infinity® windows
The Infinity Fiberglass Advantage
Infinity's patented Ultrex® fiberglass delivers lasting performance:
- Expands 87% less than vinyl - resists expanding and contracting in any climate
- 8 times stronger than vinyl - protects the integrity of your home
- Resistant to leaks, seal failures and stress cracks - all things that can affect energy efficiency
For more information on the Ultrex® fiberglass, click here.


Durability
Color
Architecture
Color
Durable
Easy
Window Features
Tough Durability
Ultrex® fiberglass exterior finish is virtually impermeable and protects your windows from the effects of wind, weather, and time.
Exterior Color Options
Bring out the beauty in your home with Infinity's proprietary acrylic finish and color options. Three times thicker than other windows, the finish is virtually maintenance-free. No more sanding, scraping or painting required.
Click here to see all exterior color options.Aesthetically Pleasing
Because of Ultrex’s incredible strength, Infinity's fiberglass windows have narrower frames — so you get more incredible views for your money. Infinity windows also capture the beautiful details and profiles of wood - without the maintenance.
Interior Color Options
Bring out the beauty in your home with Infinity's proprietary acrylic finish and color options. Three times thicker than other windows, the finish is virtually maintenance-free. No more sanding, scraping or painting required.
Click here to see all interior color options.Low Thermal Expansion
This means Infinity windows have a stronger seal that resists sticking, swelling, and warping providing easy operation for the life of the window.
Easy Maintenance
Easy to maintain with Tilt-In sashes for easy cleaning
Explore by Window Type
Select an option to view more information about its features and details.
Why We Only Offer Infinity From Marvin Fiberglass Windows
Compare Infinity
Weather Tightness
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Ultrex® fiberglass has the lowest thermal expansion rate, which keeps the window weathertight, reducing the risk of seal failures and air leakage.
Durabilty
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While many windows can distort in extreme heat or crack in fluctuating temperatures, Infinity's Ultrex fiberglass windows hold true.
Appearance
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Drawing on the decades of experience from Marvin Windows and Doors, Infinity products incorporate the details of traditional wood windows without the maintenance.
Low Maintenance
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The patented acrylic finish and low expansion rate of Ultrex keep Infinity windows looking new and virtually maintenance free.
Maximum View
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The superior strength of Ultrex fiberglass allows for a truly narrower profile than both vinyl and Fibrex® allowing more glass area, giving you more daylight and better views.
Color Choices & Performance
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Ultrex's patented, mechanically bonded inline acrylic finish is up to 3x thicker than competitive finishes, providing superior resistance to discoloring, scratching, and denting.
Reputable Manufacturer
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Marvin Windows and Doors is family-owned with a legacy of innovation and uncompromising performance. We use the finest materials to create exceptional products, backed by first rate service.
Lifetime Warranty
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With Infinity's Limited Lifetime Warranty you'll have piece of mind.
Infinity's (Ultrex®) Fiberglass
Best
Best
Best
Best
Best
Best
Yes
Yes
Vinyl/Wood Composites (Fibrex®)
Better
Better
Better
Better
Better
Better
Yes
No
Vinyl
Good
Good
Good
Good
Good
Good
Varies
No
Premium Quality
Infinity products are designed to replicate the look of traditional wood windows and doors while providing modern features and low-maintenance performance. Made Ultrex®, Infinity's tough, energy-efficient windows and doors are customization to meet the needs of any replacement project.