Think Performance, Think Comfort, Think Alpen!

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AlpenHigh Performance Products

At Alpen we custom manufacture super-insulating, thermally-efficient residential and commercial windows and doors utilizing a unique proprietary combination of component products, including lightweight suspended-film technology and a fully insulated fiberglass framing system.  Our American-made product is custom manufactured by experienced craftspeople driven by the utmost attention to detail and only the highest quality materials.

Founded on a 30-year legacy of innovation in advanced fenestration technology design and manufacturing, Alpen’s windows today have  a measurable impact on energy efficiency and overall comfort, durability and style that is second to none.

With Alpen products, you can feel the difference.


Alpen High Performance Products (Alpen HPP) uses cutting-edge fiberglass framing systems to offer superior performance to conventional fenestration materials. Because fiberglass is incredibly durable, versatile, efficient and stable, it is the optimal material for super-insulating windows that provide lasting comfort and performance.

Benefits of fiberglass include:

  • Extreme corrosion resistance: fiberglass is the only framing material that particularly resists environmental damage caused by corrosive salt air or high temperatures.
  • Superior insulator even in extreme environments: dimensional stability even in extreme thermal cycling (heat, cold humidity), Alpen Windows fiberglass frames offer the aesthetic of classic wood clad windows but with better insulation.
  • High condensation resistance: the insulating nature of fiberglass prevents condensation and helps keep humidity within a proper range, this limits the growth of molds and mildew and helps keep your home’s interior air quality healthy.
  • Superior strength to weight ratios: Alpen Window’s fiberglass series are ideal for large window openings – they are 86% of the yield strength of aluminum and are pound-for-pound, stronger than aluminum.
  • Practically maintenance free: the inherent strength and nature to distribute impact loads even in sub-zero temperatures, fiberglass frames will not suffer the pockmarked surface damage that is common to wood and aluminum windows, and because fiberglass takes paint easily with excellent adhesion, you can change the color of your windows any time you like.
  • Very low coefficient of thermal expansion and contraction: stresses on seals, caulks and joints are minimized, contributing to higher efficiency windows and tight seals that are resistant to air leakage and water penetration.
  • High glass to frame ratio: the strength of our fiberglass frames means more of a viewing area because of the higher glass to frame ratio, compared to wood windows.