Sales-speak decoder
Fibrex
Andersen/Renewal by Andersen's proprietary composite frame material — a blend of wood fiber and PVC. A real material, marketed as a category of its own.
What it means for you
Compare it on the numbers (U-factor, SHGC, warranty), not the trade name. It competes with other composite and fiberglass frames; whether it's worth its premium depends on the quote, not the branding.
Where you'll see it
Central to a Renewal by Andersen pitch.
Don't be fooled
A branded material name is still just a frame — hold it to the same spec questions as any other.
Related terms
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