Prevent Your Doorknob From Locking You Out

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Introduction: Prevent Your Doorknob From Locking You Out

About: The only thing I enjoy more than building things is taking things apart. You don't truly own something until you've voided the warranty. Profile image by Achim Grochowski (via wikimedia project)

After I moved into my current house, I noticed that the doorknob on my back door had a very annoying "feature". The doorknob on the interior side would turn and open the door whether the knob was locked or unlocked. My family has always had the sort of knobs that won't turn at all when the door is locked, and has grown accustomed to interpreting a turning doorknob as one that will not lock behind them. Within a few short months, various members of my family have succeeded in locking themselves out of the house using this new type of knob. Instead of completely replacing the knobs (zero fun) or hiding a spare key outside (big security hole), I set out to discover how these knobs work and how to modify them to be more user-friendly.

The doorknob set in question has an interior knob with a rotating tab (see photo) and an exterior knob with a keyhole. The door's primary security device is a deadbolt, and we never intentionally lock the handle. Unfortunately, the lock tab does get turned by accident, usually from being bumped or getting caught on someone's clothing. I figured that I could solve the problem by preventing anyone from unknowingly locking the door by accidentally bumping the tab.

A Note About Safety: This feature is viewed by many as a safety issue. In the event of, say, a house fire, you can quickly exit without needing to fumble around and unlock the door. This modification does not impact the safety aspect of this model of knob; you can still open the door from the inside without needing to unlock it. You should probably not make this modification on knobs that have keyholes on both knobs.

Step 1: Remove Doorknob

The doorknob will be held to the door by two screws. Remove these screws and the doorknob should pull apart into three pieces: the interior knob, the exterior knob, and the latch mechanism that sits inside the door. Take a good look at how the knobs fit together when removing them, since you'll need to put everything back together later.

Try to keep a hand on both knobs when removing the final screw. Without the screws in place, they tend to fall out of the door and can get scratched or dented if they hit hard pavement.

Step 2: Modify Lock Mechanism

The locking mechanism is part of the exterior knob. That knob has a square shaft attached to it, which causes the latch to retract when the knob is turned. A long, flat rod sits inside the shaft and protrudes from it several inches. This rod is permanently attached to the locking mechanism and when the doorknob is fully assembled, the far end of it will connect to the rotating tab on the interior knob. Turning the tab will rotate this rod, thereby engaging or disengaging the lock.

This flat rod is the source of all of our problems. Cut off the protruding end of the rod using a rotary tool or a hacksaw. Cut the rod close to the end of the shaft, but be careful not to cut the shaft itself. By cutting the rod, you are severing the rotating tab's connection to the lock.

Step 3: Re-assemble the Doorknob

Carefully put the doorknob back together. This generally involves attaching the exterior doorknob first - sliding it through the holes in the latch mechanism - and then re-connecting the interior knob. Replace the two screws, then check that both handles still turn and engage the latch.

You will notice one key difference with your modified doorknob: the rotating tab on the interior knob now spins freely. Cutting the rod severed the tab's connection to the lock mechanism, and the tab no longer serves any function. The only way to lock or unlock the knob is by using a key on the exterior knob, ensuring that both you and your key are on the same side of the door. There are still some rather elaborate scenarios where you can lock yourself out, but they're far less likely to occur since they all require you to knowingly and intentionally lock the door.

You lose the ability to lock the knob from inside the house, so this shouldn't be done if the knob is your only way to lock the door (knob locks aren't very secure so if this is your situation, you *really* need to consider adding a deadbolt). We use a separate deadbolt for security, not the knob lock, so it wasn't a factor for us. Making this one simple change has completely halted our pattern of people locking themselves in the back yard, without having to re-knob the house or introduce any new security problems.

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    7 Comments

    0
    DawnP85
    DawnP85

    Question 2 years ago on Step 3

    Thank you so much! You made that sound like a piece of cake! My evil door knob is a push button model. It sure sounds like it would be the same method to disable the automatic lock on it as well though. Does that seem right to you?

    0
    sparkchaser
    sparkchaser

    Answer 1 year ago

    Sorry for the (really) late response. On my lock, the locking mechanism was on the keyed side of the knob, and the long metal rod connected that to the twist tab on the other side. Push-button locks (also called "privacy knobs") generally don't have anything on the other side, so your mechanism will likely be entirely inside the knob with the button.

    What I would do for one of those is to take off the knob and watch the mechanism move as it was locked and unlocked. You want to prevent the lock from engaging, perhaps by cutting a mechanical link, jamming the mechanism to prevent it from moving, or even by gluing the push button in place. If the other side has a little hole for unlocking the knob, you might also be able to jam that mechanism in the "unlock" state, which should prevent the lock from latching when the button is pressed.

    0
    loricupp1962
    loricupp1962

    Question 1 year ago on Step 3

    Lock has no screws on it. No tab to lock. Locks by itself if we close to go on balcony. Also 2 yr grandson loves to close the door . How can we disengage. And is this even legal ? We have only lived in this apartment a week and have already been locked on balcony more than once. Thankfully there has been someone inside to let us in .

    15928575622751933395575752889701.jpg
    0
    sparkchaser
    sparkchaser

    Answer 1 year ago

    If it's keyed on both sides then the lock mechanism is much harder to bypass. For those knobs, it's usually easier to leave a key in the lock and tape a note at eye level to remind you to unlock it on your way out.

    The screws are always on the indoor side of the knob. If they aren't visible, then they're hidden underneath the round metal shroud. If you look closely, there's probably a small hole on the shaft on the underside of the knob. Pressing something into the hole while pulling the knob will remove the knob from the shaft. After that, you should be able to gently pry the shroud off with a screwdriver and access the screws underneath.

    I can't tell how your knob works from a photo alone, but you can usually get a sense for how it works by watching how the internal parts move when you turn the knob, activate the lock, etc. If there's no obvious way to disable the lock, I recommend just getting a new doorknob that works the way you want it to work.

    A word of caution: your knob has a keyhole and there's no deadbolt visible in your photo. If that knob is the only way to lock that door, then its behavior might be a "safety feature" required by your local building codes. Make sure your replacement knob provides adequate security and meets all local rules.

    0
    Swansong
    Swansong

    4 years ago

    Great fix, that's really annoying when it won't lock like that!