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The window you never have to think about. Windows, doors and siding made from Ultrex retain their good looks and weathertight performance long after other windows and doors have reached the end of their useful lives - all without any grueling maintenance.

Stands up to the heat. Never backs down from the cold.

Ultrex pultruded fiberglass is specifically designed to withstand the rigors of time and our harshest climates. Where vinyl distorts or breaks down in extreme heat, Ultrex maintains consistent performance through the changes of seasons.

Minimal expansion for a stronger seal.

Because Ultrex matches the extremely low thermal expansion of glass, windows and doors maintain a stronger seal while reducing the risk of seal failures and air leakage into your home. Low thermal expansion means siding stays straight and tight for a weather barrier that is impervious to moisture.

833% less thermal expansion than vinyl.

Ultrex expands and contracts at a much lower rate than other window frame materials.

Virtually maintenance free.

The patented acrylic finish on Ultrex stays looking like new and requires little maintenance. It resists discoloring, warping, rotting, corrosion, denting, rust and doesn’t require sanding, scraping, or painting.

Slides now. Slides later.

The low thermal expansion means windows and doors made of Ultrex resist sticking, swelling, and warping, providing easy operation for the life of the product.