'Luften' Is The German Practice We All Should Be Doing In The Winter
When Nancy Lundrum, a professor at Munich Business School, moved to Germany three and a half years ago, she noticed an interesting clause in her rental agreement: lüften.
The term sparked some confusion for Lundrum, but she quickly caught onto the practice, which is a ventilation technique designed to encourage airflow throughout a property. The method, which originated in Germany, typically involves creating a strong draft by opening windows wide ― often on opposite sides of living spaces ― to facilitate a complete air exchange.
There are two types of lüften, called “Stoßlüften” (shock ventilation) and “querlüften” (cross-ventilation). The former requires windows in a single room to be opened for a short, intensive period. During colder months, Germans typically perform Stoßlüften for about 15 minutes, two to three times daily.
On the other hand, querlüften requires all the windows in a home or building to be opened for cross-ventilation throughout the premises. During the height of the COVID pandemic, the government advocated this, thinking that ventilation would help ward off the virus in enclosed spaces. The general idea for both processes is to replace “stuffy” air with fresh, new air.
Lüften, regardless of the type, is a timed procedure that Germans take seriously as part of their daily routine, and other parts of the world are catching on. Is the buzz really merited? Experts weigh in on how to apply this practice.
The Proper Way To Lüften
Many people confuse lüften with simply opening windows to let some fresh air in. While replacing stale air in a home with fresh air is indeed the main idea, there is more precision involved.
According to Glenn Gault, the CEO of Gault Heating & Cooling, the first step is to open your windows fully instead of just cracking them open. During cold weather, 5-10 minutes of ventilation is typically sufficient, while warmer weather might require 20-30 minutes. The process should be repeated two to three times per day, ideally in the morning, midday and evening.
If you’re going for cross-ventilation, open windows on opposing sides of your house or apartment. Be sure to turn off your heat during this time to conserve energy (particularly if you’re going to air out your home for longer periods of time).
It’s worth noting that it’s not advisable to open the front doors when practicing lüften, particularly if they’re unattended. Besides the obvious safety concerns, lüften creates a controlled movement of air between specific open windows, and this ensures a quick air exchange without significant heat loss.
As Gault explained, opening the front door disrupts the pathway for fresh outdoor air, making this method less effective and instead letting in too much cold air. This could in turn put your heating system on overdrive.
The Benefits Of Lüften
This centuries-old practice has numerous scientifically supported advantages. According to Allen Rathey, director at Indoor Health Council, the ritual eliminates accumulated indoor pollutants, including CO2, volatile organic compounds (VOCs), allergens and other airborne contaminants. Exposure to these particles over time can cause headaches, dizziness, nausea and irritation.
Further, lüften can help lower indoor humidity levels (assuming that the outdoor air is drier than indoor air) and reduce conditions favorable to bacterial and mold growth.
“There is also the mental, emotional and physical benefit of breathing fresher air,” Rathey added, emphasizing how cleaner air helps you get better sleep and increases mental alertness.
In Germany, Lundrum said the highly insulated buildings require intentional ventilation to maintain healthy indoor air quality and prevent moisture-related issues, making the traditional practice of lüften not just a cultural habit but a necessary aspect of modern sustainable living.
“I went out of town for four days and my daughters did not ventilate the apartment while I was gone. When I returned home, every window in the apartment and the patio door were completely covered with condensation and there were large puddles of water on the floor and mold growing along the seals of the windows,” Lundrum said. “We lüftened and the condensation was gone in half an hour.”
Ready to give it a try?
