French casement windows: efficient and elegant design

Most residential casement windows are rectangular, open outward and are hinged on one side, allowing you to direct the flow of fresh air into your home. Usually they are configured as twins and triplets (two and three windows joined together). Twin casements tend to open from the center with hinges on the frame section of the window, while triple configurations generally have a fixed, non-operable center window with a hinged window on each side. Some configurations allow you to open each unit.

Not all casement windows, however, are rectangular, two-sash casements--some have curved tops. Both sash open from the middle, with the curved section turning toward the center. These elegant windows are referred to as French casements. Historically, true French casements have no middle post which can obstruct views. Typically, French casements open inward. Most casement windows in the United States have the mid-post for locking and joining two windows to form the twin unit.

Shape and design

All French casement windows have arched tops, though other details of the design vary. Pella offers an inward-swing French casement:

credit: Pella

Windows in the United States, however, normally open outward. There are many other top shapes available. Parrett Windows, a specialty window manufacturer of higher-priced, quality products, offers five different French casement shapes:

credit: Parrett

Installing a new window with a different fit

Window manufacturers making French casements include Andersen, Marvin and Jeld-Wen. These are not inexpensive products. Bending wood is difficult and requires many hours of labor--and the prices reflect that time. Expect to pay between $2,500 and $3,500 for a good-quality pair of French casements.

Installation costs may also be higher, especially in replacement situations. If a square window is being replaced, even one of the same width and height, the opening must be modified to accommodate the curved tops of the new windows. Installation costs may be as much as 50 percent higher.

Available materials include wood, wood clad with aluminum, vinyl cladding and vinyl windows. Parrett windows are available in 15 wood species including the usual pine, but also alder, mahogany and hickory. Marvin and Jeld-Wen's products are clad with aluminum. If you plan on remodeling a living room, kitchen or bathroom, consider adding an elegant design element -- a French casement.