By Sean O’Keefe
Those who have made the science of design and construction their life’s work know that there are levels to this game. Indeed, in most fields, goods, services and products can be generally understood in terms of Good / Better / Best, with commensurate expectations tied to cost, quality and availability associated with each classification. In the custom residential design and construction market, where the options are virtually limitless, the certainty that one choice is unequivocally better than all others would be difficult to quantify. For those involved in the design and construction of passive houses, the choice is simple.
“There are five attributes of a passive house – super-insulated, airtight construction, thermal-bridge-free design, heat recovery ventilation, and high-performance glazing,” says Craig Maierhofer, Vice President of Business Development at Alpen High-Performance Products. “The home’s window and door openings are critical components in the passive house’s overall performance. That goes for where the designer puts them to let light in and how well they perform as part of the super-insulated building envelope to retain heat during cold months.”
“The idea behind Passive House Design is to make the house so airtight that you could heat it with a hair dryer. The other key piece is the ERV or Energy Recovery Ventilation, which involves recovering the heat from the air while continuously bringing in fresh air from outside.”
After more than 14 years in metal processing and distribution, Maierhofer was looking for work he could put his heart into when Brad Begin, Alpen’s CEO, invited him to join him in pursuit of the world’s best windows.
“Before coming to Alpen, I was involved in different areas of clean and alternative energy. I wanted to pursue this passion, and when I started learning more about passive house design, I saw an amazing opportunity with Alpen,” says Maierhofer from Alpen’s manufacturing facility in Louisville, Colorado. “We desire to make the world’s highest-performing window, so naturally Passive House Design buildings, both residential and commercial, make up about two-thirds of our projects.”
Fundamentally, where thermal comfort and glazing intersect is in the changing of the seasons. In the summer, shades above windows keep solar gains out. In the winter, the sun’s lower position in the sky allows light in. High-performance windows allow solar gains to warm a passive house by trapping heat energy for reuse.
“The idea behind Passive House Design is to make the house so airtight that you could heat it with a hair dryer,” continues Maierhofer. “The other key piece is the ERV or Energy Recovery Ventilation, which involves recovering the heat from the air while continuously bringing in fresh air from outside.”
The centerpiece of the puzzle is the thermal-bridge-free design and detailing. In the walls, this means sealing critical joints by using specific wall assemblies that provide a continuous thermal barrier. In the windows, this means better everything.
Alpen’s Tyrol Series windows are triple- or quad-pane, internally insulated glazing units that come in both fixed and operable and can be configured for three levels of solar gain – balanced for typical climates, solar control for hot climates, and high-gain for cold climates. The Tyrol PH + window provides Alpen’s highest-rated frame insulation combination, used to meet Passive House Design, net-zero energy, or other high-performance objectives. Tyrol Series windows are certified by the National Fenestration Rating Council up to R-11.
“Our windows allow air to pass through at less than 0.01 cubic feet per minute, or virtually not at all,” says Maierhofer. “In addition to being triple or even quad pane, the big difference is the air pocket size between panes. The consumer-grade, double-pane window typically has an overall width of 5/8th or 3/4th of an inch thick. Our windows are one and 3/8th inch standard. We can go out to two inches. The wider glass pocket helps with insulation and sound attenuation – a wonderful benefit of passive homes – they are super quiet.”
Now nearing ten years at Alpen, though Maierhofer is no longer new to high-performance windows and doors, the company he works for has been at it a lot longer.
“Alpen is unique in its approach because, from 1981, when the company was founded, until 2006, Alpen only made insulated glass units or IGUs. Alpen made the IGUs for other companies that used them in framing options they developed on their own,” says Maierhofer of Alpen’s first 25 years as a business. “Today, Aplen has been developing and improving our in-house framing system for nearly 20 years. We also sourced German-engineered hardware and designed the foam insulation to strategically fill the gaps. All of this results in a super high-performance window.”
Alpen’s Zenith Series windows and doors also come in three and four panes of glass in long-strand pultruded fiberglass frames that do not expand or contract with changing temperatures. Super-insulating closed-cell foam in frame and sash cavities provides maximum thermal insulation and condensation resistance. Profile heights of just two and 7/8th inch give an elegant, modern appeal while optimizing views and daylight. The high-performance water-based paint system is low VOC, environmentally friendly, and can be customized to any color or style. Three layers of weather seals and a multi-point locking system combine to create compression seals that reliably block air and water infiltration.
“Beyond performance, innovation is what defines Alpen,” says Maierhofer. “Inside our windows, the third and fourth pieces of glass are so thin they are virtually weightless. This thin-glass technology makes these windows weigh the same as conventional double pane windows despite being significantly wider.”
Every Alpen window or door is manufactured in Alpen’s Louisville, CO plant. Maierhofer shares that getting Alpen’s high-performance windows to customers nationwide is not without complications, however.
“When we manufacture the IGUs, we hermetically seal them to trap gases, which happens a mile above sea level. Since we ship everywhere, our packaging system must maintain the Argon or Krypton gas trapped within that seal as the window goes either up or down in elevation,” says Maierhofer. “Our packing includes a mylar balloon that allows that gas pocket to breathe as the product changes elevations. There is a balloon removal process when the windows and doors arrive at their destination. Installation should be done to American Architectural Manufacturers Association standards.”
Maierhofer points out that in addition to being high-performance within a home, Alpen’s windows and doors are equally beneficial in having a low environmental impact.
“Alpen’s manufacturing processes have focused on low-embodied carbon since the start. Those third and fourth panes inside our windows are made of super thin glass,” says Maierhofer. “The energy used to make thin glass is significantly less than thick glass because we get five times the coverage area in the finished product.”
Asked what he’d want you to know from reading this, Maierhofer is sincere. “Homeowners, designers, and builders don’t have to go to Europe to get high-performance windows suited for Passive Housse Design. Alpen makes them right here in the U.S.A. The effects of global warming are upon us, and people are becoming passionate about changing how they live to do something about it. The winds of change are here.”
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