How to Change a House Door Lock
Why Should You Change Your Locks?
There can be a few reasons why someone might want to change a door lock. You could be focused on security, aesthetics, or both.
If you are making a change with security in mind, then you are likely unsure who else has the key. I recently purchased another house to remodel and sell. In the past, I've had issues with previous owners coming back and using their key to come in. I find that it's just good practice to require a house door lock replacement to protect my investment. You may also have parted ways with a roommate or someone else that had been living with you.
If you are thinking about aesthetics, then you probably are looking to upgrade the style of your home. There are many different style options available, which can range in price from cheap to far too much.
Removing the Existing Door Lock
The first thing you need to do is remove the existing door lock. The handles will come off fairly quickly by removing two screws. Depending on the size of the door handle, you may want to find a long screwdriver to do this, because the angle can be a little tricky. Go easy and try not to strip out the screw heads.
Once the handles are off, then you will need to take out two more screws on the edge (thickness) of the door. This is the part in the picture above where the spring tab protrudes. After you have removed these two screws, you can pull the rest of the lock parts straight out.
You will now be left with a circle hole going through the face of the door to the other side. Also, there will be a hole in the thickness of the door which leads into that same circle cavity.
Installing the New Lock Mechanism
Now open the pack and take out the new lock mechanism. Notice that the spring-loaded tab has a flat side and a slanted side.
You can slide this new lock mechanism back into the hole in the thickness of the door. The flat side of the tab should face the direction that the door moves when it opens. This way, when you close the door, the slanted side will push the tab in until the door is shut, and it'll pop into the hole in the door jamb.
Now find the two shorter, coarse-threaded wood screws in the pack. These will go into the two holes of the locking mechanism.
Installing the New Door Knobs
Now you can install the new door knobs. You'll notice one is just a door knob and the other has some parts sticking out of the back. The knob with the parts sticking out should be put in first. Those parts are going to slide into the locking mechanism that you just installed. You might need to rotate it around a bit to get it to line up, but once you do, it'll slide all the way in so that the new knock is against the face of the door. Now you can put the other knob on the opposite side of the door, again lining up all the parts so that it slides up against the face of the door.
Now you will notice that one knob's base has two holes in it. This side should be facing into the house when the door is closed. If not, then change it around so that they do. If you leave the screw facing out, then someone could just remove them and easily enter your house.
The new longer, fine-threaded screws are in the new pack. It can be a little tricky to line them up through the door, but after a bit of feeling around you'll find it. Tighten these screws up.
Adding the Final Touches
Especially if you are making this change for aesthetic reasons, you are going to want to change the strike plate. This is the metal flat plate with a hole in the middle that the spring-loaded tab will pop into when the door is closed. If the new lock mechanism fits into the existing strike plate, then you don't functionally have to change it. If the new lockset is a different color or finish and you want it to match, then you have one more step.
Remove the two screws in the existing strike plate and pull it off. In the pack, you'll find a new strike place and two short, coarse-thread screws (similar to what you used in the thickness of the door for the locking mechanism). Line up your strike place and put the two screws in.
Now you just need to try the door. Open and close it a few times. Make sure when you close it that the spring-loaded tab falls into the strike plate. You can test this by closing the door and then trying to open it without turning the knob. If it opens, then the tab is missing its hole.
You can usually fix this by looking closely as the door is closing, and see if the strike plate is a bit high or low. If it needs adjustment you can place a nail set on the edge of the opening of the strike plate and tap it a few times in the direction you need. Try the door again. Repeat this until the door stays closed when you try to open it without turning the knob.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.