Luftbytte

Luftbytte, a Swedish term, translates to "air exchange" or "air change" in English. It refers to the process of replacing stale indoor air with fresh outdoor air. This exchange is crucial for maintaining good indoor air quality by removing pollutants, moisture, and odors, and replenishing oxygen levels.

There are several ways luftbytte can occur. Natural luftbytte happens through infiltration and exfiltration, where air leaks in and out of a building through cracks, gaps, and openings in the building envelope, as well as through open windows and doors. Mechanical luftbytte, on the other hand, is achieved through ventilation systems, such as exhaust fans and mechanical ventilation units (MVHR or HRV systems). These systems actively move air in and out of the building.

The rate of luftbytte is often measured in air changes per hour (ACH), indicating how many times the entire volume of air inside a space is replaced by fresh air within one hour. Maintaining an appropriate level of luftbytte is important for both occupant health and the structural integrity of a building. Too little luftbytte can lead to a buildup of indoor air pollutants and moisture, potentially causing health problems and mold growth. Conversely, excessive luftbytte can result in significant heat loss, increasing energy consumption for heating and cooling. Modern building design often focuses on controlled luftbytte to balance energy efficiency with healthy indoor air.