4 Methods to Close That Ice-Cold Ceiling Vent (Home / Office)

Is the ceiling vent in your home or office giving you the cold shoulder?

It can be a little tricky to see how to close every type of ceiling vent. But we’ve got you covered.

How to close a ceiling vent depends on its shape and type. Generally for a circular vent this is in the center, but rectangular or square vents have dials on one side. If you can’t get it to close, covering ceiling vents with some insulation can help in winter.

That being said, there’s more details than that (depending on your type of vent).

Read on, and let’s stop that cold vent air from spoiling your cosy afternoons.

How to Close Any Ceiling Vent

Can you feel an unpleasant draft coming from your ceiling vent? If you’re sitting for hours on end under a ceiling vent at work or home, the last thing you need is a gale-force wind constantly blowing down your neck. So what can you do to close a chilly ceiling vent?

Take a look at the steps below that will help you to close any vent in next to no time. The only tool you’ll need for this job is a step ladder.

Method #1 Rectangular Vents

A rectangular ceiling vent typically operates with a switch. You can move this switch up or down to open or close the vent. If you would like to close a rectangular vent, do the following.

  1. Use a step ladder to safely reach the vent
  2. Slide the switch on the vent up or down to stop the air from flowing through
vent in ceiling with switch
Slide the switch up or down to stop the airflow

Method #2 Circular Vents

A circular ceiling vent is usually installed with a dial. The dial when turned can open or close the flow of air. Here’s how to close a circular vent in your home or office.

  1. Use a step ladder to safely reach the vent
  2. Turn the dial on the vent anticlockwise to stop the flow of air

Method #3 Square Vents

Square ceiling vents operate very similarly to circular vents. They also have a dial that you can turn to open or close the flow of air. To close a square vent, here’s what you should do.

  1. Use a step ladder to safely reach the vent
  2. Turn the dial on the vent anticlockwise to stop the flow of air

*NOTE: The dial on the vent could be located underneath the vent cover. If it is, you will need to remove the vent cover to close the flow of air. On some vent models, you can pull on the cover to remove it and expose the dial. On others, you will need to use a screwdriver or a drill to remove the cover.

vent in ceiling
The dial could be underneath the vent cover – a screwless model like this one can just be popped off.

Method #4 Other Vents or Covers

So what can you do if you cannot see a switch or a dial on your ceiling vent? Don’t worry, you won’t have to settle for sitting at your desk with a turtleneck sweater and a jacket on all year round. There is an easy and inexpensive method that you can use to close it.

You can also get magnetic vent covers which will also do the job.

Here are the tools you will need for the job.

You Will Need

  • Step Ladder
  • Marker
  • Utility knife or scissors
  • Thin sheet of insulation (rigid foam board only – not other types)
  • Drill or screwdriver (depending on your vent)
  1. Use a step ladder to safely reach the vent
  2. Use the marker to mark the size of the vent on the insulation
  3. Cut the insulation to the size of the vent using a pair of scissors or the utility knife
  4. Take the front cover off of the vent. If your vent cover isn’t fixed in place with any screws, you should be able to pull it off easily. If not, you will need to use a screwdriver or drill to remove it.
  5. Place the sheet of insulation over the front of the vent
  6. Fix the vent cover back into place
removing vent cover
Remove the vent cover using a drill or screwdriver

Can You Block An Air Vent?

There are a lot of factors to consider when it comes to blocking air vents at home and in the office. Blocking the vent could provide you with momentary relief from a pesky draft. But perhaps you are wondering what the long-term effects are of closing up an air vent. That’s why up next, we will consider the effect of a blocked air vent on the following:

  • Your utility bill
  • The airflow in the room
  • The temperature of other rooms in the house or office

Your Utility Bill

Will blocking the air vents in some of the rooms you’re not using cut down on your utility bill? You could reason, if you’re not using the room, you might as well block the vent to stop you from paying to cool that room.

But how does it really work?

When you block an air vent, your utility bill will not decrease. This is because the air that was meant to flow through the blocked vent will be forced into the next available one. And the more vents you block, the further the air will travel to circulate around open vents in the house.

Rather than decreasing your utility bill, blocking some of the air vents could make you pay more. This is because your ventilation system will try to work harder to heat and cool the rooms with blocked vents. This means your heating or cooling will cycle on more often than it would if you were to keep all the vents open.

The Airflow of the Room

How will blocking the vents affect the airflow in the room?

Well, with the vents closed, your ventilation system will not be able to pump fresh air from outside into that room. Instead, the room with the blocked vents will be relying on recirculated air. This could be an issue in office environments where having a constant flow of fresh air is essential.

To enjoy a steady stream of fresh air in a room, you will need to keep the ceiling vent open.

checking for airflow in vent
For a constant flow of fresh air, keep the vents open

The Temperature of Other Rooms in the House or Office

So how does blocking a ceiling vent affect the temperature in the other rooms in the house?

Blocking some of the vents in your house to lighten the load of the heating system may not work as well as you think. In fact, doing this could be counterproductive.

Your heating system and vents are designed and put in place with the whole house in mind. If you block one vent, the system will work harder and heat the house more so that the warm air can flow into the cold room. So, instead of taking the pressure off the heating system, it could increase it.

For your heating and cooling system to heat the rooms in the house properly, all of the vents must be open.


Is your ceiling vent constantly spewing old cold air? Sitting next to a drafty vent all day could be rather uncomfortable. So much so that you’re no doubt keen to get the vent blocked immediately. That’s why the steps in this article have pointed out how you can close the vent using a switch, dial, or insulation.

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Have a great day!