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How To Tell If Someone Has Opened Your Door

Have you ever left your house or apartment wondering if someone had entered while you were away? It’s a common fear that can leave you feeling paranoid and anxious.

But fear not, dear reader! In this article, we’ll give you the short answer on how to tell if someone has opened your door, and dive into the various methods and tools you can use to ease your mind. So, let’s get started and put your worries to rest!

Some good ways to find out if someone has opened your door is to…

Leave a small piece of paper or dental floss somewhere between your door and the jamb when you leave the house and when you return and open your door, if those items are not where you placed them then you know that someone has been in your house.  

The idea is to use something small enough that won’t be detected if it falls out. Of course, another way is to install an outdoor and/or indoor security camera.

Living alone can be stressful, from paying your own bills and grocery shopping to cooking for one. For women – more so than men – the feeling of danger that someone could break into your house without warning adds an additional level of stress and insecurity.

We all want to live in a safe place, so here are a few things you can do to know right away if someone has entered your home.

How Can You Tell If Someone Was In Your Apartment?

For those of you who may be extra worried about a break-in but don’t have the funds for a costly home surveillance system or a slew of outdoor motion lights, there are some low-cost tips to help monitor your door.

The most important thing is for you to know if someone has entered and left while you were out before you enter the house.

In these cases, marking your door on the outside will help you to know if your door has been tampered with, even if the intruder shuts it again on their way out.

Putting a small item between your door and jamb (dental floss is great) is a great way to know if someone has been in your apartment. Installing an indoor security camera like the ones from Simplisafe is another great way to keep an eye on things.

If someone entered your house or apartment while you were away, they might be gone by the time you get back, absconding with your valuables or casing your home. Keep an eye out for the obvious and slightly less obvious signs to help protect yourself.

If you suspect that someone has been in your home – DO NOT ENTER – instead back away and call 911 immediately.

How To Mark A Door To See If It Has Been Opened

There are many inexpensive and easy ways to mark a door. As mentioned above, these methods generally involve placing something small and unobtrusive on the door or between the door and the jamb. 

You want to make sure to either place the object high enough, so it’s above eye level, or low enough so that it won’t attract notice if it falls.

Here are some items you can use:

  • Matchstick 
  • Pierce of cellophane tape
  • Strand of hair 
  • Dental Floss

The Matchstick Trick

One option is to place a matchstick in the door jamb (the crack on the side between the wall and door, where the hinges are) when the door is closed.

When the door opens, the gap will widen, and the matchstick will fall on the floor. Make sure to place it low enough so that if it falls, it will not attract attention. 

Note: Ensure you place the matchstick on the side of the door that swings away from you. If you have an outward-opening door (one that swings toward you), this trick may not work. You can take a look at this handy door diagram for more detail.

Tape On Door Trick

Another option is to place a piece of clear cellophane (plastic) tape at the top of your door. Make sure it overlaps the door and the frame. If the door opens, the tape will either break or pull off and fold when the door is shut again.

Either gift wrap tape or packing tape would be best for this as they are more transparent than regular Scotch Magic tape. Make sure you use a small enough piece that it won’t make a sound when ripped off. 

Test a few different lengths of tape and placement on the door before putting this into action; this ensures you have the stealthiest location.

The Hair Trick

If you don’t have tape on hand, you can do the same thing with several strands of hair. If you dampen them first, they should stick to the door frame with the help of static.

Again, make sure your place your hair horizontally across the door and frame. If you come back and the strands of hair are not there, you’ll know that someone’s gone through the door.

Dental Floss

The Hair Trick method can also be used with dental floss.

Note: This may not work well on an outside door that is exposed to the elements. Wind or precipitation can dislodge the hair or dental floss.

Other Ways To Check If Someone Has Opened Your Door

Check The Door Frame

Checking the door frame for signs of tampering is an important step in determining whether someone has opened your door. Here are some detailed steps on how to check the door frame:

  1. Inspect the door frame: Start by examining the door frame itself for any visible signs of damage or tampering. Look for scratches, pry marks, or any other indications that someone may have tried to force their way into your home.
  2. Check the hinges: Next, check the hinges on the door frame for any signs of damage. Look for bent or broken hinges or screws that have been pulled out of the frame.
  3. Check the strike plate: The strike plate is the metal plate on the door frame that the latch or deadbolt locks into. Examine it for any signs of damage, such as bent or missing screws, or scratches or pry marks.
  4. Test the door: Finally, test the door itself by opening and closing it several times to see if it functions normally. If there are any signs of resistance or the door does not close properly, it could be a sign of tampering.

If you do find any signs of tampering, it’s important to contact the authorities immediately and avoid entering your home until the police arrive. Do not touch anything or attempt to clean up any evidence, as it may be useful in the investigation.

Test The Latch And Locks

Inspecting the door’s latch and locks is an important step in determining if someone has opened your door or if there are signs of forced entry. Here are some steps on how to inspect the door’s latch and locks:

  1. Check for physical damage: Look for any physical damage to the latch or lock, such as scratches, dents, or chips, that may indicate tampering.
  2. Test the latch and lock: Test the latch and lock to ensure they function normally. If the lock or latch appears to be loose or not secure, it could indicate tampering or forced entry.
  3. Check for key marks: Examine the lock and latch for any marks that may indicate someone has used a key to gain entry.
  4. Use a flashlight: Shine a flashlight into the lock to check for any foreign objects, such as pieces of paper or other materials, that may have been inserted to manipulate the lock.
  5. Check for picking marks: Look for any picking marks on the lock itself or on the surrounding area that may indicate someone attempted to pick the lock.
  6. Check the strike plate: The strike plate is the metal plate on the door frame that the latch or deadbolt locks into. Check the strike plate for any damage or signs of tampering.

Again, if you do find any signs of tampering or forced entry, it’s important to contact the authorities immediately and avoid entering your home until the police arrive.

Motion Detectors and Cameras

If you have some extra money, you may want to invest in a low-cost motion detector alarm, such as SimpliSafe, or security camera. Do be aware that, however, some of these devices require an existing smart home setup, so make sure to do your research before buying.

Amazon’s Alexa Guard

There are some amazing things (called skills) that Amazon’s Alexa device can do and one of these skills is called Alexa Guard which is free but now has a Plus package that costs $5.00/month or $49.00/year.

Basically, when you activate Alexa Guard it will “listen” for noises such as smoke alarm, carbon monoxide alarm, breaking glass, etc. Then it will do a recording and send you an alert (to your smart phone) with the recording so you can hear what’s happening.

In addition – when it hears the noise it can also turn your smart lights on which may deter someone if they are breaking in.

The pro version of Alexa guard can do much more.

Customers who pay for a subscription will be able to ask Alexa to call Emergency Helpline for them to request medical, fire or police assistance. The service also gives Alexa the capability to detect sounds of activity in the house if its residents are away and to sound a siren from Echo devices if it does. Alexa could also play the sounds of dogs barking from the speakers if connected outdoor security cameras detect motion outside the door.

Engadget.com

Here’s a great video talking in depth about Alexa Guard.

5 Indicators That Someone Has Broken Into Your Home Or Apartment

Your Belongings Are In Disarray

You may immediately notice that the items in your home have been moved and / or scattered about.

Thieves usually enter an empty home to search for valuables like cash, electronics, or jewelry. Because of this, they will often dig through drawers and open doors.

Also, check if furniture or other items have been moved or upset. 

Your Valuables Are Missing

Check your bedroom, closet, and office (or wherever you keep your high-value items). If you are missing pieces of jewelry or your PlayStation, you’ll want to report it to the police right away. 

Your Locks/Windows Have Been Tampered With

Check your locks. If someone used lockpicks (which are readily available to buy) or other tools to force your locks open, there should be visible damage. This may come in the form of small scratches to obviously broken hardware. Also, check the hinges of your door for damage.

Then, check the windows around your house—especially the first floor or windows that are easily accessed. They may be obviously broken, or the latch/frame may have been forced open.

Ensure that all your windows closed and locked. If they aren’t, it’s a good chance that someone’s broken in.

You Find Unfamiliar Footprints Or Marks On Surfaces

Check the carpet/floor for muddy boot prints or new scuff marks on tile or hardwood. You may also want to look for new or unfamiliar footprints in the snow or garden beds surrounding your house. 

You may also see unfamiliar fingerprints or smudges on walls or countertops or notice details like hair (that’s obviously not yours) or dirt that has been tracked around. 

Check Your Surveillance Footage

If you have a home surveillance system or a doorbell camera such as a Ring, you may want to check that as well. It may seem obvious that no one would mess with a house with a security camera, but you would be surprised.

What To Do If You Think Someone Broke Into Your House Or Apartment

If you think someone broke into your house and has now left, follow these steps to ensure you are protected. 

Get To A Safe Place

First and foremost, you want to ensure your own safety. Do not enter the property. Go to a neighbor, a friend, family, etc. Don’t put yourself needlessly at risk to investigate. That is a job for the authorities.

Call The Police or 911

Once you arrive at your safe location, call the police. Ensure you give them all relevant information such as your name, address, and anything you may know about the intruder.

Document The Situation

Take photos or video of any damage or signs of forced entry. This can be helpful for insurance claims or police investigations.

Work With Police To Take Inventory

The authorities need to clear the crime scene first, but after that, it is your job to determine if anything’s been taken. Include a thorough description of anything that’s been taken. You also want to work with the police and answer all their questions as thoroughly as possible.


Note: A good idea is to always have a written and digital inventory of your items. You can use Log Books like these and in addition – take digital photos of your items.

Contact Your Landlord Or Property Manager

If you rent your home or apartment, contact your landlord or property manager to let them know what happened.

Call The Insurance Company

If you can, call your insurance within 24 hours and file a claim. They will help you recoup some, or all, of your losses. Makes sure you’ve also sent all the information to the police first as the insurance will need to know this.

Repair The Damage

While this situation may be emotionally taxing, it’s also essential to act practically. Clean up everything that’s been damaged. Adding extra layers of protection will also help reduce the feelings of vulnerability that follow a traumatic incident like this.

Take Steps To Secure Your Property

Once the police have cleared the property and deemed it safe, take steps to secure it. This may involve changing locks, installing a security system, or repairing any damage.

What Do You Do If You Think Someone Is In Your House?

If you come home and find your door marking is damaged, and you suspect someone is still in your house:

Stay Calm

Don’t make unnecessary noises to let the intruder know of your presence. If someone is in your home, you cannot be sure of their intentions and if those intentions include harm to you. 

Don’t Confront The Intruder

Confronting them gives them a choice to either flee or fight, and unfortunately, you won’t be able to know whether they’ll attack you or if they’re armed. 

It is best to remove yourself from the situation altogether. Escape from a nearby exit if possible and go to a neighbor or nearby family or friend’s home where it’s safe.

If you don’t think you can get out safely, lock or barricade yourself in a nearby room. Find a good hiding place within that room to take shelter and remain quiet. 

It’s also wise to find an object in the room you can use to protect yourself if the need arises before you have a chance to call 911. 

One trick that you can do, especially if you live alone is to make sure that there are items throughout the house at all times that you can use as a weapon. Some ideas are…

  • Simplisafe panic buttons throughout the house
  • Heavy coffee mugs can inflict some pain
  • Fire extinguishers
  • A hammer or a heavy wrench
  • A baseball bat
  • Pens and knives can be used to stab someone
  • Scissors
  • Bug spray or pepper spray
  • Flashlights

Put items like these everywhere, under the bed, in the closets, etc.

Call The Police Or 911

Let the authorities know of an on-going break-in and let them handle the rest. Once they deem your home is safe, then take stock of your belongings and report any missing items. Call the insurance company if needed, then work on repairing any damage present.

Final Thoughts

In conclusion, if you follow the tips listed above, you will get an early warning on whether your home has been broken into.

Remember that the most important thing is to keep yourself safe, so if you ever feel like you’re in imminent danger:

  • Leave the area, if possible, and ensure you’re somewhere safe.
  • Call 911.

Items can be replaced, but your life cannot.

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