Even in these days of belt tightening, installing replacement windows remains a virtual mania among homeowners. Take a walk through any suburb built before 1980, and you may find that half the houses no longer have their original windows. Alas, the usual replacements — extruded PVC or "vinyl" windows — are dismayingly easy to spot, what with their wavy, cellophane-like glass and glaring white plastic frames.
Considering the impact window replacement can have on your home’s appearance, it shouldn’t be taken lightly. To wit: The last big window-replacement fad happened during the 1960s, when that era’s perceived "modern" upgrade — sliding aluminum windows — were retrofitted to countless traditional homes, from Victorians to bungalows. The aesthetic fallout from this campaign is still painfully obvious in many old neighborhoods.
In retrospect, of course, aluminum sliders installed in a traditional home are rightly seen as a glaring anachronism, and frequently bring a penalty in resale value over homes with their original windows.
Today, thanks to the same kind of offhand, insensitive and often just plain unnecessary ways in which vinyl windows are installed in older homes of all eras, they’ve essentially become the modern-day version of the aluminum slider. And with a little historic distance, the aesthetic results will be just as regrettable.
Window replacement is often cannily advertised as a great energy-saving investment, which is probably why so many well-intentioned homeowners choose this route. And it’s true enough that switching from single-glazed windows to double-glazed ones will save roughly half the energy lost through the glass. But here’s the catch: In the average house, windows typically make up a relatively small fraction of the total heat loss. Hence, dollar for dollar, there are far more cost-effective ways to improve your home’s energy efficiency.
Upgrading attic insulation ranks first among them, since ceilings are typically the single greatest source of heat loss. The current standard for attic insulation is R-30; so if your house has appreciably less than this, adding insulation will be far more cost effective than replacing your windows.
The same holds true if your furnace and ductwork predate 1980 or so. Modern furnaces now have thermal efficiencies in the neighborhood of 95 percent, versus typically dismal efficiencies in the 70s and even down into the 50s for some older gravity furnaces). Because a furnace upgrade addresses the root of inefficiency rather than just nipping at the leaves, the resulting energy savings can be truly dramatic.
One more thing to consider: Aside from offering double glazing, there’s very little that’s green about vinyl windows. Vinyl is, of course, the plastics industry’s more euphonious name for polyvinyl chloride, which a number of environmental authorities consider to be the most toxic plastic in the environment. Bury it in a landfill, and it just sits there. Burn it, and it produces dioxin, a toxic chemical compound that’s a known teratogen, mutagen and carcinogen.
The bottom line? Think twice about replacing your current windows with vinyl ones for energy-efficiency reasons alone. Chances are you’ll get more bang for your energy buck with simpler upgrades that don’t even show on the outside.