Deadbolt Locks: Which Type Do I Need?

When purchasing new door hardware for your home, some of the items you will most certainly need to purchase are deadbolt locks. Fortunately, deadbolt locks now are available in all popular finishes including oil rubbed bronze and satin nickel, as well as more traditional finishes such as polished brass and antique brass. You will also be able to find deadbolt locks in more obscure finishes, such as matte black and polished chrome. Therefore, finding deadbolts in the same finish as your new door hardware will be an easy task.

What is a more difficult task is determining the type of deadbolt that you will need.

There are generally only two main types of deadbolt locks: A single-cylinder deadbolt, and a double-cylinder deadbolt.

Single-Cylinder Deadbolt (Oil-Rubbed Bronze)A single-cylinder deadbolt uses a key mechanism on the outside of the door, and a latch on the inside of the door. A single-cylinder deadbolt will be an obvious choice on any exterior door that does not have glass in it or around it.

Double-Cylinder Deadbolt (Oil-Rubbed Bronze)A double-cylinder deadbolt, by contrast, uses a key mechanism on both sides of the lock – therefore, you will need to use a key on the inside of the door as well as the outside of the door. A double-cylinder deadbolt is traditionally used in cases where the door has glass in it or around it. Why? The theory is that a potential intruder could break the glass and simply unlock a single-cylinder deadbolt, whereas that would be impossible to do with a double-cylinder deadbolt because they would need the key to unlock it.

Seems simple, right? Not so fast.

Many local building codes have forbidden the use of double-cylinder deadbolt locks in new residential construction, and in my opinion, for very good reason.

Double-cylinder deadbolt locks can be dangerous because you could possibly lock yourself or other family members in the house during an emergency. For example, let’s assume that you have a double-cylinder deadbolt lock on your front door because your front door has glass in it. Your stairwell comes right down to the front door, but you leave your keys on a hook in the kitchen in the back of the house. A fire starts in your kitchen (where your keys are) and spreads heavily enough that the kitchen is inaccessible. Your smoke alarm sounds in time for you (and your children) to awaken and get out of the house, but the only safe first floor exit is your front door…..and you are now locked in.

Though this is a fairly dramatic scenario, it is a plausible one. It’s also not the only scenario in which you would not want to be locked in your own house.

So your solution is to always keep the key in the lock, right? That doesn’t make any sense, since that contadicts the reason you installed a double-cylinder deadbolt lock in the first place!

So what do you do? In my opinion, you play the odds. I have two children, and for that reason alone, I would never use a double-cylinder deadbolt lock on my house. The probability that we will be broken into during the middle of the night is less likely than the possibility that we might have to make an quick exit out of that door. Furthermore, the “bad guys” aren’t as sophisticated as we give them credit for, and they don’t normally operate like they do in the movies. The majority of break-ins that I have seen are done by either kicking the door in or by using a pry-bar to force the door open – in either case, a double-cylinder deadbolt lock would offer no more protection that a single-cylinder deadbolt lock.

If you are considering using a double-cylinder deadbolt lock, I can only offer the following advice:

  • Never leave a key in the lock. If you plan to do that, you might as well just get a single-cylinder deadbolt lock.
  • Keep the key near enough to the lock that you can easily retrieve it, and make sure everyone in the house knows where it is. Also make sure that it is within reach of everyone in the house, including children.
  • Make sure that everyone in the house understands how to use the key in the lock – this is especially pertinent if you have younger children.
  • Keep a second key to the door where you sleep, such as in a nightstand in the bedroom.

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