Step 1: Determine the size of the insert. Inserts may replace the entire window or just a section.
For a casement, hopper, or awning window (opens out) full window replacement is required. To determine the size of the vent insert, measure the screen.
Screens are often not square, so measure the top and bottom, left and right sides. If the measurements are more than ¼” different, add the two measurements and divide by 2. If the screen has a lip, make sure to measure the outermost edge of the screen.
For a partial window insert for a sliding window, find the height by measuring from inside the top track to the window frame edge on the bottom. It is important not to measure inside the track at the bottom or your piece will be too big to fit in the window. The minimum width is 10 inches for a 4-inch vent and 12 inches for a 6-inch vent.
For a partial window insert for a single or double hung window, find the width by measuring from inside the left track to the window frame edge at the right. It is important not to measure inside the right track or your piece will be too big to fit in the window. The minimum height is 10 inches for a 4-inch vent and 12 inches for a 6-inch vent.
Step 2: Determine the size and shape of the connector. They come in many shapes and sizes. If your order is to be shipped, only 4-inch, 5-inch, and 6-inch circles are available. You can easily replace the manufacturer’s adaptor with a standard 4-inch, 5-inch or 6-inch circular adaptor. If you are picking up from your local store, they can work with you on unique shaped adaptors. The physical adaptor will have to be provided as there are hundreds of different adaptors out there, many of which look very similar.
For circle adaptors, determine the diameter of the hose for the cutout. Measure outer edge to outer edge of the hose.
Step 3: The cutout will be placed 3” in and 3” up (measured from the edge of the cutout) to maintain structural integrity. If you require a different placement, please make a note in Additional Instructions when completing your order.
Step 4: Submit. Your order will be reviewed and you will be contacted for payment. All window vents are made to order and will take at least 2 days to complete. Up to 7 days during the Summer months.
How to Measure Your Window Vent Dimensions
Step 1: Determine the size of the insert. Inserts may replace the entire window or just a section.
For a casement, hopper, or awning window (opens out) full window replacement is required. To determine the size of the vent insert, measure the screen.
Screens are often not square, so measure the top and bottom, left and right sides. If the measurements are more than ¼” different, add the two measurements and divide by 2. If the screen has a lip, make sure to measure the outermost edge of the screen.
For a partial window insert for a sliding window, find the height by measuring from inside the top track to the window frame edge on the bottom. It is important not to measure inside the track at the bottom or your piece will be too big to fit in the window. The minimum width is 10 inches for a 4-inch vent and 12 inches for a 6-inch vent.
For a partial window insert for a single or double hung window, find the width by measuring from inside the left track to the window frame edge at the right. It is important not to measure inside the right track or your piece will be too big to fit in the window. The minimum height is 10 inches for a 4-inch vent and 12 inches for a 6-inch vent.
Step 2: Determine the size and shape of the connector. They come in many shapes and sizes. If your order is to be shipped, only 4-inch, 5-inch, and 6-inch circles are available. You can easily replace the manufacturer’s adaptor with a standard 4-inch, 5-inch or 6-inch circular adaptor. If you are picking up from your local store, they can work with you on unique shaped adaptors. The physical adaptor will have to be provided as there are hundreds of different adaptors out there, many of which look very similar.
For circle adaptors, determine the diameter of the hose for the cutout. Measure outer edge to outer edge of the hose.
Step 3: The cutout will be placed 3” in and 3” up (measured from the edge of the cutout) to maintain structural integrity. If you require a different placement, please make a note in Additional Instructions when completing your order.
Step 4: Submit. Your order will be reviewed and you will be contacted for payment. All window vents are made to order and will take at least 2 days to complete. Up to 7 days during the Summer months.
Adapt your AC vent
to any size window
without cardboard!
Custom Portable AC Window Exhaust Adapter for Sliding, Casement, and Swing-Out Windows
Struggling to vent your portable air conditioner with a window that doesn’t fit the standard kit? Our Custom AC Window Vent Insert offers a fast, effective solution—whether you have casement windows, sliding windows, or vertical-hung windows. Designed to help you connect your AC hose securely and remove hot exhaust from your home or business, this insert dramatically improves the performance and energy efficiency of your portable air conditioner.
Each insert is custom-cut to your window’s exact size and made from durable, weather-resistant polycarbonate in your choice of finish: Crystal-Clear, Transparent Smokey Gray, or Solid White for added privacy while retaining some light transmission.
Clear Polycarbonate
Smoke Grey
White
✅ Solve Common Compatibility Issues with Custom Fit
Portable air conditioner exhaust kits often don’t work with crank-out (casement) windows or unusual sliding windows—but our made-to-order AC vent insert fills the gap. Simply input your window dimensions and vent hole preference into our online calculator to receive an instant quote.
You can also select the hole side, request a second hole for dual-hose models, and choose your color and thickness—all online.
Thickness recommendations by sheet square footage:
Window Size in Square Feet (L x W)
Recommended Thickness of Plastic
Less than 5 Sq. Ft.
1/8"
6-15 Sq. Ft.
3/16"
15-32 Sq. Ft. or greater
1/4"
Key Features
Made from Tough Polycarbonate: Shatter-resistant and built to last, our non-yellowing polycarbonate plastic is ideal for indoor and outdoor use.
Precision Custom Sizing: Enter your window dimensions to get a perfect-fit insert that spans your full window or partial opening—ideal for awkward sizes and styles like casement or swing-out windows.
Tailored Vent Openings: Choose standard 4", 5", or 6" diameter hose openings—or request a custom size to fit your AC hose exhaust shape by contacting us. Dual-hose setups can include a second vent hole.
Simple DIY Installation: Use double sided stick pads, Velcro®, or edge trim to install and seal the insert without tools. No permanent modifications required.
Weather-Resistant Performance: Designed to withstand seasonal temperature changes and moisture without warping or cracking. For complete weather proofing, use foam or rubber weather stripping to fill in any gaps between the frame.
Three Stylish Color Options: Select from crystal clear, transparent smoke gray, or non-transparent white to match your window frame and privacy needs.
FAQs
What window sizes do you support?
We can fabricate inserts up to 48" x 96", big enough for most large or full-size windows.
Is this compatible with all portable AC models?
Yes—our insert is designed to work with nearly all brands. Just measure your hose diameter and we’ll custom-cut the vent hole to match.
Will it work with crank windows (casement windows)?
Absolutely. Unlike standard kits, our insert can be sized to fit the entire window opening and accommodate the outward swing of casement-style frames.
What tools are required for installation?
No tools are needed. Most customers install their insert using removable adhesive tape or Velcro strips. We also recommend edge trim to help seal gaps.
Can I request a second vent hole?
Yes. For dual-hose AC units or systems using intake/exhaust airflow, just select the second hole option when configuring your kit.
Is it reusable? Yes, the insert can be easily removed and reused from season to season.
Will this help my AC unit run more efficiently?
Yes. A tight seal keeps hot air out and cool air in, reducing load on your portable AC and improving energy efficiency.
What colors are available?
Choose between Clear, White, or Transparent Solar Gray polycarbonate for your ideal balance of light, privacy, and style. Contact Us for additional colors and materials.
Why Choose TAP Plastics?
With over 70 years of plastic fabrication expertise, TAP Plastics delivers quality you can trust. Our custom AC window vent inserts are cut to your exact specifications and made from premium materials you won’t find in off-the-shelf kits. You can order online for direct shipping or order in-store at one of our convenient retail locations.
Questions? Call us at 888-827-7330 or email info@tapplastics.com—our team is here to help.
