Windows, like animals, have many different varieties and functions in contrasting ways. Two of the most paradoxical windows are sash windows and tilt turn windows. These two windows are prominent in the window world with very distinct details. Understanding these distinctions can serve as a guidepost while selecting the right window type for your home.
A sash window is a common North American window that is seen in many homes. Although these windows are most common in North America, they made their first appearance in European countries (like most of our architectural influence). A sash window is a framed window with one,or more panels, (aka. double-hung window) of glass with one or more movable panels. The top window panel is stationary with the bottom panel sliding up to rest on top of the top panel of glass. Many times, these windows are associated with historical building design with window muntins. Modern sash windows will often mimic their historical predecessor with faux muntins or window grilles applied to the outside of the glass. Due to its construction, the sash window generally has a lower thermal performance when compared to its adversary the tilt turn window. The movable lower sash adds an additional center frame, from the top panel of glass, that creates a thermal weak point and an air seal weak point that lowers energy efficiency.
A tilt turn window is predominately used in European countries and has just started to make an appearance state side. These windows are a single plane of glass surrounded by a 4-sided window frame. (Not to be confused with the number of panes of glass, which is typically double or triple pane.) Simply put, the tilt turn window is inward opening and functions in two ways. To open, the handle is turned 90 degrees with the hinge on the right or left and swings inward. To access the tilt function, close the window and turn the handle 180 degrees up, to activate the bottom hinges, allowing for the top portion of the window to vent at the top. The tilt turn window has sturdy hardware with multiple locking points that create a tight air seal. This creates less opportunity for air leaks, while still allowing for ample ventilation when operated in either form. Lastly, the tilt turn window is the ease of cleaning for the interior and exterior glass.
Although tilt turn windows are somewhat “new” to the American market, we believe decades from now they will be adopted as a “common North American window” much like its predecessor, the sash window.