Ventilation fans are commonly installed in various locations within a building to exhaust stale air, odors, and moisture and introduce fresh air. Whether they need to be installed on the outside of the building depends on the type of ventilation fan and its intended purpose.
There are two primary types of ventilation fans:
Exhaust Fans: These fans are designed to remove air from a specific area or room and expel it to the outside. Exhaust fans are typically installed on exterior walls or in windows to vent air directly outside. They are commonly used in bathrooms, kitchens, and other spaces where moisture, odors, or pollutants need to be removed.
Supply or Intake Fans: These fans, as the name suggests, are used to bring fresh air into a building from the outside. They are often part of an HVAC system or used in conjunction with an exhaust system to maintain proper air circulation and ventilation. Supply or intake fans can be mounted on exterior walls, roofs, or ducted from outside into the building.
In summary, exhaust fans are typically installed on the outside to expel air from the building, while supply or intake fans are installed to bring fresh air into the building from the outside. Both types of fans play essential roles in maintaining indoor air quality and ensuring proper ventilation throughout the building. The exact placement and installation of ventilation fans depend on the specific needs and layout of the building. It's crucial to follow the manufacturer's guidelines and local building codes when installing ventilation fans to ensure their effectiveness and safety.