Ultrex® Fiberglass can take the heat or the cold

Constant expansion and contraction can gradually break down windows and doors, causing poor operation, leaky seals and a loss of structural integrity. Ultrex expands at virtually the same rate as glass and maintains a tight seal, so it’s resistant to leaks, seal failures and stress cracks that can compromise energy efficiency and long-term performance.

Ultrex is a thermoset material that is cured and hardened into a shape, like concrete. This curing process is an irreversible chemical reaction, which means windows and doors made of Ultrex will not melt or lose their true shape even when exposed to extreme temperatures of up to 350°F.

Ultrex expands and contracts at virtually the same rate as glass to resist seal failures that can compromise energy efficiency.

Ultrex Fiberglass Performs in All Types of Weather

Vinyl Does Not

Vinyl and vinyl/wood composites (Andersen’s Fibrex®) are thermoplast materials, meaning they have the potential to change shape when they are exposed to extreme temperatures. In extreme heat, they can soften, melt, sag and reform. In the cold, they can become brittle and break.

Thermal Conductivity

Windows with low conductivity reduce heat loss in homes, which translates to lower energy bills. Ultrex is 500 times less conductive than roll-form aluminum, so homes retain more heat in the winter and stay cooler in the summer.

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