On days when the mercury hits 90 degrees and keeps rising, it’s almost instinctive to reach for the HVAC control. Most folks in the US, especially in warm, humid states, can’t imagine life without their air conditioning. But A/C has only been in use in private houses for the past 80 years. How did human beings beat the heat before then, and what can this teach us about environmentally friendly cooling for our homes today?
The earliest method of keeping cool was making use of the earth itself. The area beneath the surface of the soil or rock is not affected by seasonal weather patterns, so sheltering in an underground cave or a grotto hewn from a mountainside provided welcome relief from the heat. Interestingly, when today’s architects use this age-old idea to design energy-saving underground homes, it is considered cutting edge technology.
Construction of thick walls from materials such as adobe and stone also kept indoor temperatures relatively stable through their insulating effect. We can use this idea in our homes today by adding insulation and weather-stripping, especially in the location most exposed to the sun – the attic.
The ancient Romans are famous for their intricate system of aqueducts, which supplied drinking water and carried away waste. These brilliant engineers also built aqueducts between the double walls of their homes to harness the cooling power of water. Roman emperors were treated to the coldest form of water – snow – which was brought to their palaces from mountain peaks.
Hanging damp mats or sheets is an old-fashioned way of chilling rooms via evaporation, and evaporative cooling caught on in a big way in the 19th century. Today’s desert coolers use the same principle of evaporation to provide an energy-efficient way to lower your home’s temperature.
Wind towers were constructed by the ancient Persians to circulate the air and reduce the temperature in their dwellings, as a prelude to today’s fans. Automated home fans first appeared in the mid-19th century, driven by water. Two hundred years later, electric ceiling fans are an energy-smart supplement to air conditioning.
North American homes of an earlier era were designed keeping in mind the principle that hot air rises. The high ceilings (9 feet or more), which were once the norm, conducted smoky air from cooking and heating fires upward, together with the hot air of summer. Multi-story houses were frequently built with an open stairwell to pull heat toward the roof. Builders sometimes even crowned homes with a turret to vent heat comfortably outside.
Although it’s not practical to raise the roof of a more modern dwelling, you can still use another time-honored, low-tech notion about cooling with air currents. Open windows on opposite or adjacent walls at night to provide cross ventilation.
The cooling power of plants was recognized by the Mughals of India, who planted roof gardens atop their homes almost two millennia ago. Both the greenery and the layer of earth underneath acted to absorb the rays of the sun.
Trees, vines and plantings around a home not only provide shade from strong sun rays; planned carefully, they can also be used to direct breezes. Even your lawn helps lower the heat in your home by as much as 10 percent.
Blocking the Elements
Houses of old were designed with built-in options to shield them from the elements. White or other light exterior color, especially on the roof, acted to reflect the sun’s rays. Awnings, shutters and other types of window shades could be used to block the sun on hot summer days. While these are all still useful, window films or glazing can permit you to have both light and relief from the sun.
The “summer kitchen” is a great American tradition. Moving your household’s cooking – and the heat that results – outdoors in hot weather is a sound common-sense move.
Another way of keeping cool (or, more accurately, sleeping cool) that you may remember fondly from your childhood is bunking out in the shade of a gracious porch, preferably a screened one. The screen lets the cool night breezes in while keeping nighttime pests like mosquitoes out.
Modern landscape architects expand upon this clever idea by designing garden areas as attractive outdoor rooms.
Laura Firszt writes for Networx.com