Each time the kitchen and bathroom are used, they generate humidity and odors that need to be exhausted outside to maintain a healthy indoor environment. HUD did not require mechanical ventilation of kitchens and baths until the 1994 update of the HUD-code, but most manufacturers were already installing exhaust fans because of customer demand.

   The bathroom fan is required to move 50 cfm (cubic feet of air per minute). Ordinarily, the bathroom light and exhaust fans are on separate switches but, if there is an ongoing moisture problem in a bathroom, you have choice of three ways to get more air exhausted from the bathroom:

1. Tie the circuit for the exhaust fan to the same switch as the lighting for the bathroom. This is the cheapest solution and guarantees that when the bathroom is being used the fan is on, but will not keep the fan operating as long as the next two solutions. 
2. Replace the on/off switch for the bathroom exhaust fan with a timer switch, like the one shown below. You can adjust it to continue running for several minutes after you leave the room.
3. The newest technology is a fan control switch that incorporates a humidistat device that doesn’t turn the fan off until the humidity and temperature in the room have reached an acceptable level. A photo of one made by Panasonic® is below and, depending on the brand, this hi-tech solution will set you back $40 to $60.

    A kitchen exhaust fan must provide a minimum of 100 cfm and can be the through-the-wall exhaust type or a hood fan over the range ducted to the exterior. Both kitchen and bathroom fans must have a backdraft damper, which is a hinged flap that closes when the fan is off to prevent air leakage, and relies on gravity to shut. 

        Go to our HUD-CODE FOR MOBILE HOMES page for a listing of our other HUD-code articles. Also, see our blog post How energy efficient is a mobile home? 

Here’s links to a collection of our blog posts about MOBILE/MANUFACTURED HOMES:

• Where can I file a complaint if I have problems with my new or used manufactured/mobile home in Florida?

• What are the most common defects in mobile/manufactured home foundation piers?

• How do I determine the age of a very old mobile home?

• What is a "HUD label verification letter" for a mobile/manufactured home?  

• When did a ground cover vapor barrier (plastic sheet) become required under a mobile/manufactured home? 

• Is it safe to go under a mobile home? 

• Are older mobile homes unsafe? 

• What do I need to know about buying a foreclosed mobile home? 

• Does it make sense to buy an older mobile home and remodel it? 

• Where do I find the vehicle identification number (VIN) on a mobile home? 

• How do I find out how old a mobile home is and who manufactured it?

• What is the right price for a used mobile home?

• When were the first double-wide mobile homes manufactured?

• How do I upgrade my old (pre-1976) mobile home to meet HUD standards?

• What size air conditioner is right for my mobile home? 

• Can you move an older mobile home in Florida? 

• What does the HUD tag look like and where do I find it on a mobile home? 

• Can you put a zone 1 mobile home in Florida?

• How can I remove water under my mobile home?

• What's the differences between a trailer, a mobile home, a manufactured home, and a modular home? 

• What is a D-sticker mobile home? 

• What are the tie-down requirements for a mobile home?

• How fireproof is a mobile home?  

• Can I install a mobile home myself?

• What is a Park Model mobile home?  

• Does an addition to a mobile home have to comply with the HUD Code? 

• What walls can I remove in a mobile home?

• What can I do to prevent dampness and mold in my mobile home? 

• How can I tell if a mobile home is well constructed?

• How can I tell the difference between a manufactured home and a modular home?

    Visit our HEATING AND AIR CONDITIONING and MOBILE/MANUFACTURED HOMES pages for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.