Ultrex® Fiberglass

Weber Windows was hand picked by Marvin to be the exclusive, installing retailer for the Infinity from Marvin fiberglass products for the Louisville area. These products are regarded by many leading industry experts to be THE replacement window for durable, long-lasting, high performance results.

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.

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.**

* 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.

Strength for an expanded view

Take a moment to look at the images below. The Infinity view is expanded — how? The superior strength of Ultrex also allows for a narrower window frame profile and more glass area than other replacement windows, giving you more daylight and better views.

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 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® Appearance

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.

A superior finish that outlasts the competition

Our 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.

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


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.
Share