Double-Cylinder Deadbolts Vs. Single: Which One Is Better?
Double-cylinder deadbolts and single-cylinder deadbolts are both used on residential and commercial properties, but double-cylinder deadbolts are more often found at businesses than at homes. This is, in part, because double-cylinder deadbolts provide the extra security that business owners often desire.
If you want to know what further separates these two kinds of deadbolt, read through the sections below, where both double- and single-cylinder deadbolts are described in detail.
Double-cylinder deadbolts provide more security than single-cylinder deadbolts, but at the cost of convenience. The deadbolts have similar price ranges, but the double-cylinder tends to be more expensive since more components are used. Both deadbolts can go well with a variety of decors, but the double-cylinder doesn’t have a thumb-turn, making it more attractive.
What Is a Double-Cylinder Deadbolt?
Double-cylinder deadbolts utilize a lot of the same components that single-cylinder deadbolts use, but the main difference between these two deadbolts is that the double-cylinder requires two keys to unlock the lockset whereas the single-cylinder only requires one key.
Both keys must be turned in the same direction, and at the same time, for a double-cylinder deadbolt to unlock, making this a deadbolt that requires two individuals to operate.
Double-cylinder deadbolts are often considered to be safer than their single-cylinder counterparts, but many wonder if this added safety is worth the cost of convenience. Lastly, since a variety of hardware manufacturers make double-cylinder deadbolts, they come in a variety of styles and finishes.
The Pros and Cons of Double-Cylinder Deadbolts
There are a few significant benefits associated with using double-cylinder deadbolts, but there are some notable drawbacks as well. The good and bad qualities of these deadbolts will both be discussed in detail below.
Pro: Added Security
The main appeal of double-cylinder deadbolts is that they provide more security and safety than traditional single-cylinder deadbolts. They keep unwanted individuals outside, but they also keep loved ones safely secure inside.
Say, for example, you have a decorative front door that features a large glass panel. An intruder comes up to this and smashes the glass in an attempt to gain entry to the property. With a conventional single-cylinder deadbolt, all the intruder has to do is grab the thumb-turn and they’ll be able to get inside.
But with a double-cylinder deadbolt, there is no thumb-turn, so the intruder would have no way of disabling the lock after breaking the window. And since double-cylinder deadbolts often look noticeably different than single-cylinder ones, it’s quite likely a thief wouldn’t even attempt to break in after noticing the double-cylinder deadbolt.
Pro: Keeping Loved Ones Safely Inside
The other added element of security relates to how a double-cylinder deadbolt can help one secure their home from the inside. Say, for example, your house is home to young children or elderly parents who are suffering with dementia. You definitely don’t want either group going out of the house unsupervised, and it’s here where double-cylinder deadbolts really come in handy.
A child can easily turn the thumb-turn of a single-cylinder deadbolt, but such is not possible with a double-cylinder because two keys are required. Double-cylinders are also good if you have pets that aren’t supposed to go outside. When two individuals are there to unlock the double-cylinder deadbolt, it’ll be near-impossible for a pet to escape by them both.
Pro: Accommodate a Variety of Decors
Another attractive quality is that double-cylinder deadbolts can go well with a variety of decors. Therefore, if you’re someone who’s meticulous when it comes to items and fixtures contributing to a room’s overall decor, you need not shy away from purchasing double-cylinder deadbolts.
Whereas stainless steel is the most standard finish, one could also get brass, rose gold, and a variety of other finishes. And since double-cylinder deadbolts don’t have thumb-turns, you’ll be looking at the same kind of knob on either side of the door, and this may be attractive to somebody who really appreciates balance.
Since double-cylinder deadbolts include more components than single-cylinder deadbolts, they are more complicated and therefore more expensive. A double-cylinder deadbolt—especially one that has a unique finish and is made of durable materials—will run you about $100. A really good one could even be closer to $200.
Overall, the cost in dollars shouldn’t outweigh the level of safety a double-cylinder deadbolt ensures. One must compare the losses from a break-in with a device worth $100, and then it will be clear why purchasing a double-cylinder deadbolt is a good idea.
The biggest drawback associated with double-cylinder deadbolts relates to the main reason why these are purchased. Sure, the two-key system is great for security purposes, but it’s a huge hassle if you’re going in and out of the property consistently. It’s this undeniable reason which dissuades most homeowners from purchasing and installing double-cylinder deadbolts, despite the added security they provide.
A lock which provides more security at the cost of longer unlocking time is one thing, but a double-cylinder deadbolt is completely useless unless two people are there to unlock it. In reality, these are only suitable for places that are frequently used or inhabited by at least two people.
Con: Illegal In Some Places
In some places, double-cylinder deadbolts are banned, for they present an inherent safety risk. In the event of a fire, for example, rescue teams would not be able to access building occupants unless two people could operate the deadbolt on both sides of the door.
In most building fires, occupants are either disoriented or trapped, so it’s hard to imagine someone being able to access the interior locking mechanism in the event of a fire.
Also, you should know whether or not double-cylinder deadbolts are banned in your municipality before installing one. After all, you don’t want to find out the hard way!
What Is a Single-Cylinder Deadbolt?
Single-cylinder deadbolts are used in most homes and businesses. With a single-cylinder deadbolt, there’s a slot for the key on one side, and on the other side there’s a knob which features a thumb-turn.
A thumb-turn resembles a lever and moves in conjunction with an inserted key. In most cases, the turning mechanism is on the interior side of the door, as this is mainly where the lock will be engaged.
Single-cylinder deadbolts—unlike their double-cylinder counterparts—come in many shapes and sizes, and there are a range of thumb-turns available as well. In short, single-cylinder deadbolts are mainly bought because they provide security without sacrificing convenience.
Single-Cylinder Deadbolt Pros & Cons
Like double-cylinder deadbolts, single-cylinder deadbolts have attractive qualities and qualities that make them less desirable. Two important pros and cons are discussed below.
Pro: Security, Longevity, and Convenience All In One
Single-cylinder deadbolts have been standard for decades, if not centuries, because they combine security, longevity, and convenience. One isn’t going to break down the door easily if there’s a single cylinder deadbolt on it, and these can be used hundreds of thousands of times before they’re rendered inoperable due to wear and tear.
And of course, only one person is required to either lock or unlock a single cylinder deadbolt.
Con: Less Secure
Single-cylinder deadbolts are less secure than double-cylinder deadbolts in three particular ways.
- Single-cylinder deadbolts can be unlocked discretely using lock-breaking tools and techniques.
- Single-cylinder deadbolts can be easily disabled if they’re attached to glass doors and windows that are prone to smashing.
- There’s no inside security guaranteed by a single-cylinder deadbolt.
Double- and single-cylinder deadbolts are often compared, which explains why there are so many questions about both. Here, some of the frequently asked ones are answered.Where are double-cylinder deadbolts used best?
Double-cylinder deadbolts are used mainly at businesses which require tight security. Therefore, it’s not uncommon to see these at banks, government buildings, and high-end office towers. In short, they’re ideal in places where security is important and travel between rooms isn’t frequent.Can a bobby pin disable a double-cylinder deadbolt?
The technology employed in a double-cylinder deadbolt makes cracking it with a bobby pin impossible. The only thing that can unlock the double-cylinder deadbolt are the keys that come with it.
In the end, double-cylinder deadbolts and single-cylinder deadbolts are only really different in a couple of ways. These differences, however, are significant, and they’re often what lead homeowners and business owners to purchase and install one kind of deadbolt over the other.
Both deadbolts are great at providing extra security, but the double-cylinder is not nearly as convenient as the single-cylinder. Furthermore, they’re about the same in price, so appreciation of convenience is really what directs a purchasing decision.
Matt loves everything DIY. He has been learning and practicing different trades since he was a kid, and he's often the first one called when a friend or family member needs a helping hand at home. Matt loves to work with wood and stone, and landscaping is by far his most favorite pastime.
More by Matthew Mountain