Paul Cromwell, Ph.D., a professor of public affairs at the University of South Florida, in Tampa, interviewed burglars about their techniques for a book he cowrote called Breaking and Entering. Here, he reveals what can attract—and how to deter—thieves.

By Kaitlyn Pirie
Updated July 17, 2015
Peter Oumanski

Describe the typical burglar.
My research shows most are between the ages of 15 and 24 and live within a mile or two of their targets. Many scope out homes beforehand. To get intel, some even pair up with service people whose occupations can give them access to a house. The two may not work together on an ongoing basis, but they may share spoils of a job. Be aware of everyone who comes to your home—it doesn't hurt to be a little suspicious.

Are certain types of houses less likely to be broken into than others?
The homes that tend to be safer are the ones that are in culs-de-sac (the layout prevents an easy getaway) and those located on street corners (more visibility and passersby). And it's not necessarily true that prowlers will stay away from a property if it's obvious that a dog lives there. But a barking dog can help draw attention to a burglary.

Any other ways to decrease your home's chances of being a target?
Keep landscaping low around doors and windows so as not to provide cover for people trying to figure out how to get in.

How quickly does a break-in happen?
Burglars want to be in and out of a house within five to seven minutes. They run through the house and in less than a minute figure out where the good stuff is. Generally they go to the master bedroom first—that's where jewelry and cash are apt to be. Offices are also hot spots because of computer equipment.

In your book, you warn about repeat offenders.
If you've been burglarized once, there is reason to worry. There's about a 30 percent chance you'll fall victim again within a few months. According to the studies I've conducted, thieves assume you'll have new stuff by then, plus they already know how to get in. Figure out how they got in, and address the issue.

What about an alarm?
Yes, have one installed and flaunt it with a sign on the lawn or in a window.

What are some overlooked entry points?
Get rid of pet doors. A burglar could send a child through a dog door to unlock the main door. Also, keep the garage door closed, and lock the entrance between the garage and the house.

Talk to us about locks.
On all your doors, put dead bolts that go into the door frame 1½ inches. As for sliding doors, don't prop a broomstick in the track in the hope that it will prevent the door from sliding. Burglars can still lift the door off its track. You're better off installing a lock that goes through the doorframe. Your windows are fine with standard locks, but avoid burglar bars, as they can be a fire hazard.

How safe is a safe?
It can prevent petty theft—say, a repairman is in your home and you want to lock up pricey items. But regarding burglary, it's not that useful if the safe is light enough for someone to pick it up and walk off with your belongings inside. Buy a fireproof model, the heaviest possible, and consider bolting it to the floor. If you're going on vacation, the best thing to do is put valuables in a bank safe deposit box.

Tell us more about prepping the house before leaving on vacation.
Create an "illusion of occupancy." Enlist a neighbor to park his car in your driveway at night, bring the garbage can to and from the curb (make sure there's trash in there), and shovel the driveway if it snows. Also smart: Mow the lawn so it doesn't get overgrown, and have newspaper and mail delivery put on hold. Install outdoor motion-sensor lights, and put a couple of indoor lights on timers so the house is lit from dusk until 11 P.M. For insurance purposes, keep documentation of all your belongings.

Final thoughts?
Don't advertise on social media that you're on vacation. You're essentially telling the world that you're leaving the house unattended. Wait until after your trip to post about your getaway.