removing wood is easy and adding it back is not.
File the strike plate edge. If the latch just barely catches the edge of the strike plate, a few strokes with a metal file on the edge it hits can be enough. This is a small adjustment for a small misalignment, and it is much faster than moving the plate.
Check for swelling and paint. Run your hand along the door edge and the frame where they meet. If the door rubs in one spot, mark it with a pencil. For paint buildup, scrape or sand the built up area lightly. For swelling, you can sand the rubbing spot lightly tonight, but do not remove a lot of wood, because the door will shrink again when the humidity drops and you will have a drafty gap. A light sanding to get through tonight, plus a plan to address the humidity, is the right approach.
Fix the latch mechanism. If the bolt sticks, spray a small amount of graphite lubricant or silicone spray into the latch and work the handle back and forth. Do not use cooking oil, because it gums up over time. If the bolt still does not spring out freely, the latch assembly is worn. Replacing a latch is a straightforward job: remove the two screws on the door edge, slide the old latch out, slide the new one in, and test it before you put the handles back on.
Check the door closer or hinges on an exterior door. Heavy exterior doors with closers can fail to latch if the closer is adjusted too weakly or the hinges are binding. Adjust the closer speed so the door closes firmly in the last few inches. If the hinges squeak or bind, a drop of lubricant on each hinge pin can help, though a bent hinge pin needs replacing.
Test the door ten times. Open and close it normally ten times in a row. It should latch every time without you pushing, lifting, or slamming it. If it latches nine times and misses once, the alignment is still marginal, and a little more adjustment now saves another night of frustration.
Parts and tools
When to call a pro
Call a pro if several doors stopped latching at the same time, if you see new wall cracks near the door, or if the frame itself looks twisted or out of square. Call a pro if the door is badly warped, if the frame is damaged, or if the door is a fire rated door in a garage or between the house and an attached garage, because fire doors have rules about what can be modified. A handyman can handle most single door alignment jobs, and a structural issue needs a contractor.
What a pro typically costs
These are broad typical ranges, not quotes. A handyman door alignment visit usually runs about 100 to 200 dollars. A latch replacement usually runs about 100 to 200 dollars including parts and labor. Rehanging a door usually runs about 150 to 300 dollars. Frame or structural work varies widely and can run from a few hundred dollars upward depending on what is found.
FAQ
Why does my door latch in winter but not in summer?
Wood swells with humidity. A door that fits in dry winter air can swell just enough in humid summer air to miss the latch or rub the frame. Light sanding at the rub point helps for tonight, and controlling indoor humidity helps long term.
Can I just move the strike plate instead of fixing the sag?
Moving the plate works for a small misalignment, but if the door is sagging because a hinge is loose, the sag will get worse and you will be moving the plate again. Fix the hinge first, then adjust the plate only for whatever small gap remains.
Is a door that will not latch a security risk?
Yes, especially for an exterior door. A door that does not latch is held shut by nothing but friction, and it can be pushed open easily. If you cannot fix an exterior door tonight, secure it another way for the night, such as a secondary lock, a door bar, or a chair under the handle, and fix it properly as soon as possible.