Architecture: The green nature of windows

In the third of a Catalyst Community series, we’ll learn about the green nature of windows.

Our instructor is Paul Haselhuhn, a Midland resident, and the president of WTA (Wigen Tincknell Associates) Architects, a general practice firm founded in Saginaw in 1947. They specialize in architectural design including commercial, education, healthcare, governmental and more. Haselhuhn has been with WTA since 1998. He’s been a project manager on a wide variety of projects and now specializes in higher education and commercial facilities. 

Catalyst Community: The Green Nature of Windows
Paul Haselhuhn, President of WTA Architects

The fact of the matter is we spend up to 90% of our lives indoors. Most of us, however, are driven to be outdoors. Whether we realize it or not, we physically and emotionally benefit from nature and the sun. It’s been said that the best place to find religion isn’t in a church building, but by taking a walk in the woods. Architect Alden B. Dow embraced this idea in not only his design of places of worship but in architecture as a whole. The element Dow often used in his designs to connect the interior with the exterior was glass.  

Paul Haselhuhn is the president of WTA Architects.Glazing, that transparent component of a building’s envelope, which connects our environments, is one of architecture’s most sustainable elements. It impacts energy usage, ventilation, and occupant health. In many ways, more so than any other sustainable feature a building can engage. 

Prior to the addition of mechanical and electrical systems, openings in the building’s envelope, whether infilled with glazing or not, were the primary source of light, ventilation, cooling, and even helped to heat a building’s interior. There was a time when architects used to take advantage of these features. But over the last century, with some exceptions, we have largely ignored the benefits of a building’s glazing. With the advent of electric lighting and HVAC systems, we’ve become accustomed to muscling the heating and cooling into a building, forcing fresh air in and contaminated air out, and artificially lighting the interior to make spaces usable.
The way we treated a building’s glazing became worse during the energy crisis of the ‘70s, when a lot of reactions by architects and building owners focused on glazing as the primary loss of energy in a building. And it was an easy target. 

Existing buildings, K-12 schools being a prime example, saw large expanses of single-pane glazing systems replaced with EIFS infills and small double-hung replacements. Many of those schools, when they were designed, used large amounts of glazing for light, ventilation, and connecting the occupants with the exterior. Additionally, new buildings were designed with a focus on more energy-efficient walls. While a positive step for architecture as a whole, since glazing technology was much further behind, in many cases the windows were a forgotten element.  It was a knee-jerk reaction; the fundamental building elements in architecture were changing and we were going through some growing pains.

First United Methodist ChurchIn recent years, Low-E technology has greatly improved, double-pane, argon-filled insulated glass has become the norm, and warm-edge spacer technology has thrust glazing efficiently forward to catch up with the remainder of the building envelope. Choosing a higher-performing glazing for a building, even though it may have a higher initial cost, can also have a quick payback, in some cases as little as just a couple of years.  Having said that, a building’s glazing is still its weakest point for energy loss.

Fortunately, many of today’s architects are returning to the principles of sustainable design they have used for centuries. No longer do we shy away from glazing, but we embrace it through understanding its added value to a building’s space, implementing time-tested principles of how to control solar gain and energy loss by how a building is oriented on its site, and through the use of properly designed overhangs, light shelves and sunshades.