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.

Material Properties
Fiberglass is an ideal window frame member.
  • Nearly 10x stiffer than traditional vinyl, allowing for larger window spans without reinforcing
  • Made from high resin-to-glass, thermoset fiberglass, the windows will not sag, weaken or creep over time
  • Can withstand extreme temperatures (-40°F through 350°F, and higher) without becoming brittle or soft
  • Made from non-organic, chemically inert pultruded fiberglass, the windows are not susceptible to corrosion, rot, insect damage or UV degradation
  • High condensation resistance helps improve window hygiene


  • Modeled lifespan of up to 80 years, representing significantly lower lifecyle embodied carbon compared to aluminum and vinyl