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Halo+ Smart Smoke & Carbon Monoxide Alarm review: This lesser-known smoke alarm keeps up with the Nest Protect, warns you of impending weather

The Halo+ actually manages to make weather alerts on a smoke detector feel worthwhile.

Andrew Gebhart Former senior producer
6 min read

Editors' Note, July 30th, 2018: Halo Smart Labs has gone out of business. You will no longer be able to buy the Halo+ Alarm and Halo will be discontinuing app support. See the details of the announcement here. The earlier version of this story follows. 


Halo+ Smart Smoke & Carbon Monoxide Alarm

The Good

Halo+ adds customizable weather alerts and a color-changing nightlight to an otherwise competent smart smoke and CO detector. The Halo+ works with Amazon’s Alexa, SmartThings, and Lowe’s Iris.

The Bad

Since it doesn’t detect motion, Halo’s light won’t turn on when you pass under it at night. Silencing the alarm with the app takes too long.

The Bottom Line

Yes, the weather alerts are redundant with your phone, but Halo+ implements the feature well enough to be worth your consideration as a Nest Protect alternative.

By adding weather alerts to a smart smoke protector, the Halo+ skirts a fine line between useful innovation and annoying add-on. Fortunately, the first product from startup Halo Smart Labs implements the feature well enough to land on the good side of that line.

The $130 Halo+ Smart Smoke & Carbon Monoxide Alarm with Weather Alerts does all of the basics you'd expect of a smart smoke detector, and it thankfully adds weather alerts with enough customization that they're more helpful than bothersome. The $100 Nest Protect is still the best smart smoke detector out there, but the Halo+ is a worthy competitor that I'd recommend if you live in an area with dangerous weather -- especially if you like turning your phone off at night.

The Halo+ guards you from inclement weather as well as smoke

See all photos

What's up with those weather alerts

You might be wondering why on earth you'd need your smoke alarm to tell you that it's raining out, especially since you have a smartphone and a pair of eyes. Rest assured, the alarm won't start blaring at full volume every time it sprinkles.

Install the alarm -- it's hardwired with a battery backup -- and you'll use the iOS or Android app to connect it to your Wi-Fi. During setup, you'll choose which weather events you want to be notified of, and you can make changes in the future as you see fit.

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You have lots of options to help you customize your weather alerts.

Screenshots by Andrew Gebhart/CNET

I appreciated the level of detail in the setup, as you can even decide that you don't care about a tornado watch, but if it gets to be a tornado warning, then you'd like to know. Check out the picture above for all of your options.

When the weather does get dangerous, the alarm still won't start blaring. Instead, Halo+ tells you what's going on with a voice alert and tunes to the local weather station of your choice. I like the feature as a natural extension of the smoke detector as a safety device. Yes, it's somewhat redundant with the emergency notifications on your smartphone, but with Halo+ you can rest easy if you want to turn your phone off at night.

If you just want a smart smoke detector without weather alerts, you can buy the Halo Smart Smoke & Carbon Monoxide Alarm (without the plus and thus without the weather feature) for $100. Both the Halo and the $130 Halo+ are available on the company's site, as well as Home Depot, and Lowe's. Both products are US-only for now.

It detects smoke, too

In addition to giving you an audible warning in the event of a hurricane or a flood, the Halo+ is certified as both a smoke and carbon monoxide detector (specifically, it conforms to UL standards 217 and 2034).

Halo uses both an ionization detector and a photoelectric sensor to detect smoke. Head here for a detailed breakdown of how those two sensors work. In brief, Halo combines a quick trigger alarm with a slower, smarter alarm.

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Halo picked up smoke and sent alerts quickly in our tests.

Chris Monroe/CNET

The Halo+ combines the two to good effect -- it reliably picked up smoke quickly in our tests. We used smoke candles and an ordinary First Alert hardwired alarm for comparison. The First Alert detector sounded its alarm first every time, but the Halo+ was never more than a couple of seconds behind. That test lined up with our results from the Nest Protect.

The Halo+ even delivered its push notifications slightly faster than the Nest Protect did. The exact speed of the alerts will depend on your internet connection, but during our testing, Halo+ delivered it's alerts immediately after the alarm itself started to sound. The Nest Protect took a couple of extra seconds.


Notice the amber light when Halo only smells a little smoke vs the red color when it smells a lot. Halo makes you play the game on the right to silence the alarm. 

Screenshots by Andrew Gebhart/CNET

In both its push alerts and its audible warnings, Halo differentiates between a little smoke and a lot of smoke. As with weather notifications, the Halo+ will tell you what's wrong with a voice notification and tell you the location of the sounding alarm as well. We assigned ours to the basement, so the alarm told us it smelled smoke in the basement, then started the traditional smoke alarm siren.

As the alarm sounds, the built-in accent light flashes as well -- amber in the case of a little smoke, red for a lot of smoke or carbon monoxide, and blue in the case of a weather event.


Use the app to test the alarm, change the color of the accent light, and see a log of activity. 

Screenshots by Andrew Gebhart/CNET

Using the app, you can silence the alarm, but the Halo+ has a safeguard built-in stopping you from doing this if it detects a lot of smoke. You also have to be in sight of the alarm to silence it, as the alarm's light changes color three times, and the app asks you to identify each new color before it'll shut up. In practice, I'd like to be able to silence the alarm a little more quickly, but I appreciate the caution Halo takes with the feature.

Outside of an emergency, you can use the app to test the detector, check the battery, and see a log of recent alarm activity. You can also change the color and brightness of the accent light. The light offers a couple of timers so you can set it to turn off after 15 or 30 minutes, and it has effects called "Party Mode" and "Rainbow" which change its color quickly or slowly.


You can change the color and brightness of Halo's accent light.

Chris Monroe/CNET

I highly doubt Halo's Party Mode will get much use beyond showing it off as a novelty when you first buy it. I'd much rather have Nest Protect's feature where the light turns on when you pass under it at night. Aside from those unnecessary but harmless extras, I liked the accent light and found the app easy to use.

Still not as smart as Nest

The Nest Protect gains a significant edge over the Halo+ if you want to include it as part of a larger smart home setup. First and foremost, the Protect works with other Nest products like the Nest Cam so you can automatically record the action when the alarm sounds.

The Protect also works with online rule-maker IFTTT, allowing you to set up recipes tying the Protect to a wide range of smart home products. For example, you can flash your smart lights in an emergency. Beyond that, the Protect has a host of other integrations, thanks to Nest's widespread smart-home platform called Works with Nest.

Thankfully, Halo didn't come to the smart home empty handed. You can test your alarm or change the color of the accent light with your voice by way of Amazon's digital assistant Alexa (unfortunately, you can't silence the alarm with a voice command). Activate the Alexa skill, and you can control your Halo+ with a voice command to Amazon's always-listening speaker, the Amazon Echo

You can also connect Halo to larger smart-home setups with IFTTT, SmartThings and Lowe's Iris. Similar to the Protect's connection with IFTTT, you can set up rules with SmartThings, Iris or IFTTT to flash compatible bulbs when your alarm sounds.

The verdict

Granted, the most unique feature of the $130 Halo+ is a redundant one with any ordinary smartphone, but if you live in an area that's prone to inclement weather, I'd still call the weather alerts handy. Plus, the feature is well implemented and the Halo+ otherwise gets the basics right. Go with the Nest Protect if you're just interested in smart smoke detection, but if you want your smoke alarm to help you keep an eye on the sky, the Halo+ is worth your consideration.


Halo+ Smart Smoke & Carbon Monoxide Alarm

Score Breakdown

Features 8Usability 8Design 8Performance 9