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Fiberglass Windows and Doors
Marvin has been a pioneer in the development of fiberglass as a premium material for windows and doors. The properties of fiberglass are ideal for creating strong, durable, energy efficient products that stand up to harsh elements and everyday usage.
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Benefits of Fiberglass
Because of its strength, fiberglass windows and doors are able to meet structural performance requirements with narrow, streamlined profiles that create an uncluttered aesthetic with less frame, more glass, and bigger views. This strength, coupled with its low conductivity of heat and cold, creates a premium, high-performance material perfectly-suited for windows and doors.
Exceptional Strength
Fiberglass windows and doors resist bending and flexing to protect the integrity of the home.
Structural Stability
Does not expand and contract with dramatic changes in temperature, making fiberglass windows and doors resistant to leaks, seal failures, and stress cracks.
Premium Finish
Fiberglass is virtually maintenance free – no sanding, scraping, or painting is needed.
Energy Efficiency
The low thermal conductivity of fiberglass combined with energy efficient glass options helps manage the amount of light and heat entering and leaving the home.
Fiberglass Window and Door Collections
Modern Collection
See how the Modern line is stunning in both its design and engineering, letting you take the best of modern design and create this aesthetic at an even larger scale.
Vivid Collection
Complement transitional to contemporary architecture with dramatic sizes, durability, and energy efficiency.
Elevate Collection
Find the most in-demand traditional window and door types with natural wood interiors and Ultrex® fiberglass exteriors.
Essential Collection
Choose from a streamlined selection featuring proprietary Ultrex® fiberglass inside and out.
Why Choose Marvin Fiberglass Windows and Doors
Not all composite materials are created equal. The fiberglass used in Marvin windows and doors is made with lineal fiberglass and thermoset plastics. This is what sets Marvin fiberglass apart from composites made with sawdust, vinyl, and other low-cost materials.
Highest Quality Materials
The high percentage of lineal fiberglass in Essential, Elevate, Vivid, and Modern products contributes to the long-term performance. Because of the high concentration of glass, Marvin fiberglass expands and contracts very little regardless of the changing temperatures. This stability means fiberglass windows and doors are less likely to experience seal failures, leaks, and stress cracks.
A Finish That Lasts
Marvin fiberglass offers a premium, smooth finish – unlike rough textured finishes on some competitive composite products. Ultrex features an acrylic finish* that is bonded to the fiberglass through a proprietary process. The Ultrex finish protects against fading, chalking, and gloss retention. The Marvin High-Density Fiberglass finish is baked on at extremely high temperatures resulting in a finish that exceeds a high-quality aluminum car paint.
Category-Leading Strength
Ultrex fiberglass is 7x stiffer than vinyl and 4x stiffer than vinyl/wood composites. Fiberglass is incredibly rigid, which makes it highly impact resistant and capable of standing up to everyday wear and tear, especially in extreme weather conditions.
Fiberglass frames and sashes are less likely to bend and twist, helping protect the structural integrity of your home.
Superior Process
Ultrex and Marvin High-Density Fiberglass are created through a process called pultrusion. Pultrusion makes it possible for long, lineal glass fibers to become embedded and highly concentrated in the fiberglass as it is pulled through a dye. This high concentration of glass fibers results in superior strength and an exceptionally smooth and durable finish.
Fiberglass Windows and Doors FAQs
What is Ultrex fiberglass?
A strong, durable, fiberglass proprietary to Marvin. Used for the exteriors of Elevate and Vivid products and the interiors and exteriors of Essential products.
The finish is AAMA 624 verified, which means it has undergone rigorous tests that simulate the difficult conditions a finish can encounter throughout the life of a window or door.
What is High-Density Fiberglass?
– A fiberglass that shares many of the same characteristics of Ultrex but is even stronger
– Used for the exteriors of Modern products
– Mimics the clean look, feel, and strength of aluminum and steel with better insulating qualities
– The High-Density Fiberglass finish is currently undergoing the AAMA 625 verification process.
What is fiberglass reinforced composite?
Featured on the interiors of Marvin Vivid windows, proprietary fiberglass reinforced composite offers a premium acrylic-based finish for low-maintenance beauty that lasts. The tensile strength of fiberglass reinforced composite is 2x stronger than vinyl and wood/vinyl composites.
What’s the difference between fiberglass and vinyl windows?
Ultrex and Marvin High-Density Fiberglass are fundamentally different materials than vinyl with entirely unique properties. Fiberglass is a much stronger material than vinyl due to the base materials that make up fiberglass as well as the process by which fiberglass is created. Fiberglass is significantly more resistant to expansion and contraction, dents or cracks, making it a far more resilient material for windows and doors. In short, it’s able to stand up to daily wear and tear better.
Vinyl has a hard time standing up to extreme temperatures, which can weaken the integrity of a window or door, making it more susceptible to water leaks, poor window seals, and overall loss of shape and energy efficiency.
Fiberglass is a superior material for building strong, durable windows and doors. Fiberglass is also more fade-resistant and able to handle high temperatures, which is why it is available in darker colors. Contact your dealer to learn more.
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Find a Dealer
Connect with a Marvin dealer today to learn more about how Marvin windows and doors can work for your project.