Scorching summer heat or freezing winter temperatures – wherever you live, whatever the climate, Infinity from Marvin replacement windows are outstanding performers.

Infinity Windows by NEXT Door and Window

Ultrex Fiberglass is 8X stronger than vinyl!

Boy on Fiberglass Boy On Vinyl
Don’t worry. Ultrex can take whatever Mother Nature dishes out because it’s pultruded fiberglass, a material used in products where strength and durability are required. In fact, it’s such a solid, long-lasting material that it’s trusted for use in bridge construction.

Peace of mind. With a view.

Viewed thru Vinyl Viewed thru Infinity
Take a second look at Infinity’s tough, narrow frame made of Ultrex fiberglass. The Ultrex advantage allows for more glass area than other replacement windows giving you more daylight and better views. Infinity replacement windows are made from Ultrex fiberglass, inside and out. Marvin has nearly two decades of experience creating window and door products made with this strong fiberglass material. The reason we chose it for Infinity replacement windows is simple: fiberglass is superior to other window materials in virtually every category.

Low Maintenance – Streaks and Cracks

Over time, vinyl will show its age. Spots, streaks and cracks can appear, and once they do, there isn’t much you can do to help. Ultrex fiberglass stands up to the elements and keeps windows looking great for years.

Standing up under pressure

Scorching summer heat or freezing winter temperatures – wherever you live, whatever the climate, Infinity from Marvin replacement windows are outstanding performers. Our replacement window line meets or exceeds industry ratings for air, water and structural performance. Infinity replacement windows are designed to a performance rating of DP30, depending on size, which is a measure of the amount of pressure a window or door is designed to withstand when closed and locked. This means Infinity replacement windows remain strong (standing up to 45 pounds of pressure per square foot, which is equivalent to the pressure created by 132 mph winds) and watertight (withstanding water penetration when exposed to the equivalent of 8” of rain per hour driven by 42 mph winds).

Ultrex fiberglass stability

Infinity Stability
Ultrex is an ideal material for windows not only for its amazing strength and ability to repel the elements, but also for its low thermal expansion rate. Cold, heat and time can be tough on some window materials. Vinyl, for instance, can distort in extreme heat due to its high thermal expansion rate (see chart below). Ultrex resists distortion even at temperatures up to 350 degrees F. Rapid temperature change doesn’t faze it either. When the mercury climbed from -30 degrees F to 70 degrees F, a 6’ stile changed less than 1/32” in length!

A “STAR” Performer

Energy Star LogoThe ENERGY STAR rating from the U.S. Department of Energy and the U.S. Environmental Protection Agency is only granted to products that are designed to reduce energy usage to mandated levels. Infinity from Marvin exceeds the performance requirements and qualifies for the ENERGY STAR rating in all U.S. climate regions.

Energy Efficiency

As proof, Infinity products have one of the highest performance ratings from the National Fenestration Rating Council (NFRC), the organization that defines energy performance ratings for the window and door industry.

Built Green

Green Logo
Ultrex fiberglass is made of partially recycled material, and the main ingredient of Ultrex fiberglass is silica sand, an abundant natural resource. The glass in our products contains 15% – 33% recycled content. Additionally, Ultrex requires 39% less energy to produce than vinyl.

Infinity Limited Lifetime Warranty

Infinity windows are covered by a Limited Lifetime Warranty protects owner-occupants of single family, detached homes who have purchased their windows and doors through an authorized Infinity retailer on or after January 19th, 2010 are eligible for the Limited Lifetime Warranty.

Infinity Sweepstakes


Infinity Bay



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Infinity Bow



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Infinity Double Hung



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Infinity Glider



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Infinity Options



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