It's time for a frank discussion about fenestration!
by Roger Faris
This is a good time for some clear thinking about the windows in our older homes. A window replacement project may be an opportunity to restore architectural integrity that has been the victim of past remuddling projects. Other goals might be to save on heating and cooling expenses, or to preserve our planet for future generations. Since there are many factors to be considered and choices to be made, you'd better keep on reading.
Let's begin with esthetics. In an Atlantic Monthly magazine article (Sept. 1996), architectural critic James Kunstler encourages us to pay more attention to how our houses look from the street. He discusses harmonious proportions of windows and uses illustrations to show various principles of pleasing design. He argues, for example, that horizontal windows tend to "subvert the dignity of the standing human figure." Part of Kunstler's thesis is that the civic life of our communities is degraded when our homes look like television sets.
In earlier decades most people chose replacement windows which were energy wasting steel or aluminum framed single-glazed units. They were often quite unattractive. It was common for the original double-hung, multi-pane wood windows to be discarded in favor of huge picture windows, and window trim was usually eliminated in the "updating" project. The trend is now toward installing windows which complement the original architecture. Fortunately, beautiful and efficient products are now available.
The sashes and frames of high performance windows are made with wood, vinyl, or a combination of materials. Modern aluminum or steel units incorporate wood, plastic or foam thermal breaks to prevent heat loss and condensation problems. They can all be ordered as single or double-hung, casement, awning, slider, picture window style, bow, bay, transom, circle tops, ovals, octagons, or any imaginable custom shape.
Part of the energy efficiency of new windows is achieved by having multiple layers of glass or plastic, separated by dead air spaces. Sometimes the spaces between panes are filled with argon or krypton gas to further slow the transfer of heat through the unit. Many customers ask their window dealers if krypton gas is bad for Superman. They are assured that it's only green kryptonite that can harm the man of steel.
Another feature of advanced window design is a special low-emissivity coating which is applied to the glass. This further reduces heat losses in winter and heat gain in summer. The Low-e coatings also protect interior furnishings from being damaged by sunlight.
An additional factor in energy efficient window design is the elimination of drafts or leaks. This is accomplished with high quality sash and frame materials which won't warp, and with well designed weatherstripping and hardware. The U - factor is a number which provides us with an overall energy efficiency rating of a window unit. This system based on the standards and research of the National Fenestration Rating Council. A lower U-factor number indicates a more efficient window. According to Kris Sandra, the Commissioner of the Minnesota Department of Public Service, people who live in cold climates should look for a rating of .35 or less.
There is, of course, room for alternative opinions and approaches to this subject. Years ago, window expert Terrence Meany introduced an intriguing technical term, the "Hawaii factor." His analysis suggested that we might consider repairing and weatherstripping our old windows rather than investing in replacement. The savings are then used to travel to a tropical climate during January or February. The furnace thermostat may be turned way down in our absence.
Putting aside the lure of Hawaii, there are good reasons for all of us to cut back our energy use to a greater extent than we achieve by repair of drafty windows. Each day we Americans allow an enormous amount of energy to escape into the environment. Much of it has been produced by burning oil, gas, and coal. If we use less fossil fuel for heating, cooling, and other activities, we'll release fewer tons of sulfur dioxide, nitrous oxide and carbon dioxide into the air. This really is part of preserving our planet.
In this spirit of doing more good, here's a great idea: I'll forgo the purchase of a high performance car so that I can invest in high performance windows. This resource conserving choice saves two kinds of gas and improve the domestic economy. My plan also includes annual visits to Maui. Janet will like this. Our anniversary is in February!
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