Choosing the Most Secure Storage Lock

Self Storage Tips How to Choose a LockBefore moving your family's belongings into your storage unit, you need to purchase a lock to secure the door shut to your unit. Pay careful attention to the type of lock you purchase to make sure that your valuables will be protected against possible break-ins, theft or vandalism. There are many different locks to choose from. Each lock will fall under one of two categories: either a padlock or a combination lock. Before choosing the lock that will work best for you, you will want to ask yourself a few questions... 1. How valuable is the property in storage? Chances are that since you have made the decision to rent a self storage unit to keep your belongings, they have value. Whether the property is a vintage sport car valued at $100,000 or your kids' baby photos that are purely sentimental, you will want to keep your items protected. Be sure to shop for a durable, tamper resistant lock. 2. Will the lock be used indoors or outdoors? Is your self storage unit located inside an indoor facility? Or is your unit accessed from outdoors? In this case, the lock will be exposed to the outdoors and subjected to environmental elements such as rain, freezing cold temperatures and extreme heat. These environmental elements can corrode the lock and extreme temperatures can cause the metal to expand and contract. A lock made from stainless steel or brass will resist corrosion from environmental elements. However, locks made from brass offer the best protection against corrosion. When compared to alloyed steel or stainless steel, a brass lock is more resistant to being cut with metal cutters or levered open by an intruder. 3. What will the lock be attached to? Before attaching your lock, you will want to inspect the clasp on the door to your unit that the lock will be secured to. Be sure that the clasp is tightly fixed in place and free from defects and gaps, where the lock could slip off the clasp, making the door vulnerable to intrusion. Any defect in the clasp will need to be reported to the facility operators for repair. When you have determined that the clasp is in good condition, you will want to attach your chosen lock. It is always best to choose a lock that is durable and tamper resistant. 4. How vulnerable is your property? Consider where your self storage unit is located. Is it located in an area where there is a lot of foot traffic or high crime? Both of these factors increase the chance that an intruder might want to tamper with the lock to break into your unit. A durable lock can deter thieves from breaking into your unit. The lock you choose to secure your storage unit shut will either be a combination lock or a padlock. You will need to be familiar with each type of lock to determine which type of lock is best for you.

Combination Locks

A combination lock is a lock in which a set of numbers are turned and lined up to unlock the lock. There are single dial locks and multiple dial locks to choose from. A multiple dial lock will require the use of several combinations to open the lock. Single dial locks can offer greater protection than a multiple dial lock.

Single Dial Combination Locks

A single dial combination lock operates using a single sequence of numbers that must be lined up on a single rotating dial. Single combination lock is typically opened by turning the dial in correct sequence, clockwise to the first number, then back counterclockwise to the second number and then again clockwise to the third number and so on alternating back and forth until the last number has been reached. The mechanism inside the dial is made up of discs or cams that line up when the correct sequence is reached. When the correct sequence is reached, a click is heard indicating that the tooth in the inner mechanism has settled in the notch. When his happens, a tug on the lock will open it. It is important that when choosing a single dial combination lock that some models have a 40 position dial that gives away the last number in the combination. This happens when the first two numbers in the combination have a mathematical relationship with the last number. The resulting mechanical weakness reduces the possible combinations to 100, a good combination lock should have about 64,000 possible combinations to deter break-ins by an intruder.

Multiple Dial Combination Locks

These locks operate using several rotating discs with notches cut into them. The multiple combination lock is secured with a pin that has several teeth that has teeth that hook into rotating discs. When the person operating the lock aligns the notches of the lock align with the teeth on the pin the lock can then be opened. The multiple combination lock is considered to be much less secure than a single combination lock. These locks are recommended for bicycles and luggage. They are not recommended to be used to secure the door on a self storage unit. These locks can be broken into without the known combination by aligning the machining part's slight irregularities. The pin can be pulled outwards and one of the teeth will pull more strongly than the other teeth on the corresponding disk. An intruder can rotate the disc until a slight click is heard, when the tooth settles into the notch. The intruder then repeats the procedure on the remaining discs until the lock is opened.


Padlocks require a key to lock and unlock. Usually a pad lock will come with two keys. It is a good idea to carry one key on your key ring, and keep the other in a safe place in case the first key is lost. Although a key is used to open the padlock, the inner operating mechanism for a padlock is similar to a combination lock. When choosing a padlock it is important to know that an inexpensive lock will generally be made from poor quality materials and a shell casing made from soft metal. Poorly made locks can easily be pried open or cut with bolt cutters. A good quality lock will have a hardened steel shackle, that has a double lock at both the toe and heel of the padlock. A good lock will have a 5-pin tumbler and a thick shackle. The shell casing of the lock will also be made of a hard brass metal or stainless steel. A good padlock will require very little maintenance. However, the inner working mechanisms in padlocks can become stiff over time. Use an air compressor to blow dust out of the inside of the padlock. If this is done on an annual basis, it should keep the lock working like new for many years. Padlocks can be divided into three categories.

Handy Locks

Handy locks are less expensive locks made from lower grade soft metal alloy materials. Some of these locks may have only a single lever or ball catch. These locks are not recommended for self storage units as they can easily be broken into with simple tools or an unbent paper clip. Many combination locks are also considered handy locks. These types of locks are more suitable for gym lockers and tool boxes.

General Purpose Locks

General purpose locks offer more resistance to break ins than a handy lock. General purpose locks are made from brass or stainless steel. They are designed with multi levers and offer a reasonable level of security. General purpose locks that are made from stainless steel, have a hard shell casing and collar offer good protection from being cut open with bolt cutters.

High/Maximum Security Padlocks

These are made from hardened materials, such as brass and stainless steel. A maximum security lock will have numerous pins inside the locking mechanism. There are millions of different key possibilities for this type of lock providing greater security. A maximum security lock will have a 5-pin anti lock tumbler, a brass cylinder, a hardened shackle and a dual ball locking. Locks will usually range in price from $2 - $20. A durable lock that provides the most security will usually cost around $25. Some commercial grade padlocks sell for over $100. However, before investing in a higher priced commercial lock compare the security features with a maximum security lock for about $25. While it is a very worth while investment to pay the higher cost to know that your valuables will be better protected in your storage unit, a maximum security lock can be as good or better than a more expensive commercial lock. The advice on this website is provided as a courtesy for informational purposes only. “Storage Tips” are offered as-is and no warranty is expressed or implied. For more information, see StorageFront’s Terms and Conditions.