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How to Close/Seal Garage Vents Permanently


Wall vents must be sealed on either side. This can be done with plywood, screws, and caulk. Ceiling vents can be sealed in the same way, but drywall may be better than plywood. Soffit vents can be replaced with non-vented boards. Or plywood, insulation, or drywall can be installed over the soffit vents.

Whether you are looking to install a new ventilation system in your garage or you would simply like to seal the vents because they are no longer in use, sealing and closing the vents in your garage is possible and may be easier than you think.

It is important to evaluate the pros of ventilating your garage. If you feel that your garage ventilation is still not necessary, though, the processes of sealing and closing wall, ceiling, and soffit vents are detailed below, including solutions that involve leaving the vents as they are.

Assess Ventilation Before Closing

Unless your garage contains hydrogen-generating appliances and/or refueling systems, your garage, since it is an uninhabitable place, does not need ventilation

Ceiling insulation, ventilation system air ducts, fire extinguishing system pipes, electric cable channels under the ceiling of the Parking lot on the open ground floor of the building
Garage vent

That doesn’t mean that it is a waste of time and money to ventilate your garage, though. Nor does it mean that the previous homeowners installed them unnecessarily.

Ventilating your garage can make the air within it more comfortable and safe while you are working in there with the door closed. A ventilated garage can also keep your home safe from carbon monoxide and other dangerous substances, keep your garage’s flooring safe, and can save you money on energy bills.

Take these pros of ventilating your garage into consideration when you are deliberating over whether or not you should close or seal your garage vents permanently. 

If you would still like to keep your garage ventilated but would like to do it in an alternative way, then it might be a wise choice to close or seal these garage vents in order to install a new system. The old vents may hinder the functioning of the new system if not taken into consideration.

Permanently Closing/Sealing Wall Vents

The most simple process is to remove the vent cover and then cover the hole in the wall. The goal is that someone would not be able to tell that there was ever a vent there. This would not involve removing the vents.

For this procedure, you will need:

  1. Take off the cover of the vent. This may require a screwdriver.
  2. Measure the vent opening. These measurements are used to cut plywood to length so that it can cover the whole opening. It must be flush with the edge of the wall.
  3. Once the plywood is cut, use the screws to secure it to the vent opening. The screws should be located where the screw holes were on the vent cover.
  4. Create an airtight seal using duct tape or caulk.
  5. Make this patch of the wall look like the rest of the room using plaster or filler and paint or wallpaper.

With a wall vent, this will have to be done on both sides of the wall, sealing the internal and external vents.

Leaving the Vent Cover On 

If you don’t want to go through the effort of making it look like the vent was never there, you can screw the vent cover back on over the plywood. I would recommend another layer of caulk around this since you aren’t planning on opening it up again.

Permanently Closing/Sealing Ceiling Vents 

The process for permanently closing or sealing ceiling vents is very similar to the process of sealing wall vents. In fact, the same process can be used on a ceiling vent; it would just be a bit more complex since the ceiling is harder to reach. 

Close up horizontal photo of female hand giving thumbs up after cleaning and installing bathroom fan vent cover from ceiling

Instead of plywood, I suggest you try another, more energy-efficient material to work with: drywall. You can also use this to seal wall vents.

Just like in the above process, you need to unscrew your vent cover, remove it, and then measure its dimensions. 

You will then cut the drywall to fit this hole and then screw it into where the holes of the vent cover used to be. 

Then, in order for this patch of the ceiling to match the rest of the ceiling, you can apply texture and paint.

Just like the previous process, the goal here is that someone would not be able to tell that there was ever a vent on your ceiling. 

Texturing and painting might be unnecessary if your garage isn’t as finished as a room in your home (which applies to most garages).

Leaving the Vent Cover On 

As with the wall vents, if you don’t want to make the ceiling look like there was no vent installed, you can screw the vent cover back on.

An alternative solution, and one that is even cheaper than the previous ones (although I would recommend this more as a temporary fix), is to use cardboard as the barrier between the ducts and the vent cover.

This may not look very attractive, but as this is a garage, aesthetics aren’t as important. 

For this process, you must remove the vent cover, install a piece of cardboard that fits inside of the duct, and then use polyurethane tape to secure the cardboard in place. You would then put the vent cover back on.

Permanently Closing/Sealing Soffit Vents

The best way to close or seal soffit vents would be to replace the ventilated soffit boards with solid ones that are not used for ventilation.

This process requires:

  1. When your ladder is positioned and your helper is available to spot you, you need to unmount or unlock both edges of each panel from the retaining channel.
  2. The zip tool is then used to free each panel from its retaining channel (see the first video below).
  3. The soffit must then be moved so that the opposite edge can be unlocked.
  4. The soffit is then free and can be pushed forwards and removed. This must be repeated with each vented soffit panel on your garage. 
  5. Following the removal of the ventilated soffit boards, the new solid soffit must be installed (see the second video below). This can be installed with a hammer and galvanized nails.

Leaving the Vented Soffit in 

If you would like to avoid the project of taking off yards and yards of soffit and then installing an entirely new soffit, you can leave the ventilated soffit and install insulation, plywood, or drywall over it as a second outer layer.

Sources

https://www.ehow.com/how_7510419_seal-air-vents.html

https://theinfinitekitchen.com/recipe/how-do-you-seal-a-wall-vent/

https://www.hunker.com/12275664/easy-way-to-seal-off-old-ceiling-vents-that-dont-close-tightly

https://youtu.be/MZypaC8PsT4

https://youtu.be/gnuSHXFtNmo

https://www.energystar.gov/campaign/seal_insulate/do_it_yourself_guide/about_attic_ventilation

https://www.whatisvinyl.com/how-to-remove-vinyl-soffit/#:~:text=To%20remove%20vinyl%20soffit%20panels%2C%20you%20will%20need%20to%20unmount,panel%20from%20the%20retaining%20channel.

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