Illustration: Jim Cooke

If you’re reading this article, you’re probably frustrated by the fact that, somewhere in your house or apartment, a smoke alarm with a dying battery is beeping, and beeping, and beeping—usually once every 60 seconds—but you cannot figure out where the alarm is located. The following solution to this problem will sound counter-intuitive, but it’s worked for me and others (Taylor Berman), so I’d like to share it with you:

  1. Stop trying to locate the alarm with your ears. Since you’re reading this article, this method has likely failed you already. So, for now, ignore the beeping and wherever you think it might be coming from.
  2. Pretend the alarm is an old wallet, or some other long-lost object that doesn’t make noise. That is, proceed as if the alarm could be anywhere. Rifle through everything. Your apartment might become a bit messy as you empty your drawers and cabinets. But you will find the alarm.

If you’re curious how this scintillating piece of advice came about, read on...

In December of 2013, about a year after I moved to New York, I found an apartment through a friend of a friend in the southern section of Bushwick, Brooklyn. The place was perfectly decent. It had four tenants (including me), a washer and dryer in the basement, a large adult cat that liked to climb on my chest while purring and drooling, a recently-renovated kitchen, and a five-minute walk to the J train.

It was initially hard to appreciate my new accommodations, however, because on the day I moved in, I noticed the apartment had a rather unusual feature: A loud and persistent beeping noise, almost like a chirp, emanating from the apartment’s main bathroom. It sounded exactly like the noise a smoke alarm makes when it needs a fresh battery. The strange thing was: There did not appear to be a smoke alarm anywhere in or near the bathroom.

From what I could tell, it—whatever it was—wasn’t attached to the ceiling or wall, or buried in any of the drawers belonging to the little rolling cart that carried our toiletries, or in the cabinet beneath the sink. But it was so loud. The smoke alarm had to be somewhere in there, right?

The situation’s weirdness quickly deepened. Each of my three roommates were aware of the noise, they told me, but had been stumped as to where it was coming from. When I asked how long it had been beeping, one of them responded: “Six months. Maybe longer.” They’d simply grown accustomed to the sound.

I prepared myself to admit defeat. The more I thought about it, though, the crazier the beeping seemed to be. If I couldn’t figure out where the beeping was coming from, I reasoned, then perhaps my sensory faculties were less reliable than I had thought. The fact that my roommates hadn’t been able to solve this particular mystery only heightened this strange sense of dread, the dread of experiencing an otherwise familiar phenomenon without being able to identify its cause.

The sound quickly became the only thing I could focus on when I was showering, or standing in the kitchen, or sitting in the adjacent living room. And then, one night, I started over. Treating this as a fresh but not unprecedented phenomenon, I looked at the ceiling. But there was no detector on the ceiling. No tiny red light. So I waited a minute to hear the beep again.

An hour or so later, I had still not found the source of the beeping. The walls? No. The hallway outside the bathroom? No. Inside the walls? No. (Perhaps I wasn’t looking for a smoke detector? I later found online references to beeping air filters, beeping water heaters, and beeping cell phone chargers.)

“We’ve looked everywhere,” one of my roommates told me. “Nobody can find it. I’m not even sure if it’s a smoke detector.”

I asked a tenant living in the apartment across the hall, whose bathroom shared a wall with ours, if he could hear the beeping from his own unit. He could not. He too tried searching our apartment for the beeping but, like me, became stumped after realizing that it seemed to emanate from the unoccupied space right above our bathtub, but beneath the ceiling—as if it were invisible, floating in the air, but still making that fucking beeping sound.

I hesitantly started Googling for answers. I say hesitantly because part of my frustration was that my otherwise trusty methods of investigation had failed me. The solution, like the problem, appeared simple: Just find the sound. Narrow down the possibilities. Follow your ears. Easy.

Searching for variants of “beeping,” “mysterious beeping,” “beeping behind walls,” and so forth, led me to stories like that of W. Carter Byrnes, who in 2005 became a minor media sensation after he complained, on an online forum for TiVo owners, about a frequent beeping in his Washington, D.C. townhouse, whose source he tried for years to locate without success. His story spurred dozens of strangers to show up at his property to see if they could locate whatever was making the noise. (It turned out to be an alarm clock buried in a drawer, floors away from where Byrnes thought the beeping was coming from.)

I did not intend to wait years. So I started looking for answers.

The online corpus of advice for finding hidden beeping objects is surprisingly wide, covering all sorts of situations. But it’s not very deep. Most advice boils down to: “listen harder” (and maybe also turn off the electricity for a few minutes to make sure the beeping is battery-based). If you were truly desperate, a Metafilter poster wrote in 2005,

I would [...] draw a map of my house to scale, then buy or borrow a decently sensitive digital sound recorder (some MP3 players have ‘em), and during the quietest part of the night, record the beep for a few minutes with the recorder in various parts of the house. Note on the map where the recorder was. Then, upload the recordings, and use a program to analyze the volume levels. This will give a whole lot of close numbers, like 67, 67, 68, 70, 65 and so on. Write these numbers on the map of the house, on the location where the recorder was when they were found. Head towards the higher numbers. Might take a few late nights to do it, but it should inevitably lead to the villainous noise. Unless the noise is moving around, of course.

I seriously contemplated doing this. But then I began to read about the technology, known as piezoelectricity, behind the specific kind of sound that smoke alarms make. The piezoelectric element embedded in most smoke alarms works by sending an electric charge through a piece of ceramic, which rapidly changes shape, producing sound waves—i.e., the loud beep you hear when a smoke alarm is activated. Or, in my case, when it requires a new battery.

A key feature of the piezoelectric element in smoke alarms is that its sound travels rather far, with little degradation to volume or frequency. This is a good thing: You want the beeps from an activated smoke alarm to seem as if they’re coming from every room in a building. But the very same feature can frustrate attempts to locate the alarm if it’s a) unclear where the physical device is located, and b) if the device is emitting not a constant death wail but a short, solitary beep every 60 seconds. What all of this means is: The beep of a nearly-dead smoke alarm is not always a reliable indicator of the alarm’s location.

This is particularly true for a setting like the bathroom of my apartment in Bushwick. All sound waves attenuate, or diminish, the further they travel from their source. But the degree of attentuation heavily depends on environmental factors. A December 2004 study about smoke alarm effectiveness that was commissioned by the U.S. Consumer Product Safety Commission noted that, “the least attenuated sound level would be in a small room ... [and] a soft room would have a higher attenuation factor than a hard room of the same size.” A soft room contains lots of soft surfaces, like upholstery, whereas a hard room contains lots of hard surfaces, like ceramic. And my former bathroom was both small and composed almost entirely of hard surfaces such as tile and glass. In other words, a sound that was already designed to travel as far as possible would, in a setting like my old bathroom, seem as it were coming from everywhere, or nowhere, at the same time.

So I closed my laptop and headed for the bathroom. I realized I had been far too cautious in trying to find the source of the beeping; when you’re the new member of any social setting, you don’t want to complain too much about, or work too hard to correct, something that everyone perceives but annoys only you. But at that moment, solving the mystery of the beeping had become more important to me than whatever social transgression I would commit in turning our common bathroom upside down, which I proceeded to do, at 11 p.m. on a Wednesday night.

It was in the cabinet beneath the sink, toward the very back, obscured by a rather large canvas bag of sand. The bag’s color (dark gray) and shape (or lack thereof) had blended very well into the back of cabinet, whose interior and exterior were painted black, while its weight had made it seem like nothing else was there.

After bringing the smoke alarm into the living room, I removed its battery, and the beeping ceased. Then I texted one of my roommates:

We never figured out where the bag of sand had come from, or why someone had placed a smoke alarm beneath it. But if I were to guess, my guess would be this: Someone who used to live in the same apartment had placed it there because he or she had been trying to cook an elaborate dish in the kitchen, which was right next to the bathroom, but kept setting off the fire alarm with the cooking fumes. Placing the alarm in a different room, within a cabinet, under a heavy bag of sand, would have almost certainly prevented the smoke alarm from detecting those fumes.

The relief I felt at finding the alarm was tremendous. It quickly diminished, though, when I began talking about writing this article during a pitch meeting the next week, where most of my coworkers regarded the idea of this piece with undisguised derision, then proceeded to make fun of me for it, off and on, for the next three years.

For example:

Anyway: That’s how I found a beeping smoke alarm when I didn’t know where it was. With my simple method, hopefully you can, too.