Fiberglass is awesome.

All of our products feature fiberglass frames, because fiberglass windows and doors have many life-cycle performance advantages over traditional framing materials.

Why Cascadia’s Fiberglass?

  • It is almost 10 times stronger than vinyl/PVC, and has a similar strength to Aluminum, so can achieve large spans and be used in commercial applications.
  • It is 8 times more stable from expansion and contraction than PVC, and therefore, does not cause stress on the joints, seals, and gaskets - meaning your window stays leak-free longer
  • It is approximately double the thermal performance of aluminum, sometimes even better than double
  • It is not susceptible to decay, mildew, UV degradation, or corrosion, which makes it is ideal for all climates and exposures.
  • It has at least double the life span of PVC - the expected life span of fiberglass is 50+ years

See the expanders below for much more information on the many benefits of fiberglass.

  • Material Properties

    Fiberglass is an ideal window frame member.

    It has been called ‘the lumber of the future’ and ‘the ultimate window frame’ for good reason: no other framing material can match its performance. Some of these benefits are listed below:

    Fiberglass is extremely strong and stiff – eight to ten times stronger than vinyl. It can accommodate higher wind loads with less deflection than is common with vinyl systems, permitting larger windows. It can withstand extreme temperatures (-40°F through 350°F, and higher) without becoming brittle or soft. Fiberglass frames rarely need structural reinforcement to meet strength and deflection performance criteria.
    Fiberglass is a dimensionally stable, thermoset material. This means that, once its thermoset resin has cured, it will not creep. Thermoplastics such as vinyl will creep and deform over time.
    Fiberglass is inorganic and chemically inert. This means it is not susceptible to rot or decay, mildew, insect damage, or UV degradation. It will not corrode or fade like other window materials.
    Fiberglass is an ideal paint substrate, with virtually unlimited potential colors. It is durable and easy to retouch or refinish, whether by hand to repair minor damage, or as part of a larger renewals project.
    Fiberglass frames also provide superior thermal performance, high condensation resistance and low thermal movement. Durable and efficient, they offer economic as well as environmental benefits - find out what fiberglass windows and doors can offer your next project!
  • Environmental Benefits

    Fiberglass frames are resource-efficient as well as energy efficient.

    The key environmental benefit associated with the use of fiberglass windows and doors is their enhanced energy performance. In appropriately insulated wall assemblies, energy efficient glazing can make a significant contribution to reducing energy consumption in buildings. Energy used to heat and cool buildings is a major contributor to green house gas emissions in North America.

    Fiberglass frames are also lightweight and have low embodied energy, compared to many commonly used window frame materials. They are made of non-toxic materials, safe to handle and eventually dispose of.
  • Thermal Performance

    Fiberglass provides low levels of conductivity without the need for thermal breaks.

    Fiberglass frames are more energy efficient than aluminum or vinyl windows, allowing less heat or cold to travel through the frame material itself. Fiberglass significantly outperforms even the best thermally broken aluminum windows (as shown below):

    Since it does not usually require reinforcement, fiberglass is also less conductive than typical vinyl window configurations. The steel added to reinforce vinyl frames reduces their energy performance – losing up to 20% of their R-value – and makes the frames feel colder, in winter conditions. Fiberglass frames are more energy efficient and feel warmer in winter conditions (as shown below): 

    Thermal modeling demonstrates the superior efficiency of fiberglass frames, compared to reinforced vinyl or aluminum. The window sections at left use identical glazing units, but the fiberglass frames are shown to be warmer in cold winter conditions, with reduced heat loss and improved condensation resistance.

  • Condensation Resistance

    Fiberglass provides excellent condensation resistance.

    The same characteristics that give fiberglass window frames their enhanced energy performance also provide superior resistance to condensation, as shown below:

    Condensation Resistance values for standard Cascadia products are in the 53 to 61 range (NFRC method) - see Energy Ratings for details.

  • Thermal Movement

    The thermal movement coefficient for fiberglass is very similar to glass (because it's made from glass), and to other traditional building materials.

    This means that, as building materials expand and contract with changing temperatures, there is less stress on sealant joints and gasket seals between fiberglass frames and other building materials, compared to aluminum or vinyl frames. The thermal movement coefficient for vinyl can be more than seven times greater than traditional materials (as shown below), stressing joint materials and creating more opportunities for IGU seal failure and leaks.

  • Envelope R-value comparisons [PDF] - 45KB

    Where minimum R-values are set by code, high percentages of glazing may only be possible with high-performance fiberglass windows. This graph compares the impact of four different window types (aluminum vs fiberglass) on overall building R-value, showing that Cascadia windows can significantly increase the overall R-value of the building enclosure.
  • White Paper - Why Fiberglass? [PDF] - 865KB

    Tackling the dilemma of energy performance & windows: Understanding how fiberglass windows deliver highly livable spaces, while dramatically increasing a building’s energy efficiency and reducing energy consumption.
  • High-Performance Windows

    A short video on the advantages of high-performance fiberglass windows.