Ultrex fiberglass has an amazing strength-to-weight ratio, which is one of the reasons why it’s the material of choice for boats, bridges, guard rails, and ladders. It’s highly durable, doesn’t corrode, resists rot, and resists expanding and contracting in temperature swings. In comparison to longitudinal tensile strength.
What Is Pultrusion?
Pultrusion is a highly precise manufacturing process that combines the words “pull” and “extrusion.” It continuously pulls fiberglass strands through a heated die, forming rigid profiles with exceptional dimensional stability and strength. This process is ideal for creating durable, lightweight components used in everything from construction and bridges to Infinity’s industry-leading window frames.
The Ultrex® Pultrusion Process Explained
Infinity from Marvin windows are made using a proprietary fiberglass pultrusion process that ensures superior strength and long-term performance. Fiberglass fibers are reinforced with thermosetting resins—materials that, once cured with heat, undergo a permanent chemical change. This makes the resulting window frame exceptionally strong, stable, and resistant to deformation. With Ultrex®, you get precision-formed fiberglass that stays true to shape and resists expanding and contracting over time.
Pultruded fiberglass is composed of glass fibers and durable resins. The process begins with finely ground raw materials—primarily Silica and Zirconia—melted at around 1500°C. The molten glass is drawn into ultra-fine filaments, bundled into strands, and heat-cured into rovings. These strands are then used to form the backbone of Infinity’s Ultrex® fiberglass—delivering exceptional longitudinal strength and rigidity to each window profile.
The resin used in Ultrex fiberglass is typically a high-performance polyester. This type of resin offers excellent strength, adhesion, and resistance to chemicals. During the pultrusion process, these resins are carefully blended with pigments and fillers to create a strong, stable matrix. The result is a low-maintenance, high-strength fiberglass frame that delivers exceptional performance in any climate—including Colorado’s extreme temperature swings.
Award-Winning Legacy of Customer Satisfaction
Infinity from Marvin has a long-standing reputation for excellence—including top honors in past customer satisfaction studies. In 2019, Infinity earned the #1 ranking in the J.D. Power Windows and Patio Doors Satisfaction Study based on customer feedback in three key areas: appearance and design features, operational performance and durability, and warranty.
While the study was conducted several years ago, it remains a testament to Infinity’s commitment to quality and service—values we continue to uphold at Gravina’s Window Center of Littleton®.
“We’re not focused on being the biggest window and door replacement company — we’re focused on being the best.”
– Dan Marvin, President of Infinity from Marvin (2019)
Infinity earned a satisfaction score of 890 out of 1,000, based on feedback from 2,913 homeowners surveyed between January and May 2019.
