Infinity from Marvin Fiberglass Windows

Vinyl vs. Fiberglass Windows

Infinity from Marvin fiberglass windows and doors are built with Ultrex® fiberglass making Infinity windows stronger than vinyl windows and requiring less maintenance than wood windows.

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Materials Matter

Ultrex fiberglass outperforms vinyl and wood

We created Ultrex with one goal in mind: develop the most durable window material in the industry. It’s not only 8 times stronger than vinyl — it resists expanding and contracting in any climate. So you get a tight, snug fit that will last.

Ultrex vs. Vinyl Windows

Vinyl can warp and shift under everyday conditions — potentially making vinyl windows difficult to open and close and affecting their all-around performance. Ultrex resists sticking, swelling and warping so Infinity windows and doors will continue to easily open and close.

Ultrex vs. Wood Windows

Wood windows offer classic beauty that, depending on the environment, can require maintenance and care. Infinity windows capture the beautiful details and profiles of wood - without the maintenance.

Infinity windows offer enduring style

Fade-Resistant Finish
More View for Your Money
EverWood Beauty and Texture
Exterior of house with Ultrex fiberglass windows

Want long-term color retention? Ultrex uses an acrylic finish that is fade-resistant and virtually maintenance-free.

With a finish that's 3 times thicker than competitive options, Ultrex resists chipping, denting or peeling.

Because Ultrex is so strong, we actually use less of it in Infinity window frames. That means you get more daylight coming through your window, without bulky materials obstructing your view.

EverWood®, our breakthrough engineered wood grain interior finish, offers natural looks and textures - plus the durability you demand. It looks, feels, paints and stains like wood but is completely low maintenance.

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“From the very first visit by the sales person through installation, this was a very well organized and painless experience. The quality of the windows is excellent in all respects.”

Dan C. — Dallas, TX

“We replaced our 30 leaking windows with Infinity Windows seven years ago. They have been wonderful, no leaks, easy to operate and clean. We could not be happier. Now I need to replace four French doors. Needless to say, I am looking again into Infinity doors.”

Brigitte P. — Sutton, MA

“The Infinity product we purchased is very high quality. And we are glad we chose to upgrade to a better quality window. It will increase our home value.”

Nancy B. — Pittsburgh, PA

“We are extremely pleased with our new windows. We had eight windows and one patio door replaced. The stained EverWood matched our oak trim nicely. Windows seal well and are easy to operate. Workmanship was excellent. Attention to detail was evident. Job well done!”

Joe + Jean R. — Rochester, MN

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Bigger views with fiberglass windows

Because of Ultrex’s incredible strength, we can build narrower frames — so you get more incredible views for your money. But that’s just one example of where Ultrex fiberglass truly exceeds expectations.

Ultrex fiberglass window view


Specifically designed to resist warping and weathering in any conditions for long-lasting durability.

Vinyl view


Can shift up to 1/4” under everyday conditions— potentially compromising your home’s integrity.

Window material strength

Compared to other materials, Ultrex is the strongest window framing material in the replacement industry. That means Ultrex resists bending and flexing - that's confidence Fibrex® and vinyl simply can't match.

Ultrex is 8x stronger than vinyl

Ultrex offers superior bend and flex resistance to protect the integrity of your home.

Wood/Vinyl Composite Fibrex®

Resists window leaks

Ultrex expands at virtually the same rate as glass, so our windows stay tight and true. This makes Infinity windows resistant to leaks, seal failures and stress cracks that can compromise energy efficiency and long-term performance.

Ultrex is stable like the glass in your window

Vinyl expands at a much higher rate than glass which may compromise your window’s performance.

Wood/Vinyl Composite Fibrex®
Fibrex® is a registered trademark of Andersen Corporation.

Moving our legacy forward

Marvin is proud to have provided customers across the U.S. with quality windows and doors for over 100 years. But we’re not content to rest upon our heritage. We created Infinity from Marvin to provide homeowners with a new way to shop for replacement windows — centered on providing ease, confidence and a quality experience every step of the way.

Discover what Infinity can do for you

Replace your windows with confidence

Schedule a consultation with your local Infinity partner to learn how Infinity can help you bring new life to your home.

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