Weathertight Pella Window Comparison

Styles

• Pella’s casement or awning style windows leak less air than sliding style, single- or double-hung windows do because their sashes press against the frames when they’re closed, according to Consumerreports.org. Both window styles also provide better ventilation. Awning-style windows are hinged at the top and open outward while casement windows are hinged at one side and usually open outward. Pella 350 Series casement or awning windows are available either as double- or triple-pane glass and contain argon gas between the layers of glass to provide additional insulation.

Glazing

• Double-glazed windows can cut heat loss almost in half. Triple-glazed windows provide even more insulation but are more expensive and weigh more. If you want the best weather-tight windows, choose tempered insulated or tinted insulating glass for Pella’s 350 Series casement or awning windows. The tinted insulating glass is available in gray, bronze or green, and blocks the sun so it keeps rooms cooler and reduces glare. Tempered insulating glass is safety glass.

Low-E Coating

• A low-E coating is a thin metallic film placed on your window to keep heat in your house during the winter and out of your house during summer. Pella’s low-E coating blocks 95 percent of the sun’s ultraviolet rays, according to the company's website. It’s optional in the Pella 350 series and is available without argon if you live in a moderate climate.

Frames

• Frame your Pella windows with wood or fiberglass. Wood frames insulate 1,800 times better than aluminum, and fiberglass composite material does just as well, according to Pella's website. In addition, both types of frames perform well when it comes to keeping out cold air and rain. Pella covers its wood frames with aluminum cladding so they don’t need to be painted.

Fixed Windows

• Pella’s fixed windows don’t open, so they’re airtight. Their purpose is to provide lighting, not ventilation. Fixed windows come with either double or triple insulated glass, and with fixed windows you have more glass options. In addition to tempered insulated or tinted insulating glass, you can select impact resistant insulating glass, laminated insulating glass or clear insulating glass.