Fiberglass Windows
Fiberglass windows are practically maintenance-free. They take paint easily, do not warp, crack, rot, or corrode, and are extremely strong. Fiberglass is a composite structural material that consists of fiber reinforcements, typically glass, that are bound together in a resin matrix. The unique properties of fiberglass include:
- Thermal expansion similar to glass
- Low thermal conductivity
- Dimensionally stable
- High Strength
- Rot resistant
- Chemically inert
- Easily paintable
- Lower environmental impact
- Recyclable
Because it's made of glass, the frame expands and contracts at the same rate as the glass in the window which further reduces energy leaks. Additionally, fiberglass takes the least amount of energy to produce and has the longest life expectancy of any window frame material, which is why leading experts say fiberglass is the most environmentally-friendly choice available.
Pella WindowsFiberglass |
Marvin Integrity WindowsFiberglass |

















