Like many products for our homes, windows just aren't what they used to be. In this case, that's a good thing. Certainly their principal function -- providing access to fresh air and natural light -- remains the same, but the refined materials and improved details in today's versions put a lot more control at your fingertips. Not only can you get a wider variety of standard shapes, sizes, and designs, but the product also is more likely to be engineered for performance levels that older windows just can't match.
"The thing I always tell people is that they need to start looking at their windows rather than through them," says Alan Campbell, president of the Window and Door Manufacturers Association. "With all the developments in technology and materials, they're literally appliances in the wall."
Granted, you can't open a window and pull out, say, a chilled bottle of juice or a hot pan of freshly baked bread, but Campbell's point is that windows are no longer the passive light-bearers of yesterday. Today, they boast efficient designs and materials to keep wind and water outside where they belong and let the best of the sun shine through.
Before you start navigating through descriptions of argon-gas-filled glazing, vinyl-clad composite frames, and low-E coatings (those terms will be explained shortly), you need to grasp the basics of window types, components, and applications. As with most building material and component choices, successfully bending or breaking the rules first requires a grasp of the proven principles. For starters, here's a look at five common window categories:
Double-hung and single-hung -- This traditional design is still the most common for new construction and for remodeling. Double-hung windows feature a pair of movable sash that slide vertically within the window frame; single-hung models also feature an upper and lower sash, but only the lower sash is operative. (Because production volume typically is lower than for double-hungs, single-hung windows usually offer little or no cost advantage.)
Older versions of either type kept the windows open by means of cords, pulleys, and counterweights, but nowadays, tensioned spring systems perform that function. Appropriate for all but the most cutting-edge contemporary home designs, double-hung and single-hung windows can be found on traditional Cape Cods and colonials, multistory Victorians, early-20th-century bungalows, and other "period" architectural styles. Muntin and grille designs provide strong stylistic cues, but the basic design remains versatile.
Casement -- Casement windows pivot on hinges, somewhat like doors do, but they usually swing outward and are controlled by a hand-crank mechanism affixed to the windowsill. Casement shapes tend toward the tall and narrow, so wide wall openings usually feature multiples, sometimes with a fixed picture window in the center. Ventilation is generous relative to overall window area, because the entire sash swings open, but exposure of the outward-swinging frame can be a problem if rain arrives suddenly.
Ranch-style, Prairie-style, and other 20th-century home designs often feature this type of window. Grilles will help create a more traditional look, while an unbroken expanse of glass provides a contemporary flavor. Bedroom installations can be problematic, as many casements don't meet code requirements for egress windows, which must provide passage in the event of fire.
Awning -- This is another type of hinged window, but one that pivots at the top. With their horizontal rather than vertical orientation, awnings don't open as fully as casements, but they offer the advantage of shedding water harmlessly if left open during a rainfall.
Though they can be used alone, they're often installed above or below large picture windows to provide ventilation at the top or bottom of a wall.
Like casements, awning windows take on a more traditional flavor when fitted with muntins, but look contemporary when unadorned. They also face some of the same limitations in meeting egress code requirements if intended for use as bedroom windows.
Gliding -- The principle of a gliding window, where one or two sash slide horizontally in the tracks of the window frame, has a long history that includes Japanese shoji and other long-established uses. Still, the modern-day gliding window doesn't lend itself to such traditional designs as Cape Cod or Victorian-style homes. Like awning windows, gliders typically have a strong horizontal orientation, so they often work best with home designs such as ranches or Prairie-style buildings that have strong horizontal lines.
Picture -- They don't get any simpler than this. Picture windows are stationary (inoperative) windows used for light and views only. They don't have to be large, but often are. When maximum views are the objective, this type of window offers the least obstruction. Ventilation requirements are often handled by installing operative windows above, below, or alongside a picture window.
Like other window types, picture windows impart a decidedly modern feel when they're large and uninterrupted by muntins or grilles. Smaller sizes with grilles and appropriate trim can mimic most traditional looks.
Just about anything outside of these five basic categories qualifies as a specialty window. This term refers mostly to unusual shapes, such as triangular, round, half-round, and other nonstandard configurations. Most are fixed-sash (inoperative) and are included to create architectural interest.
On large "estate" homes, round, half-round, and other specialty windows can complement a traditional style. On smaller residences, which historically have featured simpler window shapes, specialty windows are more appropriate to contemporary designs. Keep in mind that for hundreds of years glass was handmade, scarce, and expensive, so the home styles that evolved during those centuries have characteristic looks: less overall window area and small panes of glass connected with wooden frameworks. Some specialty windows, especially large or oddly shaped ones, create a trendy look that may clash with the otherwise traditional exterior of some older homes.
Other specialty windows include bow and bay windows, preassembled groupings that actually change the profile of an exterior wall. Though substantially more costly than standard windows, these variations provide more light and ventilation in a given amount of wall area; create a more spacious feel and room for sill shelves, window seats, and other features; and add a lot of charm besides.
If you're remodeling an existing space, the choices for appropriate window types will often be limited and simple. For the most part, it's safer to stick with the predominant window type used in the rest of the house. Swapping window types or styles creates a patchwork look on a home's exterior. If the project is an addition that warrants a different treatment -- a breakfast room, for example -- repeat muntin styles or other details for consistency.
Incidentally, most muntin and grille options do a good job of mimicking the look of a true divided-light window, in which small individual panes of glass are separated by the muntin framework. Snap-on grilles are the most affordable option. They attach to the inside and/or outside of the sash and can be removed easily to clean the glass. Simulated divided-light windows feature both of these surface-mounted grilles and also have a matching grid sandwiched between the panes of glass for a more authentic look.
Whatever style you choose, keep in mind that conventional windows install the same way for remodeling or for new construction; be prepared to remove and reinstall the window casings and trim if you're remodeling existing space. If you want to avoid that work but still get the improved looks and energy efficiency of a newer unit, shop for replacement windows. This special category of window is custom-made to the required size and designed to install in existing frames without modifying the wall opening or disturbing the finish trim.
All this talk about traditional and proven window types and styles may have you wondering what new windows have to offer your remodeling project. The answer is materials technology. Today's windows offer traditional appeal with big improvements in energy efficiency, maintenance requirements, and other performance-related features. Some of these upgrades come in the form of glazing; some in the form of frame components.
With a few exceptions for Southern geographic regions and economy-grade product lines, virtually any good-quality window manufactured today gets fitted with insulated glass. This means the glazing is actually a sandwich of two panes of glass separated by "warm channel" spacers. The spacers act as thermal breaks to keep the exchange of inside and outside temperatures to a minimum, and the voids between the panes are sometimes filled with argon gas, which offers better insulating properties than ordinary air. Unless you're ordering custom windows to get a certain size or look, the standard units you buy will likely be dual-glazed, argon-filled, and perhaps have a low-E coating (for low emissivity, which inhibits the transfer of radiant solar heat) on the glass.
For unusual conditions or requirements, you can custom-order windows with triple-glazing (a three-pane sandwich), high-performance coatings to block ultraviolet light and solar heat gain, or tempered-glass panes. Tempered glass is required by code for certain applications, such as glass doors and some window installations with low sill height. For more extreme conditions, such as coastal environments, consider laminated impact-resistant glass designed to withstand hurricane-force winds and the impact of airborne debris.
Of course, the frame components that secure the glazing give the window its structure and its operation. Wood has been, by far, the traditional and most common material for the jambs, sash frames, sill, and trim, but maintenance requirements and the inevitable problems with water and sun damage have brought changes to that status. Protecting wood with a weatherproof covering called cladding eliminates the need for painting and protects the window from the elements. When you go window shopping, you'll find two common approaches: vinyl or aluminum.
Vinyl cladding offers the advantages of excellent impact resistance and integral color, so scratches on the surface won't expose the layer underneath. You have to accept a limited number of color choices from most manufacturers, though -- often white, a dark taupe or neutral brown, and a lighter neutral (beige) color.
Aluminum cladding requires more care in handling to avoid scratches or dents, but the factory-applied paint finishes are extremely durable and typically come in at least a dozen colors.
Either way, you lose the flexibility of changing the color later and keeping the same low-maintenance feature. The interior surfaces of these windows are typically finish-grade wood that can be stained or painted. Clad-wood windows account for the largest share (about 90 percent) of the wood-frame window market, though wood windows with primed or raw exteriors are still available from several makers.
Recently, wood composites (a mix of shredded wood fiber and plastic resins) have become more common for the structural core of window frames and components. These compounds are extruded into hollow tube shapes, then covered with vinyl or aluminum exterior cladding and a paint primer or vinyl cladding on the interior. This approach capitalizes on the strength and insulating properties of wood but doesn't require the expensive high-grade materials used in solid-wood frames, providing a cost savings -- but you can't use a transparent stain on interior surfaces.
Some window manufacturers do without wood entirely, opting instead for frame components made of aluminum or solid vinyl. Though less expensive, these choices have drawbacks, too. Aluminum, like any metal, makes a poor insulator. Temperature differences are readily conducted between the inside and outside of the window, resulting in energy losses and related problems, such as condensation. Southern regions of the United States, especially the desert Southwest, still see widespread use of aluminum-frame windows, but colder regions call for something with better insulating properties. (Windows for commercial installations are an exception.)
Vinyl lacks the structural rigidity of either wood or aluminum, so the frames flex more and also move in response to swings in temperature. Some manufacturers use steel inserts to add strength and stiffness to the frames -- a feature you can ask about. According to the Window and Door Manufacturers Association, solid-vinyl double-hung windows represent the fastest-growing segment of the residential window market, but other factors -- your home's age, window type, and color scheme, for example -- will determine whether this is the best choice.
Of course, the options and improvements in new-generation windows affect the cost, but like most choices about how to improve your home, these decisions should be weighed in relation to long-term benefits. Except for sash kits and replacement windows that don't require removal of the old frame and trim, installation costs for a given window will vary little if at all. What's more, differences in the up-front purchase price may eventually be offset by other factors: energy efficiency, overall quality, and required maintenance.
Aside from normal variations in retail pricing, two other factors can affect what you pay for windows of a given size and quality. First, try to work with standard sizes from a manufacturer. Prices for custom-size windows can easily double just to give you a variation of an inch or two in either direction; usually it's cheaper to modify the rough opening in the wall than to purchase custom goods. Besides, odds are if you're removing a window, it was a stock manufactured size and shouldn't be hard to replace with another. Second, see if you can work with what the retailer stocks. When asked about the vinyl-clad wood window, one home center also offered to special-order a "cheaper" nontilting version from the same manufacturer. But because the tilting version was stock inventory, it actually cost $15 less than the nontilting model.
Whatever your stylistic or performance priorities, don't overlook the details that make windows easier to live with. Be especially attentive to features that make cleaning the glass easier. Many double-hung windows now come with tilting sash so both interior and exterior glass surfaces can be cleaned from inside the house -- an especially welcome feature on second-story windows. See also that the grilles snap on and off readily without tools.
Some manufacturers offer improved hardware for crank-out windows such as casements and awnings -- specifically, collapsible or low-profile handles that don't interfere with blinds or other window coverings. Others offer a variety of style options for latches and locks. To be safe, ask about these and any other convenience features before the units end up in your walls.
Once you know the terminology and the quality cues to look for when window shopping, it all comes down to five basic decisions:
1) Determine the window type: double-hung, casement, awning, gliding, picture, or specialty.
2) Specify the materials: solid wood, vinyl- or aluminum-clad wood, solid vinyl, or aluminum.
3) Know the glazing: insulated glass, with argon gas and low-E coating if desired; tempered glass where code or safety considerations warrant.
4) Decide the details: Color, grille, and trim choices should work with your home's style.
5) Size it up: Work with standard sizes if possible. Most come in increments of 2 or 4 inches, so there's often no need to order custom.
If you're working with an architect, designer, or contractor, he or she should guide you through the choices that will work best for your project, but spell out the features you want. Odds are you'll be living with your choices for a long time, so don't be shy about making your preferences known.