<iframe title="Google Tag Manager" src="https://www.googletagmanager.com/ns.html?id=GTM-8CXX" height="0" width="0" style="display:none;visibility:hidden"></iframe>
Skip to Content
Pella
three windows for testing andersen fibrex pella impervia fiberglass

    Pella Fiberglass vs. Andersen Fibrex

    It's a One-Sided Fight – Spoiler Alert: Pella Wins

    See how our exclusive fiberglass material outperforms Andersen Fibrex plastic/wood composite to hold up better for the strength and durability your home or project demands.

    Won't Bend
    Pella fiberglass is on average
    7.8x

    stronger than Fibrex in a bend test.33

    Won't Dent
    Pella fiberglass is on average
    73x

    more impact resistant than Fibrex.27

    Won't Break
    Pella fiberglass is on average
    19x

    the tensile strength of Fibrex.34

    Compare the Superior Strength of Pella Fiberglass vs. Andersen Fibrex

    As much as the competition in a bend test, which measures the flexural strength of a material by applying force via a single, concentrated load point in the middle.
    Loading

    3-point bend testing performance based on testing 10 samples of each material using ASTM D790 test methodology.

    Pella® Impervia® – 100% Fiberglass. 0% Wood Fiber.

    Take a look behind the paint and see what materials make up Pella's proprietary fiberglass and Andersen Fibrex.

    a close view of pella's fiberglass material

      Pella Impervia, made of our proprietary fiberglass

      Our fiberglass starts with our structural mat which places rovings in a specific, intricate order to meet Pella’s high strength standards. The mat and additional rovings are pulled through a machine, injected with polymer resin and heated to create an entirely new, thermoset material. Our fiberglass material is the strongest available for windows and patio doors.9

      andersen's fibrex material failed the hammer test

        Andersen Fibrex, made of plastic, wood fiber and glue

        Contrary to popular belief, Andersen Fibrex is not fiberglass, but is instead made of 40% wood fibers and 60% plastic that is fused together with glue to create the window or door frame. Without strong fiberglass rovings and mats, this thermoplastic material used on Andersen 100 Series and Renewal by Andersen Fibrex products is susceptible to breaking and shattering.

        Schedule a Free In-Home Consultation

        alarm 90 Minutes

        A Pella expert will come to your home to discuss project needs and options.

        • See design, material and color options
        • Measure your windows and/or doors
        • Explain the installation day process
        • No-obligation quote for your project

        In-Home Consultation Promotions

        See how we simulated a slipping hammer on a jobsite to see the damage.

        01:43

        Testing our Fiberglass to the Extremes

        01:34

        Pella Fiberglass vs. A Bowling Ball
        More Extreme Tests
        testing material by dropping a volleyball onto a piece of fiberglass material
        Pella Fiberglass vs. A Bowling Ball
        Now Playing
        testing material hanging cinder blocks off a piece of fiberglass frame
        Behind the Bend Test
        testing material by hanging a pickup truck from a window frame
        Strong enough to lift a heavy-duty truck
        See How Our Fiberglass is the Best Fiberglass for Your Project
        Pella vs Marvin

        Strategic Woven Fibers vs. Basic Random Fibers

        Pella vs Milgard

        Strategic Woven Fibers vs. Basic Random Fibers

        A child plays with toys by a large black fiberglass window in a bright, modern room.
        Get the Best Fiberglass Windows & Patio Doors

        Designed to stand up to everyday wear and tear, Pella Impervia products offer an on-trend color palette, including black, and feature our latest innovation, the Easy Slide Operator window hardware, winner of Best in Show at the 2021 International Builders Show.

        Explore Additional Product Details

        Ready to take the next step?

        Work with a dedicated Pella representative every step of the way.

        I'm a ProI'm a Homeowner