Ultrex® Fiberglass



Marvin® replacement windows and doors are made from Ultrex 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.

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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%.***


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.


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.



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 weather tight, reducing the risk of seal failures and air leakage into your home.

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Lower Cost of Ownership

Business Dictionary Online defines Total Cost Of Ownership as “The estimate of all direct and indirect costs associated with an asset or acquisition over its entire life cycle”

In our world of window and siding product selection “the true cost of any window or siding product is what it will cost to purchase PLUS any future cost to maintain that window or siding product. The performance, appearance and longevity are all taken into account when selecting the proper products for your next home improvement. We are fortunate to the be a Marvin Window and Door of Canada authorized dealer of HYBRID ULTREX FIBERGLASS products. Products proven to out perform, out last, increase your homes value and cost the lease amount in future maintenance cost. No maintenance, projected to last twice as long as other products = Lower Cost of Ownership