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Ultrex® fiberglass leads fastest-growing window category


Fiberglass segment set to grow 64% by 2015; Ultrex grabs more than half the sales

WARROAD, Minn., Jan. 21, 2013 – More architects, contractors and homeowners are choosing durable, beautiful fiberglass windows and doors, making fiberglass the fastest-growing material in the window and door market. According to Ducker Worldwide, a leading B2B research firm, sales of fiberglass windows are projected to grow 64 percent by 2015.

Marvin Windows and Doors pioneered the fiberglass segment nearly 20 years ago and still leads the category, taking more than 50 percent of all sales in the fiberglass market with its Integrity and Infinity lines of windows and doors. Ultrex also lends its strength and beauty to Marvin’s innovative Apex line of fiberglass siding and trim.

There are good reasons why fiberglass is growing so quickly – and why Marvin’s Ultrex pultruded fiberglass is at the head of the class:

  • Fiberglass doesn’t soften with heat or grow brittle with cold. By contrast, vinyl and vinyl/wood composites like Fibrex® are far more susceptible to deformation and damage from extreme conditions.
  • Fiberglass is many times stronger than vinyl or composites like Fibrex. The tensile strength of Ultrex is nearly six times that of vinyl and more than seven times that of composites.
  • Ultrex is the only product in the fiberglass, vinyl or composite category whose finish is certified for quality and durability by the American Architectural Manufacturers Association (AAMA).
  • Fiberglass windows can be built with thinner, stronger frames than vinyl or composites like Fibrex, allowing larger openings and more daylight.
  • Ultrex fiberglass is available in a wide range of colors and is paintable, allowing homeowners to choose any color they desire with no decrease in performance.

“Homeowners who want beautiful, durable, virtually maintenance-free windows and doors should look into the benefits of fiberglass,” said Brett Boyum, vice president of marketing for Marvin Windows and Doors. “It’s no accident that fiberglass is the fastest-growing category in the window and door industry. And Ultrex has a longer track record than any other fiberglass product on the market. We like to say that Ultrex fiberglass just might be the perfect building material.”

Strong, stable, durable and virtually indestructible, Ultrex fiberglass is possibly the perfect building material, creating windows and doors that leave other materials in the dust. Made from pultruded fiberglass, Ultrex outperforms vinyl on nearly every measure. Learn more at

Marvin Windows and Doors brings its Built around you® philosophy to life with every customer and every solution.  A premier manufacturer of made-to-order wood and clad wood windows and doors, Marvin offers the industry’s most extensive selection of shapes, styles, sizes and options to fit the diverse needs of builders and match the personalities of homeowners.

Marvin’s tradition of delivering the finest craftsmanship in windows and doors began in Warroad, Minn., a small town just six miles from the Canadian border, where the privately-held, family-owned and operated company is still headquartered today. Learn more at

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