It is obvious that the smell of the washroom turns a little foul after using the toilet. This foul air needs to be driven out of there in order to keep the atmosphere in the washroom fresh and clear. Using an air freshener is only half the solution, but if there stale air is not driven out then the mix of smells could make the end result even worse. Also, this humidity is favorable for the development of molds and fungi in the washroom. This calls for the use of bathroom fans or exhaust fans. These fans are generally mounted on the window which is connected to exteriors of the house. The main purpose is to pump the air from inside the washroom out. It is generally connected at higher areas of the washroom as the warm air rises upwards.
Working of the exhaust fan
The rotation of the blades of the fan creates a pressure difference between the two sides of the fan. This pressure difference drives the air inside the washroom to leave. Cooler and fresh air enter from other places to fill this space created by the air that is being pushed out of the room.
Things to consider before buying a fan
The ventilation capacity of the fan is what needs to be considered before buying and installing it. This mainly depends on the size of the room. This is generally calculated in CFM(cubic feet per minute). In smaller bathrooms, a 50 CFM fan would be sufficient. But for larger bathrooms, the CFM should be more than the square footage of the entire washroom.
Another important thing to consider is the noise level. You do not want high CFM which comes with extreme noise as the washroom is supposed to be a peaceful place.
The design of the frame and blades must be in sync with the rest of the washroom. Though it is located at a higher position, it is connected directly to the exterior of the house, hence an auto opening duct system can help in preventing outside material from entering into the house when the fan is not in use.