Cozy living room with stone fireplace, wooden furniture, and a rustic chandelier. A woman in a red dress interacts with a black and white dog. Large windows show greenery outside.

Fibrex® Windows: A Better Alternative for a Better Window

The introduction of Fibrex material is one of our most innovative ideas. Fibrex combines the strength and stability of wood with the low-maintenance features of vinyl. In 1992, Andersen patented this Fibrex material that today is the perfect choice for your new replacement windows.

Cross-section of a double-glazed window frame with multi-chamber design made with Fibrex material. Since Fibrex material is strong, frames can be made narrower than other framing materials, meaning more glass and more view.
"Engineered with Fibrex Material" text logo in bold font.

Benefits of Fibrex Material Compared to Other Materials

Comparison chart of Fibrex Material, Vinyl, and Wood properties for insulation, maintenance, decay resistance, rigidity, durability, color options, and dark color performance. Fibrex excels in all areas, while Vinyl and Wood have selective strengths.

  • STRENGTH - Due to the strength of Fibrex material, we are able to make our sash and frames narrower, which means more glass and more view.

  • INSULATION - Since Fibrex material is combined with Andersen High Performance Low-E4 glass, which helps your home stay warm in the winter and cool in the summer, it has superior thermal insulating properties. This also will help you save money on your energy bills.

  • LOW MAINTENANCE - The beauty of Fibrex material is that it never needs scraping or painting because it won’t rot, decay or mold.

  • EXCELLENT INSULATOR - Fibrex material has excellent insulating properties on a par with vinyl, fiberglass, and wood. Aluminum transfers heat out of your house and allows outdoor cold temperatures to chill the areas around your windows inside. Fibrex material insulates about 700 times better than aluminum.

  • DECAY-RESISTANT - Due to a special polymer formulation that surrounds and coats each wood fiber in the manufacturing process of Fibrex material, exceptional resistance is provided to rot and fungal growth. Renewal by Andersen’s windows that are made with Fibrex materials never need scraping or painting because they are backed by are warranty not to flake, rust, peel, blister, crack, pit or corrode.

  • DURABLE & RELIABLE - Fibrex material expands and contracts very little. Vinyl on the other hand, expands and contracts a lot, which can lead to cracking, bowing, and leaking of air and water. Fibrex material windows are able to perform better in every season no matter how cold the winters can be or how high the summer heat may be in your area.

  • STABLE & PREDICTABLE - Compared to vinyl, Fibrex material is twice as stable and rigid. The average stiffness of wood is higher, but is also less predictable then Fibrex material because of the natural variations of wood, like grain, knots and moisture content. Since Fibrex material is strong, frames are able to be made narrower than other framing materials, meaning more glass and more view. Fibrex material is able to be made into any style of window and in colors that complement every home.

Warranty badge for Renewal by Andersen with five stars, stating "Nation's Best Warranty Coverage" with full transferability and coverage for Fibrex material, installation, hardware, and glass.

A window is not supposed to be just glass and some framing material. It is a precise combination of glass, frame, and quality installation. We back all of our windows with a 20/2/10 Limited Warranty that is one of the best in the business.

LEARN MORE ABOUT OUR WARRANTY ❯

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