Why Burglars Love Sliding Glass Doors & How to Burglar-Proof Yours

February 09, 2016

That large, sliding glass patio door that you love because it lets in so much natural light? Yeah, burglars love them, too.

What is a beautiful home feature to you is a welcome sign for many burglars. Why? Well, according to one former burglar it’s because sliding glass doors: 

  • Are often unlocked. In his experience, people often forget to lock the back sliding glass doors.
  • Have locks that are easy to “pick”. Even if they are locked, many can be unlocked simply by jiggling the handle. (Here’s a video demonstration.)
  • Advertise what’s in your home. Those large windows make it easy to see all the great stuff you have that burglars want.
  • Are in your backyard. In the back yard, there’s less chance of being seen by neighbors or passersby. 
  • Are made of glass. If all else fails, glass breaks pretty easily. And since sliding glass doors are tempered glass for safety, burglars don’t have to worry about getting cut.

So what’s one to do? Board up the sliding glass door permanently? Replace it with large, locking steel doors? Both are options, though not great ones. 

Below, we’ll show you the 3 ways burglars break in through your sliding glass door and how you can prevent or deter each one.

1. Bypassing the “lock”

Most sliding glass doors come with a lock that is really just a latch. It shouldn’t be relied on to keep burglars out of your home. Here’s a video demonstration of a homeowner unlocking his simply by jiggling it a bit.

What you can do

Install a better sliding glass door lock. You have a lot of options, but here are the best ones we recommend:

Security bars
Security bars are strong metal bars that attach to one side of the door frame and then are extended or folded into place and brace against the sliding door to lock it into place.

Security bar keeps out burglars
Master Lock 265DCCSEN Dual-Function Security Bar shown bracing a sliding glass door

You can create something similar yourself. Cut a dowel or piece of 1x1 wood to the width of your tracks when closed. Then place the brace in the tracks to “lock” the door. 

Traditional sliding door locks
The most common type of sliding door lock is a basically a bolt that attaches to the sliding door. When shut, the bolt slides up into the frame of the door to secure it. A key then locks the bolt in position.

Traditional door sliding lock
How sliding door locks work. Image via Amazon.

Double bolt locks
This is a newer type of sliding door lock. Double bolt locks are 2 pieces. One piece attaches to the frame of your door. The other attaches to the sliding door. When shut, the piece that attaches to the frame nests inside of the piece that attaches to the door. Metal bolts then slide into the piece attached to your frame to secure the door.

Check out this video to see how they work.

Door sensors
While not a substitute for a good lock, door sensors help keep your family and belongings safe. When the door is opened, they will trigger your alarm. And a sounding alarm can be enough to scare off some burglars because they don’t want attention called to what they’re doing.

Contact sensor
A Honeywell wireless door/window contact sensor

2. Lifting the door out of its frame

Another way burglars break in through your sliding door is by physically lifting the door. Using a crowbar, burglars can actually lift up the door, move it off the tracks and out of the way.

How’s this possible? Well, this is how the door was put into the frame when it was made. The burglars are just reversing the process. 

What you can do

Install a better sliding glass door lock. (Sound familiar?) With the exception of the security bars, all the options listed in the first section also work well to prevent thieves from just lifting the door out of its frame.

3. Breaking the glass

Even with the best door lock and working door sensors a thief can still break in through your patio door simply by breaking the glass. “Won’t that make a lot of noise?” you might be thinking.

Sure, but if you’re not home they’ll still get a bunch of stuff before anyone gets there. Plus, if they see something they really want and think they can get in and out quickly, they may simply smash the glass, grab it, and go—even if you’re home.

What you can do

Glass is always going to be a weak point in your home’s security system. But here are some ways to strengthen it:

Replace your door with an impact-resistant sliding door
Many door and window companies make impact-resistant or “hurricane-proof” sliding doors that cannot be easily broken. However, they are expensive, heavy and difficult to install.

Window film
Security window film is a thin, protective sheet that can be applied to glass to make it more difficult to break through. It won’t make your sliding doors impenetrable. But it can make your home a more difficult target and give more time for authorities to get there, especially when paired with a glass-break sensor (below).

Check out this video demonstration.

Glass-break detectors
Glass-break detectors will sound your security system’s alarm when glass is broken in your home. Just like with door sensors, a sounding alarm can be enough to scare off some burglars.

In fact, in an interview, one former burglar said the mere presence of them was enough to make him go to the next home.

“When they see that glass break [sensor] attached to that window, they know that this is a well-secured home. Stay away from it."

We suggest installing dual-tech glass-break detectors. A traditional acoustic glass-break detector senses the frequency of glass breaking and sounds your security system’s alarm. 

However, that can lead to false alarms if, let’s say, a glass vase drops. Dual-tech glass-break detectors combine acoustic glass-break technology with shock glass-break technology.

That means the detectors must sense both the frequency of glass breaking and the shock against your window before setting an alarm off, reducing false alarms. 

Glassbreak detector
A Honeywell dual-tech glassbreak detector

Did you find this article helpful? Read our other articles on home security tips and tactics

Ackerman Security is dedicated to protecting you, your family, your home and your belongings. If you have any security-related questions ask one of our experts in the Atlanta, Philadelphia or DC-area.