Renewal by Andersen® replacement windows are made of Fibrex®. These are the best replacement windows on the market.  The frame is made of materials similar to wood and vinyl, but do not have their weaknesses. 

What is Fibrex made of?

Fibrex material is a special composite made of wood fibers and polymer. With Fibrex, you can enjoy the strength and durability of traditional wood frames and the low maintenance requirements of vinyl. Our parent company Andersen® Corporation developed Fibrex as an alternative to wood frames and cladded aluminum in as early as 1958. The resulting material ultimately became patented in 1991.

Are all Renewal by Andersen window frames made of Fibrex?

Renewal by Andersen is the full-service window replacement division of Andersen Corporation. One of the first decisions made was to use Fibrex as the sole material for our window frames. As an extruded material, Fibrex gave us the capability to craft custom replacement windows in virtually any shape, size, and profile while maintaining consistent long-term performance and energy efficiency. Some of the patio doors we offer also feature structural components made of Fibrex material.

How can Fibrex help you save on your energy bills?

Much like wood, Fibrex has natural insulation. Combined with a chambered design, our window frames do not require an insulated foam core or something similar to slow down thermal transfer. Combined with our High-Performance™ Low-E4® glass, our replacement helps prevent heat from leaking through the windows and reduce your home’s heating and cooling requirements, which can lead to energy savings. Every Renewal by Andersen replacement window bears certification from ENERGY STAR®.

Is Fibrex eco-friendly?

Fibrex is produced with the environment in mind. It contains at least 40% wood fibers reclaimed from the wood trimmings at Andersen Corporation’s facilities in Minnesota — just down the road from our own. We have greater control over our supply chain and manufacturing, from sourcing the raw materials to shipping and installation, which helps us keep our carbon footprint as small as possible. The Fibrex material frames themselves are more sustainable, thanks to their expected life spans of more than 35 years, longer than most other window replacement products.