Door locks come in many shapes and forms, and deadbolt locks are particularly useful for exterior entrance security. This guide reviews the different types of deadbolts available, and details why they provide better defense against intruders than basic door locks.

Types of Deadbolt Locks

Single cylinder

With a keyhole on the outside and a knob or lever on the inside that can be used to unlock the door, single cylinder deadbolts are standard in most homes. However, since no key is required to flip the inner lever, use these locks on doors without windows. Also, avoid installing these locks on doors with windows within arm’s reach of the doorknob since the lock could be circumvented by reaching through the window.

Double cylinder

This lock type requires a key for both entries and exits, adding an extra layer of security, so, rather than a lever on the inside, there is a second keyhole. Needing to locate a key before opening the door from within can slow down exits, especially in low visibility situations such as house fires. While helpful for preventing break-ins, they are banned in some areas due to fire safety regulations.

Surface Mounted Deadbolts

Surface mounted locks provide extra security by placing the deadbolt mechanism on the interior side of the door, not passing through the door into the frame. Since the bolt is protected by the door, it’s more difficult for intruders to use saws, pry bars, or other tools against it. Since door frames are likely to give way under force, these locks attach to the inner wall rather than the door frame, giving the door extra strength.

Why Deadbolts are Important

door locksDeadbolts significantly increase resistance to forced entries since, unlike typical door locks, they don’t rely on a spring mechanism. Leverage can’t force them back into the door and typical lock picking methods, like slipping a credit card into the door gap, won’t work. Since deadbolts are a solid bar of metal, it must be cut or broken to be moved, requiring a higher level of time and effort than forcing a standard door lock. Among deadbolts, ANSI grade 3 locks have the most relaxed standards, while grade 1 locks have stringent requirements and are the most secure. ANSI grade 2 locks are recommended for primary entrances for homes and apartments. You can pair them with ANSI grade 1 locks on secondary doors, and grade 3 locks are rated for commercial security and business use.


If you want help installing new locks on your doors, contact A-Tri-County Lock in Cuyahoga Falls. With an A+ rating from the BBB®, they’ve served the Akron, Canton, and Cleveland area for over 30 years, making sure entrances are secure. They’re also registered members of the Association of Locksmiths of America. Call them in Akron at 330-928-6222, in Canton at 330-494-1188, on the East Side of Cleveland at 216-481-2233, or the West Side at 440-552-1410, to talk to a locksmith today, or visit their website for information on their services.