Double-cylinder deadbolts are much more secure than their single-cylinder counterparts, as their design eliminates the risk of intruders unlocking the door by breaking a nearby window and reaching inside.
However for fire safety reasons, they are not that common in the US, nor recommended. If you do have a double-cylinder deadbolt on an exterior glass door, and you want to add some smart features to it, then your options are limited.
There are only two smart locks available that can work with double-cylinder deadbolts.
My main recommendation is the Level Bolt Smart Lock. A wide range of double-cylinder deadbolt makes and models are officially supported (list below). It's also clear from feedback by testers and device owners that most have been able to get it working successfully.
If you try the Level Bolt and it doesn’t work for whatever reason, then it’s worth considering the SwitchBot Smart Lock. This is a lot less secure than the Level Bolt, as the key needs to be permanently positioned in the keyway.
Then the SwitchBot device automatically turns the key to lock and unlock the door. It’s more of a DIY hack than the Level Bolt which actually replaces the deadbolt.
What is a Double Cylinder Deadbolt Lock?
A double-cylinder deadbolt lock is a type of high-security door lock that requires a key to operate it from both sides. This design eliminates the risk of intruders unlocking the door by breaking a nearby window and reaching inside.
Generally made from sturdy materials, these locks are usually resistant to tampering, picking, and forceful entry, ensuring maximum home security.
Double-cylinder deadbolt locks are less common in the United States mainly due to safety concerns. As these locks require a key to unlock from both the inside and outside, they have the potential to trap occupants during emergencies like fires.
In a panic, finding a key becomes difficult and wastes crucial time, increasing the risk of harm.
These style locks are typically against fire safety regulations in the United States. Fire codes prioritize easy egress, so single-cylinder deadbolts, which feature a thumb-turn mechanism inside and a keyhole outside, are the recommended choice.
Are there any Double Cylinder Deadbolt Smart Locks?
There are two makes of smart locks in the US that work with double-cylinder deadbolt locks. Namely the Level Bolt Smart Lock and the SwitchBot Lock. I recommend checking their compatibility charts before purchasing, to ensure the exact make and model of your deadbolt is compatible.
- Lock Type: Deadbolt
- Material: Stainless Steel
- Finish: Satin Chrome
- Compatibility: Apple HomeKit, iOS, Android
- Battery: Included
- Door Profile: Fits 2-3/8" and 2-3/4" profiles
Say goodbye to searching for keys in the dark with the Level Bolt smart lock, which offers secure, hassle-free, and keyless entry to your home. Its geofencing technology detects when you're near the door with your smartphone, making unlocking quick and efficient. Additionally, this smart lock is strong and secure, featuring a reliable six-stage stainless steel gearbox.
It's officially compatible with a wide range of double-cylinder deadbolts such as the Baldwin Prestige Series, Defiant Standard Deadbolt, Kwikset 665 / 785 / 985 / 987 / Halifax / Milan Series. You can check out the official compatibility chart here.
The Level Bolt's design is both simple and elegant, as it discreetly turns your existing deadbolt into a digital lock without any noticeable hardware. Its minimalistic circular shape suits various door styles, while the satin chrome finish adds a sophisticated touch to your exterior doors
Installation of the Level Bolt smart lock is simple, requiring only a screwdriver to replace your current deadbolt. Designed to fit most standard exterior doors with American standard deadbolts, the lock ensures broad compatibility with both single and double-cylinder locks.
Thanks to its customizable backset, it adapts to various door profiles, making integrating advanced technology into your home easy and straightforward.
Unfortunately, the smart lock's connection and reliability can sometimes be inconsistent, requiring a Bluetooth repeater or dedicated hub to improve functionality. Despite this minor drawback, the lock's user-friendly nature and attractive design remain appealing.
- Stealthy, hidden design
- Easy installation process
- Compatible with HomeKit, iOS, Android
- Maintains existing lock's aesthetics
- Useful remote access features
- Battery life reported as "healthy" and lasting six months
- Can work with double-keyed cylinders
- Preserves functionality of current keys
- Limited Bluetooth range
- Connectivity issues reported by some users
- Potential installation difficulties due to door-specific constraints
- Requires separate purchase of smaller strike plates for some doors
- Limited compatibility with some hardware
- Weak Wi-Fi signal for some users
- Does not work with all double-cylinder deadbolts
- Compatibility: Works with various types of locks
- Auto-Lock & Home Sharing: Yes
- Battery Life: ~180 days
- Notifications & Alerts: Yes
- Voice Control: Siri, Amazon Alexa, and Google Assistant (requires SwitchBot Hub Mini)
Upgrading your existing lock system is made easy with this retrofit device. The SwitchBot Smart Lock works with your current lock setup and expands your home security without causing any disturbances. This handy device is compatible with a variety of lock brands and models, providing a simple and non-invasive enhancement to your home safety routine.
The effortless installation is pretty impressive as it works with multiple lock types, thanks to the provided 3M adhesive, which eliminates the need for tools. The SwitchBot Smart Lock doesn't require professional installation, making it one of the most user-friendly options available. You'll be able to enjoy improved security quickly and easily.
In a single-cylinder setup, the thumb slots into the SwitchBot device. For a double-cylinder setup, it's the key that slots in.
The SwitchBot Smart Lock also offers voice-activated control when paired with the SwitchBot Hub Mini, allowing integration with Alexa, Google Home, or Siri for smooth operation. Whether you want to control your lock remotely or just add more convenience to your smart home, this lock is an excellent fit.
An issue I did come across was reports from testers and device owners of inconsistent performance and the need for frequent recalibration. This could potentially impact your overall experience with the SwitchBot Smart Lock.
- Easy installation with no tools required
- Compatible with various lock types
- Auto-lock and home-sharing features
- Long battery life (approx. 180 days)
- ATS-128-CTR encryption for security
- Voice control via SwitchBot Hub Mini
- Occasional jamming issues
- May require recalibration regularly
- Some users reported early battery depletion
- SwitchBot Hub Mini needed for remote access (Additional cost)
- Limited to Bluetooth range without Hub Mini
Things to consider if you’re looking to smarten up your double-cylinder deadbolts
When considering security for a double-cylinder smart lock, you need to consider build quality.
For example, the Level Bolt Smart Lock not only offers a durable stainless steel build that exceeds industry standards but also integrates seamlessly with your existing deadbolt for additional protection.
Compatibility with Existing Doors and Hardware
Retrofit options, such as the Level Bolt Smart Lock and the SwitchBot Smart Lock, are designed to work in tandem with your existing lock infrastructure to provide a smooth and convenient transition to smart home technology.
These options are great for those who prefer not to change the overall appearance of their doors while still reaping the benefits of keyless entry and smart home integration.
It's also important to check that the smart lock you're considering supports the types of doors and deadbolts that are already installed in your home.
In the case of the Level Bolt Smart Lock, it's designed to fit most American standard deadbolts, making it a versatile and adaptable option.
On the other hand, the SwitchBot Smart Lock boasts compatibility with a wide range of different locks, ensuring a seamless and hassle-free installation process.
Integration with Other Smart Home Devices
When it comes to integrating a double-cylinder smart lock with other smart home devices, compatibility is key.
Before making a decision, ensure that the smart lock you are interested in can easily communicate with your existing connected devices or automation systems.
For example, the Level Bolt Smart Lock is compatible with Apple HomeKit, iOS, and Android, meaning it can work seamlessly with your iPhone, Apple Watch, or Android device. This also implies that the lock can be controlled remotely, and the user can manage access to their home through a smartphone app.
Another aspect to consider is whether the smart lock you choose can support voice control functionality through virtual assistants like Siri, Amazon Alexa, or Google Assistant.
For instance, the SwitchBot Smart Lock can be voice-controlled through Siri and Alexa, providing an added layer of convenience if you already use these voice assistants in your smart home ecosystem.
Additionally, some smart locks can be enhanced with extra devices and features, such as SwitchBot's Keypad Touch for fingerprint unlocking.
Ease of Installation and Setup
When it comes to ease of installation and setup, double-cylinder smart locks can range from extremely user-friendly to a slightly more involved process.
The Level Bolt Smart Lock offers convenience by allowing you to maintain your existing hardware, which means you won't have to replace door handles or keys. This smart deadbolt integrates seamlessly with your existing lock system, resulting in a fairly simple installation process.
All you need to do is replace the internal components of your current deadbolt, and you'll be up and running with a keyless entry system in no time.
On the other hand, the SwitchBot Smart Lock, which also retrofits to your existing deadbolt, requires no tools for installation and boasts compatibility with a wide range of lock types. With this lock, setting up the keyless entry system is as easy as attaching it to your door and connecting it to the SwitchBot app through Bluetooth.
While both of these products offer straightforward installation and setup, the SwitchBot Smart Lock is arguably the easier of the two when it comes to getting your new double-cylinder smart lock up and running quickly.
Battery Life and Power Options
When it comes to battery life and power options, one essential aspect to consider is how long your lock will remain functional without needing a battery replacement or recharge. For instance, the Level Bolt smart lock is designed to provide over a year's worth of battery life from a single CR2 battery.
|Level Bolt Smart Lock
|SwitchBot Smart Lock
|1 CR2 battery (included)
|2 CR123A batteries (included)
|Replaces existing deadbolt, adjustable backset (2-3/8” and 2-3/4” profiles)
|3M adhesive or drill
|Level app, voice control, auto-unlock
|App, Voice, Keypad Touch (sold separately)
|Yes (via Level app)
|Home Sharing feature
|Yes (via Level app)
|Requires SwitchBot Hub Mini (sold separately)
|Available with Keypad Touch (sold separately)
|Lock Status Notifications
|Yes (via Level app)
|Yes (with SwitchBot Hub Mini)
|Yes (via Level app)
|Over a year
|Approx. 180 days
How I Tested
For this article, I conducted extensive online research to identify which locks are compatible with double-cylinder deadbolts. This research involved reviewing the primary lock manufacturers' websites and product specifications, reading Reddit threads and other online forums where people with the same problem discuss solutions, along with checking out reviews of relevant smart locks from Amazon and other online platforms.
Well, that's my rundown of ways to add smart features to your double-cylinder deadbolt lock!
As mentioned, my main recommendation is the Level Bolt Smart Lock thanks to its low footprint, compatibility with Apple HomeKit, and keyless entry.
Let me know below, if you know of any other double-cylinder smart locks that I should add to this list.