Photo-illustration: Mark Hooper
Illustration: Gregory Nemec
Illustration: Gregory Nemec
Illustration Gregory Nemec
Illustration: Gregory Nemec
Illustration: Gregory Nemec
Illustration: Gregory Nemec
Double-hung windows are the most popular. Modern versions have a tilt-in sash for easy cleaning of the outside panes. These all-around favorites have some limitations; for example, they're not the best choice in locations where you have to stretch to open them, such as over a kitchen sink.
Casement windows are hinged at the side and typically swing out. The full-height opening provides excellent ventilation. But casements, especially those made of wood, can suffer damage if left open in the rain. They're a poor choice where they would open onto patios or other traffic areas.
Sliding windows function like double-hungs turned sideways. They look best in contemporary homes, and work well opening onto a deck or exterior stairway, where a casement's swing would cause trouble.
Awning windows are hinged on the top and open out from the bottom. They're often used for ventilation under large, fixed-pane picture windows in contemporary-style homes. They keep out rain even when open, as long as the wind isn't blowing too hard.
Hopper windows are like awnings in reverse: They're hinged on the bottom and swing in. Hoppers are typically used in basements or high up on a wall over a large, fixed-pane window.
Fixed windows don't swing, tilt, or glide; the sash is permanently fixed to a frame. Often flanked by double-hungs or casements, or set above or below an awning or hopper, fixed sash come in a variety of shapes, including round, half-round, diamond, and trapezoid (to echo gable-end rafter pitches.)