How Homes Kept Cool Before AC
The end of June is the time of year when we start to appreciate our air conditioner again, with summer’s soaring temperatures and unbearable humidity just around the corner. Today, over 80% of American households have AC units to provide comfort at the flip of a switch, and has grown from a luxury to a necessary part of the quality of life in the industrialized world.
But, while some of us might wonder how our grandparents survived hot and steamy summers, the fact is that those older homes had a few tricks up their sleeves. The architecture of these buildings was designed and built with features to help the homeowners stay as cool and comfortable as possible.
Ceilings between 10 and 14 feet were common in older homes for more than just a grand appearance. As heat rose to the ceiling, lower areas stayed cool and comfortable. Ceiling fans – powered by electricity or elaborate rope systems – facilitated air movement to create the perception of cooler temperatures.
In northern states, it was common to create a stack effect, by opening windows in the basement and top floor, generating a cool breeze through the home. As you traveled south, you would see homes built on blocks to allow breezes to flow underneath to cool the house.
Many historic homes feature large, double-hung windows. Opening the top sash during the day allowed hot air to escape, while opening the bottom at night would allow cool air to flow inside. Additionally, thick, long curtains were used to “draw the drapes” and keep out the heat without sacrificing light.
A transom –a small window over a door – allowed warmer air at the ceiling to circulate up to higher floors, providing much needed air movement throughout the house. Transoms were installed over both interior and exterior doors, with the later including hinges and special hardware for security.
Wrap-around porches used to be a staple of southern homes for a reason. These porches offered shade from the direct sun while allowing light to pour through windows. Screened and furnished sleeping porches were also common to catch a cool breeze on a summer night…without all the bugs.
Many older homes had light-colored or silver-metal roofs made of lead, tin or copper to reflect heat away from the home. Quite the contrast from today’s dark asphalt shingles that can absorb the sun’s rays.
For more expensive homes, thick brick masonry and stone walls were a great insulator against winter cold and summer heat. Walls 12 to 24 inches thick were common in the Deep South.
Looking at a historic home yourself?
If you own or are considering buying a house built before the age of common air conditioning, you may have the potential for energy savings due to some of the above architecture elements. Consult both an architect and an HVAC professional, like BNG, to determine the best way to preserve the ‘look’ of an older home using modern, energy-efficient materials.