Infinity windows and doors are designed to make a lasting impression. Their patented Ultrex® pultruded fiberglass with acrylic capping offers superior strength, durability, and thermal efficiency for any climate or environment - perfect for creating beautiful homes that stand the test of time!


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 process that allows for the precision production of parts with consistent strength and dimensional accuracy. By combining "Pull" and "Extrusion," it ensures high quality components made from advanced materials like Fiberglass or Resin are produced accurately while maintaining their durability, making them well suited to areas such as engineering or construction.


What is the Pultrusion Process?

Fiberglass materials used in the manufacturing of Infinity from Marvin replacement windows go through a pultrusion process. Pultrusion is a continuous molding process using fiber reinforcement in polyester or thermosetting resin matrices. Heat is used on the "thermoset" resins, in the fiberglass pultrusion process, to cause an irreversible chemical reaction which permanently sets the shape of the fiberglass window frames. With Ultrex, you can trust the curing process to be a one-way street - irreversible and permanent.


pultruded fiberglass windows and doors denver


Pultruded fiberglass materials are made of glass fibers and resins. The glass used in fiberglass, while basically the same core material as that used in flat glass, comes in a different form – rovings – or also known as fibers.  This form of glass begins as a finely ground, flour-like material composed of Silica and Zirconia. The "flour" is heated and melted at approximately 1500° C, and the resultant molten glass is passed through small holes forming hair-like filaments. The filaments are collected together, grouped and a binder is applied to bond them into strands. Then the strands are heat cured, wound together and rolled up into a cylindrical package. These fibers provide the bulk of fiberglass profile's longitudinal strength.


pultruded fiberglass windows and doors


The majority of resins used for fiberglass window profile are classified as polyesters. Polyester resin is one of a group of synthetic resins which undergo polymerization during curing. They provide excellent adhesive properties, high strength, and good chemical resistance. These high-performance polyester resins are then mixed with suitable fillers and pigments to formulate the resinous matrix. The formulations are optimized for the particular application.


1. Increased Strength (fiber processed under tension)

2. High Fiber Content

3. Low Expansion

4. Consistent Quality


With Infinity from Marvin Ultrex Pultruded Fiberglass, you can trust that it will stand up to anything Mother Nature throws your way. Gravina's Window Center of Littleton has five decades of window installation experience and an unwavering commitment to quality materials which ensures a strong product that won’t let you down! Get access to the best fiberglass windows solutions today—along with our friendly service and support every step along the journey. Don't miss out on these incredible windows; explore what Infinity can do for your home!



Infinity from Marvin Ranked #1 in J.D. Power Study

The window and door replacement line received top honors in customer satisfaction study.

Infinity from Marvin earned number one for customer satisfaction in J.D. Power 2019 Windows and Patio Doors Satisfaction Study in the manufacturer segment. The study measures satisfaction among customers based on performance in three factors: appearance and design features; operational performance and durability; and warranty.

Infinity from Marvin ranked highest with a satisfaction score of 890 based on a 1,000-point scale.

"We’re not focused on being the biggest window and door replacement company — we’re focused on being the best,” said Dan Marvin, President of Infinity from Marvin. “Earning the number one position on the J.D. Power customer satisfaction study is wonderful recognition of our team’s continual efforts to make every step of replacing your windows as simple as possible and backing it up with innovative products and timeless design."

The global leader in consumer insights surveyed 2,913 customers in three performance areas who purchased windows or patio doors within the previous 12 months. The study was fielded January – May 2019. For more information about the J.D. Power 2019 Windows and Patio Doors Satisfaction Study, visit jdpower.com/awards.