Seems like a fairly easy question that the exhaust fan should go in the bathroom – right? The simple answer is yes, but we want to look into it a little deeper than that.
When using an exhaust fan inside a bathroom, the exact location can have a large impact on the effectiveness of the fan. For instance, in a typical bathroom, the shower is going to produce the most amount of moisture that needs to be exhausted out of the home. By placing the fan within the shower stall, you are increasing the effectiveness of the fan as the moisture can come straight up into the fan and out of the home. Conversely, if the fan is on the other side of the room, the moisture from the shower has to travel across the room and out.
CAUTION: In order for a fan to be used in the shower stall it needs to be tested and approved for this use. It needs to say something to the effect of “Approved for tub/shower use on a GFCI circuit”. The GFCI (Ground Fault Circuit Interrupter) is a safety feature that will shut the power off if moisture causes a hazard. Fans that include a heater function should never be used inside a shower stall.
If your fan can’t be used inside the stall, it is suggested that it be installed right outside of the stall – minimizing the distance the moisture has to travel. In larger bathrooms, two fans might be necessary. One installed in the shower stall and the other installed above the toilet. Once again, the goal is to locate the fans so they are as close to the source of contamination (moisture or odor) as possible.
Exhaust fans are no longer just for the bathroom. In future post we will look at whole house ventilation as well as ventilating areas such as garages, laundry and utility rooms.