Why there aren’t any smart double cylinder locks on the market

There’s a reason people want to equip their homes with double cylinder locks. These locks require a key to lock or unlock the door both from the outside and the inside, making them a little safer, in one regard.

For example, if there’s a window on or nearby the door – think of sidelight windows next to a door, for example – someone could break the window, reach in, and turn the deadbolt of a single keyed lock. With a double cylinder lock, they’d still need a key in that case.

So why aren’t there any smart double cylinder locks on the market?

That’s the question we received on the IoT Podcast hotline in our last episode from Scott. It’s a good question and the answer also relates to safety, but not from the outside of your home.

In the U.S. many fire codes actually don’t allow for double cylinder locks for a home’s entry door. The reason is that if you have to leave the house quickly, such as in a fire, it requires a key to unlock the door and flee the fire. What happens if you can’t find or reach the key in an emergency such as that? Nothing good of course. Sure, you can leave your key in the lock from inside the house to mitigate this, but if someone breaks a window near the door, they can turn the key as if it were the deadbolt on a single cylinder lock.

As a result, it’s really not in the interest of smart lock manufacturers to design and build a smart lock that works like a double cylinder device.

I suppose it’s possible that a lock company could eventually offer one with a keypad both on the inside and outside of a connected lock. After all, there’s no physical key to find in case of a fire or other emergency. But it’s still a potentially risky situation: If you’re facing fire or some other home emergency, will you be able to focus your mind in a life-or-death event and clearly remember your keypad code?

To hear Scott’s question in full, as well as our discussion of the answer, tune in below to the IoT Podcast: