Installing a Bathroom Vent and Exhaust Fan
This >catskill houseblogger faced a problem that many homeowners with older homes must deal with and that is proper bathroom ventilation. His bathroom is located in the middle of the home which makes this problem a bit more complicated but his installation went smoothly and it all started with determining the proper CFM (cubic foot per minute) for his bathroom size.
The basic standard for a bathroom ventilation fan is it must be able to change the room air 8 times in an hour. To calculate that is pretty easy if you have bathrooms with 8 foot ceilings. Basically it is 1 Cubic Foot per Minute (CFM) for every 1 square foot of floor space, so if you have a bathroom that is 10 ft by 10 ft (or 100 square feet) a 100 CFM ventilation fan is needed. For bathrooms larger that 100 square feet, the ventilation rate depends on the number and type of fixtures in the bathroom.
He also mentions "make up air" which is necessary for proper ventilation and not always covered in DIY guides.javascript:void(0);
Some How-To's for bathroom fan installation
Home Depot
Lowes
Decorative Fan Choices
