New York City’s Local Law 157 is coming. By May 1, 2025, every apartment with a gas appliance will need a natural gas detector. Seems straightforward, right? Just slap a detector on the wall, and you’re done. But if you’ve ever dealt with NYC building laws, you know there’s always more to the story.

Why Local Law 157 Exists

A few years ago, there were two major explosions from gas leaks in NYC buildings. In response, the city’s reactionary building codes kicked in. Enter Local Law 157, a well-intentioned mandate to prevent future disasters.  

But here’s the thing: these detectors are different than your average smoke alarms that just emit a high pitched sound. When they detect gas, they blare a message to scare people into action:  

“Danger. Gas leak explosion risk. Evacuate, then call 911.”

Sounds like a solid safety measure, until you realize this alarm could have some unintended consequences.

The Domino Effect of a False Alarm

Picture this: a pilot light goes out in one unit, a tenant hears the alarm, panics, and calls 911. The fire department arrives, shuts off the building’s gas as a precaution, and now your whole building has no gas service. Here’s the problem: getting gas turned back on isn’t as simple as flipping a switch.  

In most cases, the entire gas system has to pass a pressurization test. Unfortunately, older NYC buildings rarely pass without expensive, months-long re-piping work, followed by months of waiting on city inspections and certifications. This means millions of dollars and unhappy tenants who suddenly have no heat, hot water, or working stoves for many months, or even several years. -No exaggeration, this happens more often than you'd like to think.

Your Two Options: Dumb vs. Smart Detectors

So how do you avoid having Local Law 157 turn into an enormous problem? It comes down to choosing the right type of gas detector.  

The Dumb Detector

• Simple, standalone devices you can buy on Amazon.  
• They comply with the law and will alert tenants when they detect gas.  
• They also ensure 911 gets called, often unnecessarily.

The Smart Detector

• Alerts management immediately via text or app when it detects gas.  
• Gives staff a chance to investigate before tenants panic and call 911.  
• Can prevent unnecessary gas shut-offs and save you millions in re-piping costs.  
• Bonus: Includes a temperature sensor to optimize heating and cooling systems.  
• Extra Bonus: Can be included in projects that receive utility rebates, helping to cover the costs.

Why Smart Detectors Make Sense

Smart detectors are a game-changer. Instead of leaving tenants to deal with a blaring alarm on their own, these devices notify management within seconds. That means your super or property manager can address the issue—like a pilot light being out—before things escalate to emergency calls and gas shut-offs.  

Even better? If your building already uses Runwise, these detectors integrate seamlessly. No new networks, no extra hassle

Want to learn more?

Fill out this form on this page. We'll send you information on all your options and check to see if your building qualifies for a rebate to help cover the cost of the gas detectors.