Pulling the Thread to know if my garage door is closed

I had a simple task that involved Apple Home. If you use Apple Home, you know what happened next. Tears, frustration, the arrival of batteries, paperclips pushed into hard-to-reach holes, many online searches, and—if you are lucky, as I was—success.

Siri, am I lazy?

My goal was straightforward: can I know if the garage door is open without going to look? Early in the pandemic, we occasionally forgot to close it. While there was a locked door between the garage and the house, it still felt like we were playing with fire, as someone could steal a bike or other lesser goodies from the garage.1 The garage is on our basement floor (ground level on one half of the house), and the last thing I enjoy doing at night is walking downstairs before bed to check the door.2

I purchased an Eve Door & Window Contact Sensor to have this capability reported by Apple Home, joining a growing set of HomeKit devices, including our front-door deadbolt. Because of our old-style single-piece swing-up garage door, I had a heck of a time finding the right place and right adhesive to stick the sensor where it was close enough for the two components to register.

The red-on-pink Characteristic is Shortcuts tells me it couldn’t read anything back from the sensor.

I spent enough time on the vagaries of physics and materials that I was probably more frustrated than I needed to be when I tried to make a workflow with the danged thing. An Automation wouldn’t work because I wanted an alert, not for the sensor to trigger other Home devices. A Shortcut should have worked, but after many hours of trying over weeks, I was unable to get anything reliable to happen. The Automation was quite simple: at 9 p.m., check the state of the sensor, and send me a message if the sensor shows Open rather than Closed. I left it in place and walked away for literally years.

After recently installing a back-driveway camera, I was determined to get this sensor online.3 First, I replaced the battery, which had died during my period of disinterest. The Eve sensor uses a weird, tiny battery: a 3.6V 1/2 AA (ER14250). After that arrived, using some better adhesive—thin-film 3M 468MP—I positioned the sensor pieces in a better location and more securely.

Now it should work! Except that after adding it, I saw Characteristic in red text on a pink background in Shortcuts. Some online research led me to reset the sensor by inserting a paperclip into a hole I hadn’t noticed. After re-pairing the sensor, I was in business! Or was I?! The sensor wasn’t responding, despite recent status updates.

Threading the sensor through the house needle

The working Shortcut tests for the garage door sensor‘s state being Open or Closed, and acts accordingly.

This led me to the next culprit: the garage is too far away (one floor and the other end of the house) from my Apple TV, which acts as a Matter controller, while the Eve sensor relies on Thread as its communication protocol. What’s a Matter controller?4 And what’s Thread?

Matter is an overarching standard, painstakingly developed even as low-power sensing devices and other equipment proliferated in silos. Matter enables Amazon Alexa, Apple Home, Google Home, and Samsung SmartThings devices to communicate across a network, regardless of the network transport medium (Ethernet, Thread, or Wi-Fi). This prevents you from needing ecosystem-specific hubs and lets manufacturers build to a common standard.

Thread fits into this mix as a low-power, wireless networking standard for sensors, allowing them to communicate their status without rapidly draining their batteries, as would happen with Wi-Fi.5 Apple initially supported Thread with a proprietary standard, HomeKit-over-Thread, and later added direct Matter support. The Eve sensor was just old enough that it was running on the older standard, but the Eve app allowed me to apply a firmware upgrade. I could then migrate the sensor to Matter, which seems to be more reliable.

Apple made things a little confusing here, too. The 1st-generation Apple TV 4K supports Matter, but lacks a Thread radio, so it can’t work with Thread-based devices. The 2nd generation added that radio, so you can do Matter over Thread. But then, with the 3rd generation, Apple bifurcated Thread hardware support: the 64 GB Wi-Fi only model lacks a Thread radio; you have to spend the now-whopping $249 for a 128 GB Wi-Fi + Ethernet version if you want to use Thread.

Failing an Apple TV 4K with Thread, you can use a Thread border router (TBR), which sometimes comes with sensor kits. This plugs into your network via Wi-Fi or Ethernet and bridges to the Thread network, allowing the Apple TV’s Matter controller to work with the Home app on your devices for automations, notifications, and so forth.

It’s that easy, folks. Sigh.

I do own a 3rd-generation Apple TV 4K with Wi-Fi + Ethernet, because I am a fancy man and a big spender, but I really wanted the reliability of plugging it into my Ethernet network. Yet, I couldn’t get the Eve sensor’s Thread radio to reach across my house to talk to the Apple TV. I bought a TBR, thinking it would solve the problem.

By the time the TBR was delivered, however, the garage door sensor magically connected via Thread to the Apple TV and has been rock solid. The TBR that arrived, on the other hand, I was unable to pair and get working, so back it goes for a refund.

Now my nightly Shortcut works! The only fly in that ointment is that the sensor status reports as Closed or Open in iOS and iPadOS, but as 0 (closed) or 1 (open) in the macOS Home app, in both macOS 26 and the beta of 27. I can live with running the Shortcut from my phone.

Shortcuts in macOS can’t seem to read the Home sensor’s text labels of Open and Closed, seeing 1 and 0 instead.

[Got a question for the column? You can email glenn@sixcolors.com or use /glenn in our subscriber-only Discord community.]

Bikes were in short supply and sold at outrageous prices in the early pandemic, partly because supply chains to import new ones were halted. Then, there was a glut when life allegedly returned to normal. ↩

I mean, I don’t enjoy doing it as the final thing of the evening. English is complicated. The last thing I enjoy doing before bed is some crossword puzzles while listening to a podcast. ↩

I immediately discovered a family of bandits! ↩

I don’t know. Whatsa Matter controller, you? ↩

Technically, it uses IEEE 802.15.4, the same as the delightfully named ZigBee. ↩