Bathroom Exhaust Fans Are Important
Moisture and fumes from bathroom activities like showering and bathing can cause various bathroom damage, including mold, drywall damage, and wood damage. Inadequate ventilation can aggravate these problems. This is where a bathroom exhaust fan comes in. The fan not only provides air ventilation but also eliminates moisture, odors, and fumes from cleaning agents. This article discusses the importance of proper bathroom ventilation and the considerations for installing a bathroom exhaust fan that works effectively.
Proper Bathroom Ventilation
The two primary considerations for proper bathroom ventilation are adequate sizing and proper installation and exhaust.
Bathroom Exhaust Fan Sizing
Most builder-grade bathroom fans installed today are 50 cubic feet per minute (CFM) fans, which do not provide sufficient ventilation for an average-sized bathroom. For a bathroom with an 8-foot ceiling height, the general rule is to allow at least 1 CFM of ventilation for every square foot of room size for bathrooms under 100 square feet. For larger rooms, the recommendation is to add a minimum of 50 CFM for each toilet, sink, bathtub, or shower, and 100 CFM for jetted tubs. A larger CFM rating ensures faster ventilation. We recommend Energy Star 150 CFM fans as they run quietly and provide maximum ventilation. It is important to note that fans do not always perform consistently at the rated CFM on the box. According to the Building Professional Institute (BPI), 50 CFM bath fans only produce around 30 CFM of actual air exchange.
Proper Bathroom Fan Installation & Exhaust
All bath fans should be installed with an insulated duct routed through the roof and terminated on a dampered roof cap to prevent hot moist air from returning into the home. Exhausting the bath fan through open soffit vents is not recommended as it does not meet the code and can cause attic moisture problems, especially in cold climates. Attic fans that exhaust directly into the attic rather than outside can also cause various moisture issues, including attic mold, wet insulation, and wood rot to structural elements of the building.
The Attic Experts
We are experts in insulation and ventilation services, including bathroom exhaust fans in Chicago and all suburbs. We offer a free attic inspection and conduct a thorough inspection of your attic insulation, attic ventilation, and other home efficiency services. Please call us at 630.941.3800 with any questions or to request an inspection.