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Preseason orders will begin to ship April 1st
Preseason orders will begin to ship April 1st

Custom Portable AC Vent Kit for Awning & Basement Windows

Custom Portable AC Vent Kit for Awning & Basement Windows

Installing a portable AC in an awning or basement window usually turns into a workaround. Most portable AC window kits are designed for sliding windows, leaving awning windows with gaps, loose seals, and hot air leaking back inside.

This custom portable AC awning window vent kit solves that problem.

Each portable AC window insert for awning windows is CNC-cut from durable ¼" clear acrylic and made to your exact window measurements, creating a tight seal around the exhaust hose while still allowing your window to open normally.

The quick-attach vent system locks securely into the panel for easy hose connection, and the non-permanent installation kit lets you install the awning window AC vent kit in about 5–10 minutes without drilling or damaging your window frame.

Build Your Custom Insert
Shipping

For current production lead times, please check the red banner at the top of the website.

 All U.S. orders ship free via UPS Ground and typically arrive within 3–5 business days once shipped.

Need it faster? Expedited shipping options are available at checkout:

2nd Day Air – $45
Overnight – $75

Shipping to Canada is $15 CAD via UPS Ground. Please note that import duties and taxes may be charged upon delivery.

Specifications

• Panels are made from durable ¼″ clear acrylic.
• Corners are slightly rounded (⅛″ radius) for safety.
• Panels are cut 1/16″ smaller than the provided measurements to ensure a proper fit.

Most window frames are not perfectly square, and this small adjustment allows the insert to seat correctly in the opening.

 This approach has been refined through thousands of installations to provide the most reliable fit.

Awning Windows Weren’t Designed for Portable AC Kits

Most portable AC vent kits are designed for sliding or double-hung windows. When you try to use them with an awning or basement window, they rarely seal properly. Instead of a clean vent, you end up trying to patch the opening with makeshift fixes.

Homeowners usually end up dealing with problems like:

  • Cardboard or foam stuffed around the hose opening

  • Generic panels that never fit the window frame correctly

  • Hot air leaking back into the room
Build Your Perfect Awning Insert
Trusted by thousands of homeowners who needed a real awning window vent solution.

Built for Your Window. Built to Last.

Every detail of our custom acrylic window vent panel is engineered to give you a flawless, lasting solution, not another workaround.
CNC Machined Precision

CNC Machined Precision

If it doesn't fit, we remake it. Even if the measurement mistake was yours. No risk.

Crystal Clear Acrylic

Crystal Clear Acrylic

Durable ¼" clear acrylic. Strong, stable, and designed to preserve natural light.

5-10 Minute Install

5-10 Minute Install

No permanent modifications. Secure fit using a simple, non-invasive install kit.

Manufactured in USA

Manufactured in USA

Precision CNC-cut in-house. Built to order for your exact window dimensions.

Weather-Resistant

Weather-Resistant

Designed to handle heat and humidity. Maintains structure and seal through the season.

Free Shipping

Free Shipping

Free U.S. shipping. Delivered in 5–7 days. Fast turnaround when you need cooling now.

Build Your Perfect Awning Insert
Trusted by thousands of homeowners who needed a real sliding window vent solution.

Airtight Seal. Maximum Cooling Efficiency.

Stop losing cold air through gaps and improvised seals. This portable AC window vent panel creates an airtight barrier around your exhaust hose, keeping hot air outside where it belongs so your AC cools efficiently instead of fighting air leaks.
Build Your Perfect Awning Insert
Trusted by thousands of homeowners who needed a real sliding window vent solution.

Keep Your View. Keep Your Home Cool.

Vent your portable AC through awning windows without blocking natural light or covering the glass. The clear acrylic insert creates a clean exhaust opening so hot air vents outside while your window continues to open, close, and function normally – keeping the room comfortable without sacrificing the view.
Build Your Perfect Awning Insert
Trusted by thousands of homeowners who needed a real sliding window vent solution.

Perfect Fit Guarantee

If your window insert doesn’t fit perfectly, we’ll remake it – free of charge. 



Even if the measuring mistake was yours.

Email us at info@martinsonmanufacturing.com and tell us what needs adjusting. “Make the width ½ inch shorter.” “Tighten the height.” Whatever it takes. We’ll cut a new one and ship it the next business day. 

We don’t leave customers stuck with something that doesn’t work.

Step-by-step measuring video guides you
Universal hose design fits every AC unit
Every order reviewed before fabrication
If it doesn’t fit, we remake it for free
Build Your Perfect Awning Insert
Trusted by thousands of homeowners who needed a real sliding window vent solution.

Stop Allowing the Heat to Completely Take Over Your Home

You feel it every evening – the AC is running, the hose is humming, yet the room still feels heavy. Warm air seeps back in, the temperature never quite stabilizes, and you’re left adjusting settings that don’t fix the real issue.

That’s not an AC problem. It’s a window problem.



Generic kits are built for sliding windows. When you force them into casement frames, they leak. The system works harder, energy use climbs, and comfort never fully settles.



This insert corrects the problem at the source – the window – so your AC can cool the room the way it was meant to.



Cooler air. Steadier temperatures. Less frustration.

Build Your Perfect Awning Insert
Trusted by thousands of homeowners who needed a real sliding window vent solution.

Frequently Asked Questions

If your insert doesn’t fit your window perfectly, we’ll remake it for you free of charge. Even if the measurement mistake was yours. Just email us and tell us what needs adjusting and we’ll cut a replacement panel.

Yes. These inserts are designed specifically for awning, hopper, and basement-style windows. Each panel is custom cut to your measurements to create a proper seal around the AC hose opening.

Yes. The insert is designed to work with standard portable AC exhaust hoses and vent systems. The quick-attach vent creates a secure connection so hot air exhausts outside instead of leaking back into the room.

Installation is simple and non-permanent. The insert fits into the window opening and secures with the included installation kit. Most customers install it in about 5–10 minutes without drilling or modifying the window frame.

Orders are custom cut after you submit your measurements. Most inserts arrive within about 5–7 days, and free shipping is included for U.S. orders.

Awning Windows Done Right

Portable AC units fail with the wrong window setup. This awning window AC vent kit fixes that.
★★★★★ 4.9/5 | 1,904
Martinson Manufacturing
Precision window inserts fornon-standard openings.
Call Today 262-340-1418
Build Perfect Awning Insert
Trusted by thousands of homeowners who needed a real sliding window vent solution.

Martinson Manufacturing designs and produces precision window inserts for portable air conditioners. Built for non-standard windows, each insert is made to exact dimensions and engineered to fit cleanly, install easily, and perform reliably in real homes.

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Our Promise

Every insert we build is
designed to fit your window exactly, install cleanly, and work the way it should. If it doesn’t fit right, we’ll remake it. No workarounds, no damage, no guesswork, just a solution that performs reliably in your home. Every time.

Contact

Martinson Manufacturing
705 Schoenhaar Dr #101West Bend, WI 53090
262-340-1418
info@martinsonmanufacturing.com
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