Purchase the exhaust fan (if you don't already have one) and a roof vent. Roof vents can be dome-shaped, square (like the one ...

By using solar power, these attic fans can help increase ventilation and airflow without adding utility cost. Indoor air quality, reasonable energy bills, and the health of your roof depend upon ...

From the fan, a single exhaust duct exits through the roof. Each bathroom has its own switch and operates independently.