The short answer?
Yes. It's OK to close air vents in unused rooms.
But there's still plenty to be cautious of before you begin trotting around the house with a stepladder:
- Don't close too many off. If you shut too many registers, you're seriously restricting the air flow of your home or apartment's entire system. Experts recommend closing off no more than 40 percent of your home. Do less, to be safe.
- Make sure there's no thermostat in the areas of the house you're closing off. If there's a temperature gauge in there, you're going to throw the whole system off balance. In winter, for instance, a super-cold closed-off room might be telling your heater to max the gas and heat up the whole (already warm) house.
But if you do it right, closing an air vent or two will definitely help save on heating or cooling costs—and it might even help keep the other rooms in your house warmer or cooler, too!