Fort Collins (970) 517-3931
Colorado Springs (719) 270-4494

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Infinity From Marvin Specialty Shapes Windows


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Specialty Window Installation in The Fort Collins Area

Whether you are looking to add visual interest to a room or are simply replacing an old window, Infinity Specialty Shapes are a stunning addition to any space. Adding an Infinity Round Top above a standard window or door instantly adds light and style to your home.

Achieve open views and abundant natural light with the Infinity Polygon, available in a variety of styles from stand-alone Picture Windows that span up to 10 feet to geometric combinations that give you design flexibility.

Interested in specialty windows? Get started with a free quote now! Our experts offer skilled specialty window installation and replacement in Loveland, Fort Collins, Greely, and beyond!

Polygon Shapes

Round Top Shapes

More Options For Your Home

Two-Wide Polygon

Three-Wide Polygon

Round Top Assembly

Round Top Assembly


According to HomeAdvisor, 25% of the costs for heating and cooling your home comes from the energy lost through your windows.

Carefully considering which type of window is right for your Fort Collins home could save you thousands of dollars in energy costs, while increasing the resale value of your home.

Also, independent market studies have noted that 65% of service related issues to prematurely failed windows are related to improper installation. This is due to:

  • short cuts during the installation of new or replacement windows
  • low-cost faulty sealants
  • improper flashing methods

Whether you prefer a half round window, full circle window, or another unique window style, Nex-Gen Windows & Doors has the expertise you require. Schedule specialty window installation in Fort Collins, Cheyenne, Lafayette, the surrounding area!

infinity from marvin replacement windows nex-gen windows and doors

What are the best replacement windows for my home?

We’re making it easier for you to buy replacement windows and doors by sharing what to expect during your project. Learn more about how you can find the best window for your home.


1. Expert Consultation

A Nex-Gen windows and doors expert will provide a complete consultation to determine your specific needs — including climate considerations and other factors. They will answer all your questions and provide a detailed, custom project quote based on your specifications.

2. A Perfect Fit

We’ll review your order, measure your openings and verify your installation needs. Your windows will then be built to your exact needs and measurements.

3. Seamless Installation

We’ll remove and dispose of your old windows, and replace them with your custom Infinity windows.

4. Built for Life®

From our Limited Lifetime Warranty to unparalleled customer service, we go above and beyond to ensure your windows provide a lifetime of optimal performance.


At Nex-Gen we’re changing the way Window & Door replacement has been done in the past. Our Expert Staff will provide industry leading solutions for your home improvement needs. The right product for your budget and desired functionality. Our promise is to provide a low pressure, educative consultation while allowing you to be the judge to make the right decision for your homes’s needs.

  • 1

    Let’s Begin

    We start with a phone call to collect information about your home, your replacement needs, and your goals. Every project is unique; we learn as much as we can upfront to ensure a successful remodel experience.

  • 2


    We visit your home to get a first-hand look at the project and to familiarize you with our process. We discuss products and innovative solutions, and provide a transparent cost vs. value analysis and detailed proposal.

  • 3


    Our Elite Window Experts take meticulous measurements to ensure a smooth installation. Accurate window measurements also maximize energy efficiency and protect the aesthetics of your home.

  • 4


    You stay informed with periodic updates via phone, email or text. Scheduling changes are sometimes unavoidable due to the manufacturer’s date changes or inclement weather. We keep you posted in real time.

  • 5


    Our installers come and go with minimal disruption to your routine. No need to leave your home; most installations are completed in 1-2 days. Our crew members receive special training and pass background checks.

  • 6


    Upon completion, the lead installation tech does a walk-through final inspection. He provides operating instructions for your new windows and doors and reviews the warranty information.

  • 7

    Let Us Know

    We ask that you complete a survey as the final step in our process. Collecting feedback about your experience keeps us on our toes. If we didn’t meet your expectations, we want the opportunity to make it right.


Several of the windows are oversized. We are very pleased with our window experience. Ted has come out several times to check on the progress of the windows. I know this was not an easy job, but the windows look terrific. They took out a large patio door and replaced it with a custom bay window. I cannot speak to how they install siding, but I would expect they would install with the same quality service.

Their window installer, Shane was very professional and said he “would not leave until everything is right”. I would recommend Nex-Gen to my colleagues and friends.

Nancy U.

better business bureau accredited business nex-gen windows and doors
infinity from marvin replacement windows nex-gen windows and doors


better business bureau accredited business nex-gen windows and doors
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“Serving Northern Colorado From Fort Collins to Denver, Estes Park to Greeley – We’re here for you.”

Improving your home, Windows, Doors, Siding Installation