Cool Your House Naturally
By Linda Mason Hunter
(Originally published in FiftySomething, publication of The Des Moines Register, June 2009)
© 2009, Linda Mason Hunter

This summer think twice about how you keep cool. Air conditioning is expensive, uses valuable energy, and puts carbon into the atmosphere which increases global warming.        

Surprisingly, the movement of air over the skin is the key to keeping the body cool. When it’s not sweltering hot outside, beat the heat by opening windows and running fans. These low-tech solutions cost less and are more environmentally sustainable. Make it your goal to walk softly, leaving as small a footprint as possible.

• Use cross ventilation. Cross ventilation not only cools the house, it bathes indoor air cleansing it of volatile organic compounds (VOCs), mold spores, and other pollutants offgassing from household products and furnishings. The key to cross ventilation is to open windows (or vents) on opposite sides of the house, especially in early mornings and late evenings when temperatures outdoors are pleasant. First figure out which direction the breeze is blowing outside (even if it’s minimal) then open windows on the windward side (where the air is coming in) and on the opposite (or leeward) side. This creates a negative pressure zone as air moves through the interior, causing more air to exhaust through leeward windows and drawing fresh air through the house.  

• Close draperies and blinds. Remember to shut windows when you leave for the day to keep cooler air inside the house and hot summer air outside. Keep blinds shut and curtains drawn, too, as sunlight pouring into the house only creates more heat. Keep lights off as they create heat.

• Use electric fans. If the breeze alone isn’t enough, set up a fan or two. Whether it is a $30 portable fan or a ceiling unit, fans use 90% less energy than air conditioning and make rooms feel seven to ten degrees cooler because of the process of evaporation, according to The Daily Green.

• Create a “wind tunnel” by placing one fan facing into the house next to the window on the windward side (where fresh air is coming in), and another fan at an opposite window positioned to blow warm air out. This strategy can be especially effective at night when temps are cooler.

• Install a ceiling fan. Ceiling fans do a good job of circulating air in rooms you occupy most, like the bedroom. Though you pay for installation, they use about 1/30th of the electricity of a room air conditioner. Energy Star-rated fans are 50% more efficient than conventional models and will save $15 to $20 a year on utility bills, according to the U.S. Environmental Protection Agency. Most can be run in reverse in wintertime, pushing warm air down from high spaces to help warm the house.  Don’t forget to turn fans off when you aren’t using them.

• Make sure your attic is well ventilated. Vents should be placed both high in the ridge and low in the soffit. If that isn’t possible, put vents in the gable ends. This keeps hot air from building up in the attic.

• Install a whole-house fan. A high-powered fan installed in the attic draws fresh air in through windows on lower floors and pushes stale air out through attic vents. When outside air temperatures stay below 85 degrees F, a whole-house fan may eliminate the need for an air conditioner altogether.