Our revolutionary Fibrex composite material combines the strength and stability of wood with the low-maintenance features of vinyl.

Andersen Corporation created Renewal by Andersen to change the window replacement industry – not only with a different and better process – but also with an innovative new material to make the frames. In 1992, Andersen perfected and patented Fibrex® composite material technology.

Fibrex® material is a better window framing material for several reasons:

1. Because it is a composite using real wood fiber, it is very strong. This means narrower frames which, in turn, means more glass area. Vinyl frames are often thicker, reducing glass area.

2. As a low-maintenance composite, it expands and contracts very little, even with extreme temperature swings. This means we can offer dark exterior colors that vinyl can't because Fibrex® material can "take the heat" (150°F).

3. Due to this material difference, Renewal by Andersen can offer one of the best window limited warranties in the industry.*

Consider everything you expect from a window. Fibrex material makes a difference in every instance. Measured across a range of conditions that affect efficiency, maintenance and beauty, Fibrex material performs well compared to wood, aluminum and fiberglass, and especially well against vinyl. 

 Download our Fibrex® material brochure to learn more about this amazing material.

* See limited warranty.

Learn more about Fibrex, the exclusive composite material that makes Renewal by Andersen windows a better choice.