As summer quietly gives way to crisp mornings, most of us instinctively reach for cozy blankets, pumpkin candles and an extra layer. But before you shut every window until spring, consider borrowing a centuries-old German tradition that’s having a moment.

It’s called lüften (pronounced LOOF-ten), which simply means “to air out.” Americans have recently given it the less-than-glamorous nickname “house burping,” but don’t let the name fool you. The practice is surprisingly elegant in its simplicity: open your windows wide for a few minutes each day to flush out stale indoor air and replace it with fresh outdoor air. As The New York Times recently noted, what Germans have done for generations has suddenly become America’s newest home wellness trend.

Why bother? Because as homes become increasingly airtight and energy efficient, they also do an excellent job of trapping moisture, odors and indoor pollutants. Cooking, cleaning products, furniture, candles (even simply breathing) can affect indoor air quality. Briefly opening windows creates a quick exchange of air without dramatically changing the temperature of your home. Experts say this simple habit can help reduce volatile organic compounds as well as allergens, discourage mold growth, and leave your home feeling noticeably fresher.

The secret isn’t leaving the windows cracked all day. According to The Spruce, “In summer, open all the windows about two times a day for 30 minutes to improve the indoor air quality. During the spring and fall seasons, shorten the amount of time the windows are open to about 10 to 15 minutes twice a day. When winter hits, you should only need to have the windows open for about five to 10 minutes twice a day.”

The New York Times notes that there are different terms for different types of lüften—which is a surefire way to impress your friends at your next party. “Querlüften is cross ventilation, wherein you open windows on opposite sides of the house, while the shock of freezing air as you ventilate in the winter is called a stosslüften.”

Of course, lüften isn’t a one-size-fits-all solution. Skip it during wildfire smoke events, poor air quality days or when pollen counts are especially high if allergies are a concern. In those situations, your HVAC system or an air purifier is likely the better choice.

Sometimes the best home improvements don’t require a contractor, a shopping trip or even a toolbox. Spend five minutes letting the outside in, and your house (and perhaps your sinuses!) just might thank you.