Marvin Materials Elevate And Essential Collection Ultrex Fiberglass Finishes


Marvin is a pioneer and leader in the use of premium composite materials for windows and doors. Over 20 years ago we introduced our proprietary Ultrex® fiberglass. Today, we also use Marvin High-Density Fiberglass for the exteriors of our Modern products.

Marvin Fiberglass Windows and Doors

Benefits of Fiberglass

  • Highly impact resistant and more rigid than vinyl and vinyl/wood composites
  • Expands and contracts at virtually the same rate as glass, so it works with glass rather than against it
  • Maintains shape even in harsh climates with regular exposure to temperature variation, wind, rain, or snow
  • Resists chipping, chalking, or fading, even in darker hues
  • Non-conductive and non-corrosive
  • Engineered to maintain its look even years after installation

The Marvin materials difference: fiberglass

Fiberglass is a composite material. Composites are made by combining two or more materials with different properties to create something superior to the materials on their own. Within the composite each of the materials are easily distinguishable and do not dissolve or blend together.

When considering a composite material, it is important to know that not all composites are created equal. Some companies use materials such as wood fibers and vinyl to produce a composite whose components have fundamentally different properties and performance values. With such different materials grouped in the composites category, it becomes important to know what sets them apart.

Thermoplastic vs Thermoset

Most plastics, vinyls, and vinyl-based composites like Fibrex, are made using thermoplastic methods which melt the material, pour it into a form and allow it to harden. When thermoplastic materials are then re-heated in the sun, they begin to re-melt. When it comes to products like windows and doors, this can mean that the product, especially in hot climates, begins to misfit the opening, making it hard to open and close, or that the seals become compromised in a relatively short period of time.

Marvin pultruded fiberglass is a thermoset material created through a chemical process. It is fundamentally more than the sum of its parts by the end of the manufacturing process. A thermoset fiberglass composite won’t soften or melt when exposed to environmental temperatures. As a result, it is more resistant to pressure and temperature than vinyl-based composites.

The Finishing Process

The Ultrex fiberglass finish on Essential and Elevate exteriors, and the High-Density fiberglass finish on Modern exteriors have been verified against the AAMA 624 finish requirements related to fading, chalking and gloss retention.

Ultrex and Marvin High Density Fiberglass

Ultrex and Marvin High Density fiberglass are both composites and share many of the same attributes and benefits. The added strength of our High-Density fiberglass makes it possible to create the thin profiles that can support extra-large spans of glass that are often the hallmarks of Modern design. The Marvin High-Density fiberglass is a great example of our ability to develop the right material for the right application, and the important role materials have in the aesthetics and performance of windows and doors.

Explore our product lines that use fiberglass

Additional Resources