PELLA® IMPERVIA® Fiberglass Windows

Why Choose Fiberglass Windows?

Pella’s fiberglass windows are made of the strongest, most durable material available in windows.17 Our patented, low-maintenance fiberglass is scratch-resistant and can withstand extreme heat and subzero cold temperatures, so you can trust our fiberglass windows to perform in your home.
Pella® Impervia® fiberglass windows offer superior strength and durability. Enjoy the enduring beauty of fiberglass awning, casement, sliding, single-hung and double-hung windows — backed by one of the strongest warranties in the business.

Casement Windows

Double-Hung Windows

Single-Hung Windows

Sliding Windows

Awning Windows

Why Fiberglass?

  • Superior strength and durability with patented fiberglass material
  • Withstands the most extreme temperatures
  • Long-lasting powder-coat finish, including Black
  • Sleek, timeless profiles
  • Meets the rigorous performance requirements of a commercial building

Performance Enhancements

  • Optional foam insulation for better energy performance
  • Exceptional energy efficiency
  • Innovative locking system for improved security and a stronger seal
  • Patented unison locking system, with one easy-to-use lock-lever


Made from our patented five-layer fiberglass material, Pella Impervia windows are on average 100x more impact-resistant than a leading wood/plastic composite product. Tested from -40ºF to 180ºF, these windows can withstand some of the harshest conditions, making them strong and incredibly energy efficient.
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What Our Clients Say About Working With Us
 Very good experience with roof replacement. Comfortable to work with. 
 We are so pleased with Brandon and his crew. They are very respectful, courteous. and committed to doing an excellent job. I would recommend Core Exteriors with 100 percent confidence that they will do a great job. 
 Very easy to work with. Quality job Was done on time as promised. I would highly recommend! 
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Core Exteriors

15370 290th Ave NW
Zimmerman, MN 55398
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Experience is key when choosing a contractor.

CoreExteriors BuildZoom score of 107 ranks in the top 4% of 77,973 Minnesota licensed contractors, which places them above 96% of 77,973 contractors in Minnesota.

How is the BuildZoom score calculated?
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  • Work experience
  • Customer feedback
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