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Ultrex Fiberglass Windows

Ultrex® Fiberglass Replacement Windows


Created for strength and beauty

Our patented process starts with strong cables of glass that are saturated with specially compounded resins that are pulled through a heated die and cut with diamond-edge blades. Below are the steps Ultrex® goes through from forming and curing all the way to the cutting stage. All of these steps create a remarkably durable material that outlasts and outperforms other window materials.


Advantages of Ultrex® Fiberglass

  • Low maintenance
  • Base material is silica sand — an abundant natural resource
  • Intricate profiles replicate the look of traditional wood windows
  • Low expansion provides easy operation for the life of the window
  • Strength keeps windows square and true
  • Narrow profiles allow for more visible glass area and expanded views
  • Long-term stability reduces the risk of seal failures and air leakage through the window
  • Patented, mechanically bonded inline acrylic finish is up to 3x thicker than competitive finishes, providing superior resistance to discoloring, scratching, and denting
  • Ultrex® fiberglass is 8x stronger than vinyl and one square inch can support 34,000 pounds!*
  • Fiberglass windows have a 38% longer useful life expectancy than vinyl**
  • Infinity windows with LoĒ glazing can reduce your heating and cooling bills by up to 30%***

* Stiffness of the material to perform as designed. This stiffness is the flexural modulus of the material and is expressed in pounds per square inch.

** Life cycle assessment of windows for the North American residential market: Case study” by the University of British Columbia. Scandinavian Journal of Forest Research, 2008.

*** Estimated savings are based on data set forth in the Window Selection Tool of the Efficient Windows Collaborative, available at Actual savings will vary by product type, location, method of installation, individual home characteristics, local climates and conditions, utility rates, and other factors.

Ultrex® Performance

Cold, heat, and time – no worries

Ultrex® resists the ravages of cold, heat, time and pressure to provide the most worry-free windows and doors available today. While vinyl can distort in extreme heat or streak and crack in the fluctuating temperatures, Infinity products offer the highest level of performance and are virtually maintenance-free.

Low thermal expansion means a stronger seal

Ultrex® has an extremely low thermal expansion rate, which keeps the window stable and weathertight, reducing the risk of seal failures and air leakage into your home.




Tired of windows that are difficult to operate?

The low expansion of Ultrex® means Infinity Windows resist sticking, swelling, and warping, providing easy operation for the life of the window.


Tired of high-maintenance windows?

The low expansion of Ultrex® means Infinity’s patented finish stays looking like new and is virtually maintenance free. It resists discoloring, warping, rotting, corrosion, denting, rust and doesn’t require sanding, scraping, or painting.

Ultrex® Strength

Durability for a lifetime

Ultrex® is as strong as low carbon steel and 8x stronger than vinyl. It’s so tough we have to use diamond-edge blades just to cut it to size. The strength of Ultrex® translates into superior stability, long-term ease of operation, low-maintenance, and superior performance.



Infinity replacement windows and doors are made from Ultrex® fiberglass – a pultruded fiberglass material so strong and durable it is superior to other window materials. Best of all, it makes Infinity products virtually maintenance free.

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Ultrex® Appearance


A superior finish that outlasts the competition

Infinity´s patented, mechanically bonded finish is up to 3x thicker than competitive finishes. It provides superior resistance to scratching and UV degradation – even on darker colors.

The Ultrex® coating system is AAMA 623-10 certified meaning Infinity´s commercial grade finish resists the harshest weather conditions mother nature offers; a claim competitors can’t match.



The automobile industry learned decades ago that acrylic lights outlast the life of their vehicles. Infinity uses a similar acrylic finish to ensure long-term color retention and durability.


The difference is in the details

Vinyl windows can arrive with messy welded corners, and bulky profiles that reduce your view. Infinity windows arrive with clean mechanically-bonded corners, traditional details, and narrow profiles to maximize your view.


Infinity uses a patented, mechanically-bonded finish, compared to competitor’s thin painted finish that can expose the rough fiberglass material.

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Limited Time Spring Promotion

10% off 5 Windows or More! *on selected windows