How I Made My Old Buzzer and Siri Best Friends — in 10 Minutes

It all started with something simple — last summer, right after celebrating the Fourth of July, I lost my key to the common building door. It didn’t seem like a big deal at first, but that’s how the whole story began. What followed was nearly two months of waiting for my HOA to get around to making me a new one. During that time, every trip to let someone in felt like running a marathon — juggling groceries, carrying my kid, or trying not to get drenched in the rain.

In the middle of all those sprints, I had an epiphany: why am I still living like it’s 1985? My apartment already had an intercom with a "Door" button, and my phone already listens to me. So, why not connect the two and just say, "Hey Siri, open the door"?

The Search

I started looking for a way to make it happen. The solution had to be small, reliable, and smart — something I could easily hide behind the intercom panel. It needed to work with 2.4 GHz Wi-Fi, have a simple API, and be fast enough to open the door with no noticeable delay.

I found the right relay, powered it with a 12V DC adapter, and connected it to my Wi-Fi. No messy wiring through walls — just plug it in, connect it, and it's ready to work.

Making the Connection

The next step was wiring it into my existing intercom. I won't go into every detail here — that's all in my DIY PDF — but it came down to adding the relay in parallel with the "Door" button. That way, the button still works exactly like before, but now Siri has a way to press it too.

Teaching Siri

With the relay online, I used its API to create an iPhone Shortcut. Now, when I say "Hey Siri, open the door," my phone sends a quick command to the relay, and within a second, the buzzer clicks open. It works from my Apple Watch, lock screen, or even automatically when I get home.

The Result

Now, I can open my building's door without running to the intercom, without keys, and without even being inside. It's a small change, but it's one of those upgrades you use every single day and wonder how you lived without.