Greg B. wrote in asking about the benefit of window sensors for a monitored security system that he is planning for his new home in Carmel Valley. In my opinion, the benefit is little or none.
In a modern home with modern double pane windows, it is virtually impossible to open those closed and locked windows from the outside. A window sensor can ONLY detect a window going from closed to open, so if you can not open it from the outside there is not anything to detect. Most window break-ins occur through open windows. If your window is open even an inch, you would have to bypass that sensor before you could arm your system, so entry through an open window would not set off the alarm. The other way that a burglar would enter through a window, which is much more rare, is to break or cut the glass. If the burglar then enters through the hole that is created, the window frame is not moved and the window sensor and magnet are not separated, so the alarm is not tripped.
So long as you have at least one motion detector as part of your security alarm system, an intruder entering through a window will trip the alarm when they pass through the area covered by the motion detector. Modern motion detectors are “pet immune”, so even people with animals roaming in their home can effectively use motion detection to secure their property. Electronic security systems are designed to instantly go into alarm if the motion detector picks up human movement in the home and an entry door was not open first, so their is no delay in the siren sounding and scaring the intruder out of the property.
The only practical use for window sensors are for windows that you like to leave open a few inches to allow fresh air to enter your home. In that instance, you can get a “vented window” sensor where two magnets are installed. One magnet lines up with the sensor when the window is closed, and the second magnet lines up with the window open a few inches. Now you can arm your system with the window open to the vented position, and if any of those open windows are opened further by a would be intruder, the system instantly goes into alarm. This can be done on just two or three windows in the house, which is very affordable. To put sensors on all of your windows is very costly, and can make for a cumbersome system that is difficult to use. Typically when a system is difficult to use, people do not get in the habit of arming their system and all of that money they spent on window sensors is a complete waste!
Keep it simple and create the habit of arming your system, and your home will be secure.
Wow. No benefit to window sensors!? Ever here of a crowbar? And even if they don’t break open a window…having window sensors lets you make sure your windows are shut before you leave home. I would say there a pretty valuable part of the system. As far as expensive…most wired window sensors cost about $2-$5…wireless are a little more pricey…but still that’s pretty cheap in my opinion.
I don’t know what your opinion is based on. Many people form opinions on subjects that they have little or no factual information to base them on. My opinion is based on real crime statistics and personal experience of securing homes AFTER they are broken in to and learning how the intruder gained entry in to their home. Ultimately it is my job to give my customers peace of mind. If putting sensors on all of their windows achieves that, then I am more than happy to do that for them. You are correct that if a home is wired (most are not), the cost is not substantial, however wireless sensors add about $75 each to the cost of a system. With 20 windows that is $1,500, which I don’t think is “cheap”. Thanks for your comments. I am glad to see that people are checking out the site. Best wishes, Keith
it would make sense that a thief would look for an open window downstairs and no cars on the drive, when you can grantee they have gone out, there is a good chance that they don’t have a burglar alarm as if they did then the window sensor would prevent them from setting it. Then s/he could just climb in the window, if the alarm does start going off then they would know that no one is home and would have about 5 / 10 mins of robbing before a neighbour gets annoyed at the sound and looks out the window. most people wouldn’t bother to call the cops either. this is simple logic even a dumbass thief could figure it out.
First of all, if a window is open as you describe in your comment, then a window sensor would prove useless, since that zone would have to be bypassed in order to arm the system. Second, statistically the most likely intruder is a teenager looking for drug money. He or she is a bad kid since they are stealing from their neighbors, but they are still a kid, and very scared to be in a stranger’s home. I doubt that they will linger for 5-10 minutes with a 100+ dB siren blaring. They will likely leave the premises as quickly as possible and run away, which is exactly what we are hoping to accomplish. Your assumption that a “dumbass thief” can figure anything out is being very generous to the dumbass. Actual crime statistics don’t support your assumption. Thanks for your comments.