Why Fiberglass?

Future of Performance

Why Fiberglass?

Fiberglass is an ideal structural material for window and door frames, which is why Cascadia has used a proprietary, high glass-fiber-to-resin formula for more than a decade. Beyond its high strength and thermal efficiency, Cascadia's pultruded, thermoset fiberglass frames contain roughly 58% recycled content, low VOC's and represents less embodied energy compared to vinyl or aluminum. 

Not susceptible to decay or corrosion, fiberglass also expands and contracts with temperature change at roughly the same rate as the adjacent IGU. This extends the longevity of window seals and gaskets, reducing maintenance costs. Combined with a modeled lifespan of 50-80 years, fiberglass represents the future of high-performance windows and doors.

Thermal Performance
  • Boasts 100%-250% improved thermal performance compared to traditional aluminum windows, lowering heating and cooling costs


  • Inherently low-conductive material doesn’t require addition thermal breaks

  • Frame voids are filled with high-density insulation to further improve thermal performance
  • Thermal movement coefficient of fiberglass is similar to glass, meaning less stress on sealant joints and gaskets and extended product life



  • Passive House certified configurations available, including fixed and operable windows, plus swing and sliding doors