Would It Be Possible to Crawl in Vents Like in Movies?

June 6, 2022

Movies and TV shows often depict characters crawling through air vents to escape danger or access a hidden area. But is this possible?

It turns out that crawling through vents is not as easy as it looks on screen…

Small Size

For one thing, most vents are much smaller than they appear in movies and TV shows. Of course, you probably already know that the vents in your home or office are probably not big enough for a person to fit through, but even industrial vents can be smaller than you might expect.

For example, for “round metal pipe” ducts, they range anywhere from 5 inches to 20 inches in width. For rectangular ducts, the smallest are only 6 inches wide and 4 inches tall, and the biggest are 42 inches wide and 12 inches tall. There are occasionally ducts that are up to 30 inches tall to blast a large CFM (cubic feet per minute) of air through them, but these are rare.

No connection

Let’s say you’ve been lucky enough in your secret-agent pursuits to find a large enough duct to crawl through. Your next problem is that the typical duct system does not directly connect different rooms. Instead, the ducts are all connected to a central location called a plenum. The plenum is usually located in the attic, basement, or utility closet, and it’s where all the ductwork for the building comes together. There can be exceptions to this rule, but they are rare. So, the idea that you can use a duct system to get from Room A to Room B without running into a dead-end is not very likely!

Painful mission

Additionally, most vents are not designed to be climbed through. They usually have sharp edges and corners that can cut or scrape you. Then you’ll yell out and be caught by whoever’s down below! That’s another thing – the Mythbusters tried crawling through a vent and found that it was deafening.

Too loud

Have you ever been in an old building and heard the loud booming and popping noises as air moves through the ducts? Yep, and that’s just from the air. Imagine a human tromping all over galvanized steel or fiberglass. No matter how stealthy you think you are, Mr. Bond, unfortunately, there is no way you won’t be heard. When the MythBusters tested this out, the noises of a person moving through the vents could be heard even several floors above or below.

While we hope we haven’t completely dashed your movie-inspired dreams, the bottom line is that unless you’re a tiny child or have access to some heavy equipment, it’s probably not worth trying to crawl through vents.

When it comes to the air going through the vents, that should always be flowing smoothly and nice and cool! If you have any problems with leaky ductwork, poor airflow, or an AC not cooling properly, give us a call. We’ll be right over to your Phoenix or Tucson home (and don’t worry, we won’t try crawling through your vents).