Conquering Drafts: A Comprehensive Guide to Covering Air Vents in Your Wall

Air vents in the wall, while essential for ventilation and HVAC systems, can sometimes become a source of unwanted drafts, energy loss, and even noise pollution. If you have a vent that’s no longer in use, or if you’re looking to temporarily seal one off during remodeling or for specific seasons, knowing how to cover it effectively is crucial. This detailed guide provides step-by-step instructions and a variety of methods to help you cover those wall vents successfully, addressing different scenarios and preferences.

Why Cover a Wall Air Vent?

Before we dive into the “how,” let’s understand the “why.” There are several valid reasons why you might want to cover a wall air vent:

• Unused Vents: If a room’s heating or cooling needs have changed, or you’ve reconfigured your HVAC system, certain vents might be rendered obsolete. Leaving them open can lead to wasted energy and unnecessary drafts.
• Drafts: Even if the vent is still connected to the system, it might leak cold air in the winter or hot air in the summer, creating uncomfortable drafts and increasing your energy bills.
• Renovations: During remodeling projects, covering vents can help prevent dust and debris from entering the ductwork.
• Noise Reduction: Wall vents can sometimes act as conduits for noise from other rooms or the outside. Sealing them off can help to create a quieter environment.
• Temporary Closure: You might want to close off vents in certain rooms for specific periods of the year, like during the summer in areas that are rarely used.

Important Considerations Before You Start

Before you begin covering any vents, consider these crucial points:

• HVAC Functionality: Ensure that the vent you’re covering is truly unnecessary. Sealing off crucial vents can impact your HVAC system’s performance, causing uneven heating or cooling and potentially damaging your equipment. If you are unsure, consult a HVAC professional.
• Building Codes: Some areas may have specific building codes or regulations regarding the sealing of air vents. Check with your local building authority to ensure compliance.
• Permanence: Decide if you need a temporary or a permanent solution. Some methods are easier to reverse than others.
• Vent Type: Identify the type of vent you have (supply vent, return vent, etc.) as different types might require a slightly different approach. If you are unsure consult a professional.
• Material Compatibility: Consider the type of wall and existing vent materials when selecting your covering method. Compatibility with paints, adhesives, and other sealants is important.
• Safety: Never cover or seal gas vents. These vents are essential for safety and their proper functioning is critical.

Methods for Covering Wall Air Vents

Here are several methods you can use to cover your wall air vents, ranging from simple temporary fixes to more permanent solutions:

1. Temporary Sealing with Magnetic Covers

Best for: Temporary closures, easy removal, vents that are not completely flush with the wall surface.

Materials Needed:

• Magnetic vent covers (available in various sizes and designs)
• Measuring tape
• Optional: Cleaning supplies (for cleaning the vent before applying the cover)

Instructions:

1. Measure the Vent: Use a measuring tape to determine the dimensions of the vent opening (length and width). Add a bit extra to ensure the magnetic cover completely covers the vent opening.
2. Clean the Vent: Before applying the magnetic cover, clean the vent surface with a damp cloth and all-purpose cleaner. This helps the magnet make better contact and ensures proper seal. Let it dry completely.
3. Attach the Magnetic Cover: Carefully align the magnetic cover over the vent opening. The magnets should securely hold it in place. Make sure the entire vent opening is sealed.
4. Check for Gaps: Run your hand along the edges to make sure there are no gaps. If gaps persist, you might need a larger or differently shaped cover, or use an additional sealant for a tighter fit.

Pros:

• Easy to install and remove.
• Requires no special tools.
• Reusable.
• Available in different sizes and designs.

Cons:

• May not provide a complete seal for all vents.
• May not be suitable for very uneven surfaces.
• Not ideal for permanent solutions.

2. Using Painter’s Tape and Cardboard

Best for: Temporary closures, quick fixes, vents with flat surfaces.

Materials Needed:

• Painter’s tape
• Cardboard (a piece slightly larger than the vent opening)
• Measuring tape
• Scissors or utility knife
• Optional: Cleaning supplies (for cleaning the vent surface before applying the tape)

Instructions:

1. Measure the Vent: Measure the length and width of the vent opening using a measuring tape.
2. Cut the Cardboard: Cut a piece of cardboard that is slightly larger than the vent opening. Adding a 1-2 inch margin is a good approach to ensure that the cardboard will fully cover the vent and have enough overlap to adhere it to the wall.
3. Clean the Vent Surface: If needed, wipe the surface around the vent opening with a damp cloth to remove dust and dirt. Allow the area to dry completely.
4. Position the Cardboard: Carefully position the cut cardboard piece over the vent opening. Ensure it’s centered to cover the entire opening effectively.
5. Secure with Painter’s Tape: Use painter’s tape to secure the cardboard to the wall around the edges. Press the tape firmly against the wall to ensure a good seal. Be thorough and ensure that all sides are well secured.
6. Check the Seal: Run your finger along the tape edges to ensure there are no gaps. Reinforce with more tape if needed.

Pros:

• Inexpensive and readily available materials.
• Easy to install and remove.
• Good for temporary solutions.

Cons:

• Not very aesthetically pleasing.
• May not provide a completely airtight seal.
• Not durable for long-term use.

3. Sealing with Foil Tape

Best for: A tighter seal, covering less visible vents, temporary or short term solution, vents that are mostly flat.

Materials Needed:

• Foil tape (also known as aluminum tape or HVAC tape)
• Measuring tape
• Cleaning supplies (for cleaning the vent before applying the tape)
• Scissors or a utility knife

Instructions:

1. Clean the Vent Surface: Use a damp cloth to clean the vent and the surrounding wall area. Ensure it is fully dry before proceeding.
2. Measure and Cut the Tape: Measure the dimensions of the vent opening, adding extra length to cover all edges. Cut strips of foil tape according to these measurements. It is generally easier to work with strips than trying to manipulate one large piece.
3. Apply the Tape: Carefully apply the foil tape to the vent opening. Start by covering the edges and then move towards the center. Make sure each strip overlaps slightly to create a seal. Use the flat edge of a rigid object or your finger to press down firmly on the tape to smooth out any wrinkles and improve adhesion.
4. Ensure Complete Seal: Check for any gaps and bubbles around the edges. Press down firmly to seal these. Add additional strips of tape as needed to fully seal off the vent. The goal is to create an airtight closure.

Pros:

• Durable and provides a good seal.
• Relatively inexpensive.
• Suitable for less visible vents.
• Effective in preventing drafts.

Cons:

• Can be more visible than other methods, since it is metallic.
• May leave sticky residue upon removal.
• Requires more precision to apply evenly.

4. Using a Foam Board and Caulk

Best for: A more permanent and durable seal, vents that have a more consistent and flat surface around them.

Materials Needed:

• Foam board (rigid insulation board, cut to size)
• Measuring tape
• Utility knife or saw
• Caulk (sealant compatible with both wall and foam board)
• Caulk gun
• Spatula or putty knife
• Cleaning supplies (for cleaning the vent and area around it)
• Optional: Primer and paint to match wall if foam board has a different color

Instructions:

1. Measure the Vent: Measure the vent opening and add approximately 1 to 2 inches on all sides to ensure full coverage.
2. Cut the Foam Board: Cut a piece of foam board to the measured size using a utility knife or saw. Ensure the piece you cut covers the entire opening completely and allows for the caulk to adhere to the wall surrounding the vent
3. Clean the Area: Clean the vent and the wall surrounding the vent with a damp cloth and let it dry completely. Ensure there are no dust, or any other dirt and debris on the surfaces.
4. Position the Foam Board: Place the foam board over the vent opening to verify its fit. It should fully cover the vent with a sufficient margin on all sides to allow for the caulk to adhere to the surrounding wall.
5. Apply Caulk: Apply a thick bead of caulk around the perimeter of the vent opening on the wall where the foam board will make contact. Be generous with the caulk to ensure a good seal.
6. Attach the Foam Board: Carefully press the foam board onto the caulk, ensuring that the board is positioned correctly over the vent opening. Press down firmly and hold for a few seconds to ensure it adheres to the wall.
7. Smooth the Caulk: Use a spatula or putty knife to smooth the caulk along the edges of the foam board. This creates a neat seal and eliminates any gaps or bubbles. Remove any excess caulk using a wet rag or sponge.
8. Let it Dry: Allow the caulk to dry completely according to the manufacturer’s instructions. This may take several hours or overnight.
9. Finish (Optional): If desired, apply primer and paint to the foam board to match the color of the surrounding wall for a more seamless look.

Pros:

• Provides a very good airtight seal.
• Durable and long-lasting.
• Can be painted to match the wall.

Cons:

• More permanent than other methods.
• Requires more preparation and materials.
• Can be more difficult to remove.

5. Drywall Patching (Permanent Solution)

Best for: Permanent vent closure, blending it seamlessly into the wall, experienced DIYers, or hire a professional for this.

Materials Needed:

• Drywall patch (same thickness as existing drywall)
• Measuring tape
• Utility knife or drywall saw
• Drywall screws
• Drywall compound (mud)
• Drywall tape
• Putty knife (various sizes)
• Sanding sponge or block
• Primer and paint
• Drill and drill bits
• Stud finder to ensure your patch will be screwed into existing studs
• Cleaning supplies (for cleaning the vent and area around it)

Instructions:

1. Measure the Vent: Measure the vent opening, adding extra space to allow for proper attachment to the existing drywall using screws.
2. Clean the area: Using a wet rag, clean the area surrounding the vent to remove dust and any other debris.
3. Cut the Drywall Patch: Cut the drywall patch to the measured size. You will want to cut it carefully to ensure it has a precise fit.
4. Position the Patch: Place the drywall patch over the vent and position it ensuring it covers the vent completely and overlaps existing drywall by at least an inch on all sides, if possible.
5. Attach the Patch: Use drywall screws to attach the drywall patch to the existing wall. Make sure to screw the patch into studs. You may need to cut or remove part of the old vent material to do so. Use the stud finder to locate the studs. Countersink the screw heads just below the surface of the drywall, but not too far as to break through the drywall paper.
6. Apply Drywall Tape: Apply drywall tape over all the seams between the patch and the existing drywall. Make sure the tape is applied evenly to avoid wrinkles and bubbles.
7. Apply Drywall Compound: Apply a thin layer of drywall compound (mud) over the drywall tape and the entire area of the patch. Use a wide putty knife and feather out the edges, blending with the surrounding wall.
8. Allow to Dry and Sand: Allow the first coat of mud to dry completely according to manufacturer instructions. Sand it smooth with a sanding sponge or block. Apply more thin coats of mud as needed until the patch is perfectly level with the surrounding wall. Remember to let each coat dry completely before sanding and applying the next one.
9. Clean up: Use a damp rag and sponge to clean up any dust that resulted from sanding.
10. Prime and Paint: Once satisfied with the smoothness of the patch, apply primer to the patched area and allow to dry. Then, apply matching paint and allow to dry. If you have texture, you might need to apply texture before painting to ensure a seamless blend with the surrounding wall.

Pros:

• Creates a completely seamless and permanent closure.
• Visually integrates the vent area into the wall.

Cons:

• The most labor-intensive method.
• Requires more skills and tools.
• Very difficult to reverse.
• Time consuming.

Final Thoughts

Covering a wall air vent doesn’t have to be a difficult task. By carefully assessing the purpose of the vent, choosing the right method for your situation, and following the step-by-step instructions provided in this guide, you can effectively seal off unused or problematic vents. Whether you opt for a simple magnetic cover or a more involved drywall patch, remember to prioritize safety, functionality, and the overall aesthetics of your home. Always double-check that you are not covering an active ventilation vent before commencing work. If you have any doubts about your HVAC system or the proper method for your specific situation, consult with a qualified HVAC professional.