Windows and Doors

Fiberglass Windows and Doors

Exceptionally strong and durable, fiberglass window and door frames have low expansion and contraction rates with temperature changes, making them ideal for any climate.

Fiberglass Windows and Doors picture


If you are planning a project with large windows in mind, fiberglass is extremely strong and can hold expansive pieces of glass. Milgard regularly tests its fiberglass frame lineals for quality and long-lasting performance.

Fiberglass windows and doors are low-maintenance and resist swelling, rotting, warping and corrosion. They do not require repainting like wood, but the material is paintable if you prefer to change colors down the road.

Fiberglass windows are doors are very energy efficient with low thermal conductivity in your home, for year-round comfort you can rely on.

Strong and Built to Last

Fiberglass frames are composed of glass fibers and resin bonded together to create a long-lasting and weather-resistant material. These fiberglass components tolerate changing conditions like extreme heat and cold while resisting swelling, rotting, and warping that can occur with other materials. Manufacturers routinely test the popular fiberglass frame material for color uniformity, gloss, film thickness and chemical resistance to ensure unmatched quality and performance.
Fiberglass Windows and Doors picture
Fiberglass Windows and Doors picture

Durable Finishes

Milgard will only put our name on a window or patio door if it can live up to our standards. C650 Ultra™ Series windows and patio doors have fiberglass frames inside and out with four exterior colors available. Each exterior color can be paired with a white or a color-matched interior. Choose from Frost, Harmony, Bark or the popular Black Bean for the dark window look that is on-trend in homes today.

Inspiration Photos

Contact us today

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As certified dealers, we are invested in our community and dedicated to providing excellent customer service.

We work with you to select the best windows for your home’s architecture as well as your climate and lifestyle.

Let us help walk you through your replacement or new construction project at a more personalized level.