The difference is that you need to lock the door from both inside and outside with the key.
Single vs double cylinder door locks.
This is useful for doors with glass panels or near windows.
The number of cylinders inside a lock translates to the number of keyed entries on the door.
Double cylinder locks is the number of cylinders.
A single cylinder has a keyed entry on one side while a double cylinder has keyed entries on both sides.
The single cylinder deadbolt is the most common.
The primary difference between single cylinder vs.
Double cylinder locks contain two cylinders.
Single cylinder use a keyed on the outside and a thumb turn on the inside.
It is found on front or back exterior doors and requires a key to open it from outside.
A thumb turn opens it from the inside.
Single cylinder locks are usually less costly to purchase and install than double cylinders.
It means that you will need to use the key to unlock the door no matter which side you are on.
The two main reasons for this are efficiency and economy.
This difference has one primary trade off.
Double cylinder deadbolts are locks that require a key to open from both the inside and outside.
Doors outfitted with single cylinders are unlocked with a key from the outside but do not require a key for unlocking from the interior of the property.
A simple thumb turn locks and unlocks the door.
This means that a key will be required to turn the lock both on the inside of the door and the outside.
No one can break the glass and operate the thumb turn to enter.
Single cylinder locks have only one lock cylinder as the name implies.
Double cylinder door locks.
Just like single door locks you will also require to use the key to lock the door.
Double cylinder locks use a key on both sides.
This prevents intruders from entering and exiting easily.
While the single cylinder deadbolt only features a locking mechanism requiring a key on one side the double cylinder deadbolt has it on both.
Single and double cylinder door locks provide options for exterior doors.
On the other hand single sided deadbolts require key to unlock from the outside only.
Instead the door is unlocked with a thumbturn style lever.
Single sided deadbolts have a knob on the inside that is used to unlock and lock them from the inside.
Single cylinder locks are more common than double cylinder.
Single cylinder deadbolts are the commonest type in most homes.