Andersen® products and patents have revolutionized the window and door industry for more than 100 years. We know windows and window materials.

In 1958, Renewal by Andersen’s parent company Andersen Corporation, tested and rejected aluminum as a framing material. It conducted heat and cold, plus it could pit and corrode. Also in the 1950’s, Andersen developed the first hollow vinyl window in the U.S. We liked the low maintenance feature of vinyl, but concluded that it didn’t have enough structural integrity. In 1966, Andersen created the “wood-clad” window and door category with the Perma-Shield® line of products.In the 1970’s, Andersen began experimenting with reclaimed wood fibers. In 1991, after decades of development and testing, Andersen patented and introduced Fibrex® material, a composite of wood fibers and polymer. Fibrex material combines the strength and stability of wood with the low-maintenance benefit of vinyl and contributes to whole window performance.Fibrex® material has excellent insulating properties on par with wood, vinyl or fiberglass. Aluminum, on the other hand, transfers heat out of your home and allows outdoor cold tempertures to chill the glass inside it. Fibrex material insulates about 700 times better than aluminum.Fibrex material, like wood, fiberglass and aluminum expands and contracts very little. Vinyl, however can expand and contract a lot, which if not designed properly may cause cracks, bowing and leakage of air and water, leading to the need for replacement windows. Windows made of Fibrex material will perform better in winter and summer than windows made from vinyl.Renewal by Andersen® windows made with Fibrex® material also meet the strictest indoor air emission standard in the U.S. and contain certified recycled content.** Renewal by Andersen and its parent company, Andersen Corporation, are the only window companies to receive Scientific Certification Systems (SCS) Indoor Advantage Gold™ certification for indoor air quality. This level of certification conforms to the criteria of a number of North America’s indoor air emission standards, including the California 01350 standard, recognized as among the strictest in the U.S.** Renewal by Andersen windows have certified recycled content values range from 19%-23% and vary by product line.Contact a Renewal by Andersen consultant to learn more about Fibrex or to schedule a free home estimate.

Recent Blogs

Which Replacement Windows and Doors Are Best for Rural Kentucky and Southern Indiana?

Rural KY & Southern Indiana homes need windows and doors that beat heat, humidity, and storms. See how Renewal by Andersen's replacement Fibrex® windows and doors deliver.

The Real Cost of Replacement Windows for Kentucky and Southern Indiana Homeowners

Wondering if replacement windows are worth the cost in Kentucky or Southern Indiana? Discover what your old windows are actually costing you every month in energy bills and HVAC wear — and how the right replacement windows can start saving you money long term.

Southern Indiana & Louisville's Heat Dome Is Here: How Renewal by Andersen Replacement Windows & Doors Keep Your Home Cooler This Summer

Beat Louisville's heat dome with Renewal by Andersen replacement windows and doors. Discover how Fibrex® frames block heat and humidity, lower AC strain, and cut energy bills—plus quick tips to cool your home now.