Fixing a Latch That Won't Catch: The Strike Plate
Last lesson we did hinges. This one's the strike plate, which is the other half of the equation and honestly the one people mess up more, because they don't know it exists.
Quick refresher on parts. The latch is the little beveled piece that sticks out of the edge of the door. The strike plate is the metal plate on the door frame with the hole in it, the thing the latch is supposed to slide into and catch. If your door swings fine, closes fine, and then just doesn't latch, or you have to lean into it with your shoulder to get that click, this is almost always your problem. Not the door. The strike plate.
How to tell it's the strike plate
Close the door slow, most of the way, and watch where the latch is lining up against the frame. A lot of the time you'll see it clean as day, the latch is hitting metal instead of finding the hole. Sometimes it's hitting an inch too high, sometimes it's catching the edge of the plate instead of sliding in.
Another way to check, put some lipstick or a bit of chalk on the latch itself, close the door like you're trying to latch it, then open it back up and look at the mark it left on the strike plate. Wherever the mark is, that's where the latch is actually landing. Tells you exactly how far off you are and which direction.
This is a super common one and it's almost never that somebody installed the door wrong from scratch. Usually the house has settled a little, or the door's swelled or shrunk with the seasons, and the strike plate just isn't lined up with the latch anymore like it used to be.
Fixing it
A few different ways to go, depending on how far off it is.
If it's off by a little (a sixteenth of an inch, that range): File the hole in the strike plate a bit bigger with a metal file, on the side you need more room. Doesn't take much. Go slow and check the door after every few strokes so you don't overdo it.
If it's off by more than that: Take the strike plate off, two screws, and use a chisel to deepen or reshape the mortise, that's the little recessed pocket the plate sits in. This is basically what I did for Verl, my neighbor. His back door hadn't latched right through two winters, his wife had a bath towel jammed under it to keep the draft out. I planed the bottom edge a touch and then took a chisel to the strike plate mortise, moved it just enough, and it clicked shut like it was new. Twenty minutes on a Saturday. He acted like I'd rebuilt the whole house. I hadn't, I'd moved a piece of metal a quarter inch.
If the plate itself is in the right spot but just needs to move up or down a little: Sometimes you can get away with elongating the screw holes instead of touching the mortise. Loosen the screws, shift the plate up or down within the new slop in the hole, retighten. Quick fix, doesn't always work depending on how far off you are, but worth trying first because it's the least destructive option.
Chisel work: keep your other hand behind the blade, not in front of it. Chisels are sharp and they will go where you push them, including into your palm if you're not paying attention. Doesn't take a lot of force to move wood, so don't lean on it.
The opinion I'll stick by here
Diagnose before you fix. I say this every module because people keep skipping it. A door that won't latch gets people reaching for wood filler, a whole new lockset, sometimes a whole new door, when nine times out of ten it's this plate being a hair out of position. Slow down, watch where the latch actually lands, and fix that specific thing.
The one I'll admit to
I'll tell on myself here. My own bedroom window rattled every time the wind picked up, and it did that for about a year before I did anything about it. I complained about that window constantly. Told everybody who'd listen how annoying it was. Turned out the sash lock, the little latch that pulls the two window halves together, wasn't doing anything. Some part had worn or bent and it just wasn't engaging. Fifteen dollar part at the hardware store. Fifteen minutes to swap it. A year of listening to that thing rattle because I never actually looked at what was wrong, I just lived with it and grumbled.
That's the whole lesson, honestly. Same thing as the strike plate. The fix is usually small and cheap. The hard part is making yourself stop and actually look instead of just tolerating it or assuming it's a bigger job than it is.
Before next time
If you've got a door in your house that doesn't latch clean, do the chalk test on it before our next session. Just see where the latch is actually hitting. No need to fix it yet, I want to hear what people find.