Ersättningsluft

Ersättningsluft, often translated as make-up air or replacement air, refers to the air introduced into a building to compensate for air that has been intentionally or unintentionally removed. This removal can occur through various building systems such as exhaust fans in kitchens, bathrooms, laboratories, or industrial processes. Without adequate replacement air, these exhaust systems can create negative pressure within the building.

Negative pressure can lead to several undesirable consequences. It can cause drafts as unconditioned outside air is drawn in through unintended cracks and openings in the building envelope. This can also result in moisture issues, as warm, moist indoor air may be pushed into colder wall cavities, leading to condensation and potential mold growth. Furthermore, the effectiveness of exhaust systems can be compromised if they are not supplied with sufficient air, as they may struggle to draw air efficiently.

Ersättningsluft systems are designed to introduce fresh outside air in a controlled manner. This can be achieved through dedicated make-up air units, which often include filtration and heating or cooling capabilities to condition the incoming air before it enters the building. In some cases, simple passive inlets or fan-assisted systems can be employed. The design and implementation of ersättningsluft systems are crucial for maintaining indoor air quality, ensuring the proper functioning of building systems, and preventing energy losses associated with uncontrolled air infiltration. The amount of ersättningsluft required is typically determined by the volume and rate of air being exhausted from the building.