The history of and the traditional useful purpose of double hung windows has gotten somewhat obscured over the years. So much so that many people who have these traditional type windows know very little about their origins or to what purpose they were designed.
The usually large double sash windows date back to the late 17th century in Europe, where they were first used usually in wealthy aristocratic homes of the time, or even in stately manners and castles. The people of the time liked having large ornate windows. The larger the windows one could afford carried with it some significance. It was akin to hanging out a sign telling the world about the wealth or status of the person who lived in the residence where they were installed.
The problem with homes of the time was that during the summer months, homes tended to be very warm, even to the point of being intolerably hot. It is thought that the first double hung’s were used around 1670 to 1690.
By virtue of the surge in the study of the sciences the era saw the concept of the double hung window was born. Someone who understood the workings of thermodynamics applied the principle to window design thus producing the first manner by which indoor air was regulated.
The principle of thermodynamics is simple really. Hot air rises, and cold or cooler air falls or sinks to the lowest level within a confined space. This simple principle along with double hung windows afforded homeowners of the time a moderately effective way to regulate the temperature inside the home.
Because hot air continues to rise when uncontained, opening the upper sash of the double hung window allows an escape point for the warmer air. As the warmer air escapes from the top of the window, its volume is replaced by cooler denser air flowing in through the open lower sash.
Homeowners learned the art of temperature regulation using the double hung window and the principle of thermodynamics to bring about what is revered today as poor man’s air conditioning. Today few people who have double hung windows know the art of temperature regulations using them.
So in answer to the original question, do double hung windows serve a purpose or have any advantage over other types of windows? The answer is a resounding yes. In fact if people would learn again how to regulate home temperature using windows they may already have, I am sure they would be moderately surprised how much money they could save on the electric bill. Not to mention how much stress they could take off the environment by using this little known green trick that helps keep the home cooler in the summer.