Double Hung Window

A type of sliding window that allows the homeowner to open either the upper or lower portion (or sashes) while keeping the other sash closed or open. Double hung refers to the window's open and close mechanism. Some double hung windows can slide as well as tilt to allow for more natural cleaning and airflow.

Double hung, and other sliding windows are generally less energy-efficient than casement windows, and for that cost typically less.

Double hung windows are standard as a replacement window in North America due to their cost. The tide is changing as energy efficiency is becoming a priority for many homeowners.

As a sliding window, double hung windows tend to leak more air and be less energy efficient than other types of windows. More sustainable choices are fixed and casement windows - the latter offer more durable and tighter seals thanks to compression type gaskets.

While double hung and other sliding windows can obtain Energy Star Certification, this certification should be a minimum when window shopping, and not an indicator of top performance. Passive House grade windows are regarded as top-performing windows. They utilize multiple seals, gaskets, and open and close mechanisms that minimize air leakage and provide better insulating properties.

The most basic window is, of course, merely a hole in the wall to let in light and air. Many different materials have been used over the centuries to fill window openings to let in light while keeping out insects, animals, rain, and wind. Before glass became widely manufactured, translucent materials including paper, animal hides, flattened animal horn, and even thin slices of marble were used as window panes.