How To: Lock a deadbolt from the outside with no keys

Do you need to lock the door but don't have the keys? This may happen if you are sharing your keys with someone else, staying at a friend's house, or for a variety of other reasons. Check out this video for a sneaky way to secure that door tight without even sticking a key in the lock.
You Will Need:

* String
* Tape
* A pen or pencil

Step 1: Lock the door
Lock the deadbolt while you're still inside.

Step 2: Secure pencil
Secure the pencil or pen to the top of the deadbolt's lever using string or tape. Make sure it is securely fastened to the lever, and then unlock the deadbolt.

Step 3: Cut string
Cut a piece of string long enough to reach from the deadbolt lever inside of the closed door and over the top of the door while leaving enough slack on the outside of the door to pull the string.
You can use packing tape instead of string by securing one end of a long piece to the deadbolt lever, and then wrapping it around the side of the door so you can pull it from the outside.

Step 4: Fasten the string
Fasten the string to the end of the pencil that needs to get pulled in order to lock the deadbolt.
Make sure you have all of your belongings before you leave. Once the door is locked, you won't be able to get back inside.

Step 5: Exit
Exit, bringing the string outside with you before you close the door. Once the door is closed, pull the string to engage the deadbolt. Listen for the click and then check the door to make sure it locked. Cut the hanging string if you like.

Did you know? The earliest known tumbler locks were made of wood and used in Egypt about 4,000 years ago.