Smart lock: physical security for the interior side?

I am considering fitting a smartlock to my porch door so that packages can be delivered and left in the porch. Once the delivery has been made, I can lock the door remotely via ST and check the porch on my camera to see the delivered item. Unfortunately, my porch door has clear glass windows and the letterbox is quite close to the existing lock mechanism (see image). My concern is that most of the smart locks that are compatible with ST and my existing lock seem to have a thumbturn handle on the internal mechanism that allows the door to be opened. What is the possibility of someone activating the unlock handle using a device fed through the letterbox? As the door is also glass it makes it even easier for them to guide it. If the the internal handle could be deactivated but still retain remote lock functionality then great. If not then is there a flaw with using a smartlock in this situation? I contacted Yale UK with regard to their conexis L1 and my situation above and they haven’t provided an answer.! Traditional locks are fitted to the house doors, I only want to control access to the porch. image|666x500

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The internal thumb turn is typically mechanically linked to the lock to maintain normal operation. If the lock batteries die, the thumb turn / a key is the only way to open the door. There’s a possibility you could remove that lever but if the batteries die and there’s an emergency situation you’re potentially trapping someone in the house.
Do you have a lock now or would the lock be a new addition? If there’s already a lock, how are you addressing the concern now - is there nothing in your porch worth stealing besides packages? Are you considering a deadbolt or a lever? If you don’t have much other security concern, a lever such as Kwikset 912 might give you more comfort, as the thumb turn is much smaller and would be difficult to manipulate with a tool such as a coat hanger (I think a deadbolt would also be tricky to get through this way but it’s at least more plausible than the lever).

What country are you in?

In both the US and the UK, in most buildings where people sleep, there is a fire safety requirement that all doors that give access to the outside must be able to be opened without requiring a key or “any special knowledge.” (Which means no lock codes.)

However, other countries, including Australia and several in South America, do not have this requirement. This is why you will see residential locks that require a key on both sides in some countries but not others.


In the last 10 years or so in both the US and UK there has been rising interest in ways to keep children on the autism spectrum and adults with dementia from being able to let themselves out at night while still meeting the safety code.

One of the simplest would meet your requirement as well: simply put a small box cabinet over the interior lock. Put the opening mechanism on the side away from the letter box and it should be very difficult to get open from the letterbox. :sunglasses:

You can make a custom box pretty easily, or you may be able to find one readymade if you check places that sell childproofing equipment for families with “wanderers.” Depending on the size of the lock, you might also be able to use one of the plastic boxes designed for thermostats or outdoor receptacles.

Also, I should mention that in your case you probably don’t want a standard “confounding lock.” This in an interior side device that requires physical manipulation to open, usually a lift and twist. The problem with these is that you couldn’t let the deliveryperson In with the confounder In place and they couldn’t put it in place when they left. But the box cabinet doesn’t have that issue.

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Another option is a mail receptacle on the inside:


I’m trying to work up the courage to try a Haven lock: It’s a bar-like device that gets installed just inside your door’s threshold and supposedly is much more secure than a deadbolt. Because its mounted on the floor, smashing the glass is less of an issue. They have a bluetooth connected version but I’m not sure if/how it can be connected to SmartThings.

And of course there is the obvious… It’s a glass door. If they want in, a glass punch does the trick quite nicely. Don’t overthink it.


Haven doesn’t integrate with smartthings. But I agree there’s absolutely no point in putting one on a glass door, they’ll just smash the glass and step over it. So you don’t even get the tamper alert that you might get from other types of smart locks. It’s also much more expensive.

Haven is intended for people who live in places where the back door gets kicked in with three or four kicks. Haven says it will withstand up to 50 kicks. But I’m betting your glass door wouldn’t. :wink: or the window around the side.

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Yeah, makes sense. My door is only half glass so it would be a stretch for an intruder to reach all the way down to release it. But even so, if they want in, they’ll get in and the lack of ST compatibility is a bummer.

I’d be curious to hear what folks are doing for half-glass doors that afford access to the lock via a broken glass pane in the door. Anything that works there would work for OP as well. The lock enclosure is one idea but not sure I could pull it off in an aesthetically acceptable manner.

If it’s a half glass door and they break the glass part can’t they just climb in that way, like a window?

Its 9 small panes. They can smash all of them plus the frames with some effort but it would be much easier to smash just one and then reach inside to open the lock.

In that case, you just put extra frames or mesh on the inside of the glass. That’s what people do in very high crime areas. There are many styles of these.



However, if they’re doing that, they likely also have similar barriers on the windows. Because it’s fairly rare for a typical US suburban burglar to consider a locked door the weakest point of entry. They’ll check the door to see if it’s unlocked or if the lock is an easy one to open, but then they’ll just move on to a window.

Haha! My father-in-law suggested the same thing! We haven’t found “nice” ones yet but we’ll keep looking.

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Figured if someone wants in, they’ll get in. I do have 2 glass break sensors if someone does decides to break the glass to easily turn the locks…Don’t give it much thought though.

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