Bathroom Ventilation

Structural Damage

The major byproduct created by your bathroom is moisture. If you've ever tried to see your image after showering, you know this to be true. But condensation and moisture aren't limited to the bathroom vanity mirror but rather collect on every surface of your bathroom including the grouting around the tiles, the walls and the ceiling. The constant humidity in your bathroom comes with collateral damage in the form of fungus and mold which can lead to wood rot. Wood rot can lead to major structural damage which can endanger your home and lead to expensive repair work

Moisture Buildup

A high quality bathroom exhaust fan can waft away humidity and prevent moisture buildup by venting moist air outside your home. That means that a good exhaust fan is a good investment. Running an exhaust fan for 20 minutes after a shower will protect your home from moisture damage.

Bathroom ceiling fans are known as intermittent ventilation. These fans act to collect and remove moisture as it is formed, before it can spread and wreak havoc elsewhere in your home. Ceiling fans aren't just useful in the bathroom, but can serve you well in other home areas like kitchens, utility rooms, workshops, exercise rooms, home offices, and garages, where they don't just remove moisture, but remove pollutants and odors, as well.

But fans come in all shapes in sizes and choosing the right fan takes knowledge. A simple guideline to keep in mind is that bathrooms of up to 100 square feet in area need an exhaust fan which can provide 1 cubic foot per minute (cfm) with eight air changes every hour. So, if your bathroom is 8' x 5' with an 8' ceiling, you have 40 square feet (sq ft) of bathroom area to vent. That means you'll need a fan with a rating of 40 cfm.

Automatic Timer

A larger bathroom requires a different solution in the form of a 150 cfm fan which can pull in all the air from the room and exhaust it at a central location. Install the fan over or close by the shower or tub, if possible, or over the toilet in an enclosed powder room. Since you'll want the fan to be left on for 20 minutes after each shower or bath, some find it convenient to install an automatic timer on the exhaust fan.

If after installation, you find that bathroom mirrors continue to fog up or you see that the grill of the exhaust fan is dripping, you may have an issue of faulty duct work performed during the installation of the fan which now prevents the moisture from venting to the outside. You may need to insulate the ducts or check to see if a roof jack may be allowing rain into a duct. Condensation may also occur when the warmer, moist air of your home hits the colder surface of the air duct, creating a cold bridge.

Fans can be noisy and sound levels are measured in sones. Noisier fans have a higher sone level. The lower the sone level, the higher the price of the fan. You'll want to purchase the quietest fan you can afford. It's important to keep in mind that improper installation can make even the lowest sone fan sound loud. A duct that is too small or installed in such a way that it gyrates or has kinks will defeat the purpose of your having invested in a quieter fan model.