The Difference Between Single-Cylinder & Double-Cylinder Deadbolts
Deadbolts are essential for home security—but not all deadbolts work the same.
The biggest distinction is between single-cylinder and double-cylinder deadbolts.
Here’s what sets them apart and which option is right for your home.
1. What Is a Single-Cylinder Deadbolt?
A single-cylinder deadbolt:
✔ Uses a key on the outside
✔ Uses a thumb turn on the inside
✔ Is the most common option in U.S. homes
Best For:
✔ Front doors
✔ Garage doors
✔ Most residential exterior doors
2. What Is a Double-Cylinder Deadbolt?
A double-cylinder deadbolt:
✔ Requires a key on both sides
✔ Has no thumb turn inside
✔ Provides higher security in certain situations
3. When to Use Each Type
Use Single-Cylinder If:
✔ You need quick exit in emergencies
✔ You live in a standard suburban home
✔ Your door has no large glass panels
Use Double-Cylinder If:
✔ Your door has glass windows
✔ You want to prevent break-ins via broken glass
✔ Security priority > convenience
4. Safety Note About Double-Cylinder Locks
In some states, double-cylinder locks are restricted due to emergency exit concerns.
Always check local building codes.
