Home safety is one of life’s highest priorities. Because of this, you should be sure that your windows can be securely locked.

Want to know how to install a window lock? I can show you in six easy steps. These steps may seem intricate at first, but with a little know-how and focus, you’ll be safely securing your windows in no time. Read on to hear more about how to install window locks.

1. Identify Your Window

There’s a variety of options to choose from when it comes to window locks. There are multiple important factors to consider before you stroll into a hardware store with your cash. First, you must determine what kind of window you will be installing a lock onto. In most homes, people have what are called double-hung windows with two square elements that slide up and down.

Another style of window you can find in residential buildings is the single-hung window.

Single-hung windows are like double-hung windows because they both consist of a frame with two square elements. The only difference is that the single-hung style only has one piece that slides; the other is fixed in place. Other buildings might have sliding windows, like the ones you might see at a drive-thru restaurant, or casement windows, which use a crank to open partially.

For the sake of this tutorial, I’ll be using the example of a double-hung window. This is probably the style you have at home. For other styles of windows, the steps will be similar. If your window is hung sideways, you’ll just be drilling sideways.

See also: Best Window Manufacturers in the US

2. Choose Your Window Lock

The next decision you must make is which lock to choose. Most windows come with what is called a latch lock.

A latch lock is a two-part mechanism that attaches to both the upper and lower portions of a window, latching them together with a small level that is connected to a curved metal piece.

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This is the lock we will be working together to install because they are one of the most common and most easily installed locks. Other varieties such as swing locks and keys are normal but less common than the latch.

Not only do you have to choose the variety of lock, but you also must choose the style of your lock. Though it may seem like a small detail, it’s important to consider how to coordinate your window locks with the rest of your house.

If you have a house with more metallic accents, consider one like this Satin Nickel lock from Designers Impressions. If you have more of a country feel in your home, opt for one in soft white or brushed metal.

3. Gather Tools

To be able to install a window lock, you will need the right tools.

The most important tool for installing window locks is a drill. You’ll want one with drill bits that correspond to the size and style of mounting screws that come with the locks you just bought.

This Avid Power Cordless Drill is a great option for the DIY-er looking for a reasonably-priced, reliable drill for everyday fixes, and comes with the most important accessories.

Other important tools you will need to gather are a tape measure and a pencil.

A great option for a pencil that you can use for installing windows is a carpenter’s pencil, which is designed for drawing bold lines and dots on wood. This AlwaysSharp Refillable Mechanical Carpenter Pencil is an affordable and reliable choice.

4. Remove Old Locks

If you’re installing window locks, it’s likely that there are already locks in the windows you’re working on. If this is the case, you will have to remove the old locks, which might be broken, worn out, stuck, or just not your style.

To remove the old locks, you’ll need to take the old screws out. Put the corresponding style of the drill bit into the drill and line up with the old screws. Drill the screws out by running the drill in its reverse setting, which will spin the drill bit counterclockwise.

From here, the lock should be easily removable. If it’s stuck to the window, you may need to gently pry it off with a small palette knife. Once you’ve taken the old locks off, you can either throw them away or choose to “upcycle” them.

You may be able to recycle your old window locks – check on the bottom of the locks for the recycling symbol. Another option is to donate them or bring them to a local transfer station.

5. Mark Placements

Now that the old locks have been removed, it’s time to prepare to install the new ones.

If you’re installing a new version of the old lock you just removed, you won’t need to mark and drill new holes – you can simply line the new locks up with the holes from the old screws.

However, if you’re installing a new type of lock, you’ll need to mark and drill new holes into the window, both on the upper and lower sliding portions.

Use this process to mark the lock placements:

  1. First, take your tape measure and your pencil or pen and mark off the exact center of the window. This is where you’ll be placing the lock.
  2. Center the lock exactly in the middle of the window where you made the mark, making sure it bridges the gap between the upper and lower portions.
  3. Poke your pencil or pen through the holes of the lock and make little dots where the screws need to go.

6. Screw in Your Window Locks

It’s finally time to install your window locks. Here’s the process:

  1. Now that you’ve marked off the placements for the new screws, drill holes directly into those spots that correspond to the length and width of the new screws.
  2. Align the entire lock over the holes you just made, and drill the screws in. Keep double-checking that you’ve gotten them in the right spot, and that you’re able to keep the top and bottom parts of the window flush.
  3. Once you’ve completed this much, you’ll want to double-check your work. First, make sure that the screws are tightly installed. There are few things worse than completing a project and realizing later that your work was poorly installed.
  4. Give the screws a couple of extra drills for good measure, making sure not to strip the screw while you do so.
  5. Then, open and close the lock to check its strength. Is it easy to close? Is it a secure fit on the window? It may even be helpful to go outside the window (if it’s accessible from outdoors) and make sure that it’s impossible to enter from there. Then you can rest assured that you’ve taken the right steps to protect your home.


Installing a window lock is much simpler than you may think. It only takes six easy steps – identifying the window style, choosing your lock, gathering your tools, removing any old locks, marking which spots to drill, and drilling it in. These steps are easy to follow, and I’ve provided a few examples of affordable tools you can easily find.

Even though it can look hard, it’s possible to take charge of the issues in your home and do the work yourself. I hope that these six steps help you feel more empowered to keep your home safe and save yourself money through DIY. Happy drilling!

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