Should You Close Vents in Unused Rooms? Experts Explain Why It Could Backfire

Experts are weighing in on one of the most common energy-saving habits, and their verdict may surprise homeowners. Here's why keeping those vents open could be the smarter move for both your wallet and your HVAC system.

At a time when most people are watching their spending, it's only natural to look for ways to save, especially with the colder months approaching. However, closing the vents in seldom-used rooms isn't one of them.

It may seem counterintuitive at first glance, but there are several reasons why shutting vents doesn't make sense, even in rooms you rarely use.

"Contrary to a common misconception, closing vents in unused rooms can create pressure issues for your system, forcing it to work harder and potentially leading to damage," says Micah Sherman, virtual HVAC expert at American Home Shield.

The science is fairly straightforward. The volume of air that moves through an HVAC system each minute, measured in cubic feet, has to be returned to the system. Closing off vents disrupts that airflow.

"The air ends up building up at those vents and causes extra pressure, which can actually damage your system," explains Eli Zimmer, director of operations at Luxaire HVAC Services. "Your system may actually work even harder to try to get air through those vents, amplifying the pressure and becoming a hazard."

Beyond the pressure buildup, closing some vents can cause leaks in the ductwork and connections, as well as uneven temperatures throughout your home. Over time, you could face even higher bills, damaged ducts, and costly repairs to the blower motor or heat exchanger.

The general advice is to keep every vent in your home open. However, if you'd like to close off certain sections, Tim Algaushove, COO at IRBIS Air, Plumbing & Electrical, recommends consulting an HVAC technician about installing a zoned system.

"When set up properly," he says, "HVAC zoning can help you control specific areas of your home independently from each other. Your HVAC provider can also help you understand how to use this type of system efficiently and achieve your specific goals."

Still, Keith Wortsmith, president at Dash Heating, Cooling & Plumbing, maintains that the rule holds firm. Even in homes with zoned heating, he notes that closing vents typically isn't necessary, since the system is designed to handle that automatically.