Is a Dual Cylinder Deadbolt Against the Law?

Dual cylinder deadbolts require a key to open the deadbolt from both the inside and outside. The locks have no handle. These locks can create an issue for quick exit if a fire or other hazardous situation occurs.

In the U.S., there is no single comprehensive law against dual-cylinder deadbolts. Individual cities and states have local property and fire codes that may prohibit the use of dual-cylinder deadbolts. The code may prohibit the use of dual-cylinder deadbolts in some buildings and allow them in others.

The city of San Jose in California prohibits the use of dual-cylinder deadbolt locks in homes. According to San Jose's Uniform Building Code, "deadbolts must be openable from the inside without a key or any special knowledge. Deadbolts with a latch on the inside are the ones approved for residential use."

The state of Texas allows for the use of dual-cylinder deadbolt locks in homes. According to the Texas property code, "They are not illegal, but it would be prudent for you to consider the possible liability of a tenant or children trapped inside your dwelling during a fire."

Clearly identify the location of the keys to a dual-cylinder deadbolt lock to all occupants. In an emergency, an occupant may forget where the key for the deadbolt lock is. The chances of this happening to children are much higher than for adults.