Should You Close Air Vents in Unused Rooms in the Winter?

Many homeowners think it’s a good idea to close air vents in unused or infrequently used rooms during the winter months to save money on heating. Should you do the same?

The short answer is no.

As a matter of fact, doing this can lead to the need for a home furnace repair. Here’s why closing those vents during the winter season is a bad idea:

Furnaces and the ductwork that distributes warm air aren’t one-size-fits-all. They’re designed for the specific square footage of the home in which they’re installed. The distribution of air through the system is disrupted when vents are closed.

The room still has a working return air vent that pulls air out from the space. Pressure will build up if the return vent can’t get cold air. This will cause cold air to be sucked out from the gaps around the door and windows, as well as through cracks in the wall or ceiling. Your furnace then must work twice as hard as it attempts to warm the room.

Closing air vents can lead to a drastic change in the room’s temperature. This is bad for wood furniture, as it can cause warping. Ice may also start forming on the room’s windows. Moisture that gets in the gaps and crevices will freeze and expand, forcing those openings to enlarge. In addition, if the room has vinyl floors, low temperatures can cause them to crack.

Your furnace is designed to keep your entire house warm. Closing the air vents in some rooms means those rooms will have freezing temperatures that affect the entire house. This will force your furnace to work harder and longer to combat the cold coming from those rooms. This means it uses up more energy, which you’ll see on your next bill.

If the furnace breaks, you’ll be paying a lot more for an ill-timed furnace replacement. Before your furnace can be replaced, you’ll have to deal with a freezing house.

Instead of completely closing the air vents in unused rooms, you can save energy with these alternatives:

If your home has a second story, you can partially close your upstairs vents. Heat naturally rises, so your furnace can still maintain a balanced level of warmth around the house.

Close all gaps, cracks and crevices around your windows and in the walls. Hire a pro to apply caulk, sealant, weatherstripping and other weatherproofing materials.

Have your furnace maintained at least every two years to keep it working optimally. Clean and reseal the ductwork wherever necessary.

Increase the insulation in your attic and make sure the ventilation system isn’t blocked. Never cover your attic vents, as this will prevent moisture from leaving your attic, leading to water damage.