Please proof this article: Bathroom ventilation ducts and fans.

[Nick Gromicko]

http://www.nachi.org/bathroom-ventil...ducts-fans.htm

[Christopher Currins]

This statement, last paragraph, (in blue) is repeated.

Have smooth interiors. Ridges will encourage vapor to condense, allowing water to backflow into the exhaust fan or leak through joints onto vulnerable surfaces.Above all else, a bathroom ventilation fan should be connected to a duct capable of venting water vapor and odors into the outdoors. Mold growth within the bathroom or attic is a clear indication of improper ventilation that must be corrected in order to avoid structural decay and respiratory health issues.

A bathroom ventilation fan should be connected to a duct capable of venting water vapor and odors into the outdoors. Mold growth within the bathroom or attic is a clear indication of improper ventilation that must be corrected in order to avoid structural decay and respiratory health issues.

[rmaday]

Good article. I'm not particulary fond of

"Inspectors can test for adequate fan airflow with a chemical smoke pencil or a powder puff bottle."

That's setting an expectation for the client that is not in the SOP.

As a tip for inspectors, it makes sense.

IMO any article for the public should not say what inspectors can, should or must do, unless it specifically included in the SOP.

[Marcel R. Cyr]

Originally Posted by rmaday

Good article. I'm not particulary fond of

"Inspectors can test for adequate fan airflow with a chemical smoke pencil or a powder puff bottle."

That's setting an expectation for the client that is not in the SOP.

As a tip for inspectors, it makes sense.

IMO any article for the public should not say what inspectors can, should or must do, unless it specifically included in the SOP.

I also agree with Rick on this one.

Also would like to add to this one;


Ventilation ducts must:

• Terminate outdoors. Ducts should never terminate within the building envelope.
• Contain a screen or louvered (angled) slats at its termination to prevent bird, rodent and insect entry.
• Be as short and straight as possible and avoid turns. Longer ducts allow more time for vapor to condense and also force the exhaust fan to work harder.
• Be insulated, especially in cooler climates. Cold ducts will encourage condensation.
• Protrude at least several inches from the roof.
• Be equipped with a roof termination cap that protects the duct from the elements.
• Installed per Manufacturers Recommendations.

[Nick Gromicko]

Thanks as always!