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Buy 2 or More Marvin™ Windows   Get 10% Credit Towards TrimFiberglass Windows at Lee Lumber

In recent years, fiberglass has become more popular as a window framing material. Fiberglass can offer significant advantages over traditional window framing materials in both thermal and structural capacities. In particular, its high strength-to-weight ratio makes fiberglass an ideal choice for larger windows.

The Advantages of Fiberglass

Fiberglass has three main advantages: high strength, low thermal conductivity, and superior durability. Fiberglass is about 70% lighter than aluminum and weighs 30% less than copper or steel. Its strength-to-weight ratio is far greater than any other material used to build new windows, making it an ideal material for building larger windows. Thermal conductivity is a measure of how well a material absorbs heat from or releases heat to its environment. Fiberglass has a thermal conductivity that is approximately 800 times less than that of aluminum. This means that fiberglass is considered a super insulating material and that windows made from it are exceptionally energy efficient. This also means that fiberglass windows have a low rate of thermal expansion. In fact, the thermal expansion of fiberglass is almost identical to that of standard glass, which helps to maintain a window’s structural integrity over time, minimize warping, and reduce seal failure. Fiberglass windows last up to 38% longer than windows made of other materials. As an added benefit, the high strength of fiberglass means that frames and mullions on fiberglass windows can be smaller and thus these windows have a larger glass-to-frame the ratio. This increases the maximum sunlight and viewing area. Fiberglass is exceptionally resistant to corrosion. In particular, fiberglass can withstand corrosive salt such as is found in coastal regions. Adding to of the benefits of fiberglass in coastal regions is the fact that pultruded (a continuous molding process) fiberglass can distribute an impact load and thus resist serious damage. Many fiberglass windows are rated for impact from moderate-sized debris traveling at as much as 140 miles per hour.

Manufacturing Pultruded Fiberglass Windows

Pultrusion is a manufacturing process used to produce continuous lengths of a reinforced polymer. The process involves pulling, rather than pushing, raw materials through heated forms. In the case of fiberglass, flexible glass fibers are mixed with a liquid resin to produce an incredibly strong but lightweight baseline material. This rigid material can then be cut and formed to produce window frames. Once the fiberglass has been formed, it can be powder coated to look much like painted wood. Standard colors like white, tan, and brown are almost universally available. Premium manufacturers also produce other colors. In general, if a color is available as a powder coat, it can be applied to a fiberglass window.

Buy 2 or More Marvin™ Windows   Get 10% Credit Towards TrimBrands Producing Fiberglass Windows

Marvin’s Integrity line of windows, featuring Ultrex® fiberglass, is among the most durable of all fiberglass windows on the market. Eight times strong than vinyl and at least three times stronger than wood, Ultrex® windows are specifically marketed for high-performance applications. When combined with IMPACT glass, Ultrex® windows can withstand a 2 x 4 traveling at 50 feet per second and hurricane-force winds up to 140 mph. Ultrex® windows are also resistant to fading, chalking, peeling, and cracking.

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