Question Regarding Bathroom Exhaust Fan - HVAC - DIY Chatroom Home Improvement Forum

Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > HVAC


Thread Tools Display Modes
Old 01-15-2011, 01:56 PM   #1
Join Date: Nov 2009
Location: Downriver Michigan
Posts: 86
Rewards Points: 75

Question regarding bathroom exhaust fan

Hey guys!

So I am interested in a home that was flipped this year.

Overall the work is pretty good and I'm content with it.

However there are a few things... one that I need some info on is this...

There are two bathrooms that both have exhaust vents. The vents go up into the attic with seperate uninsulted flexiable metal lines. The lines go up and are taped to support beams horitozntally allllllll the way to one of the attic soffits (over 30 feet). There are spots where the metal line sags 1/2 inch to an inch.

Is any of this setup a violation of any specific code? I REALLY want to tell him... nope you need two separate vents STRAIGHT up out of the attic via the roof.

Thanks guys!



DownRiverGuy is offline   Reply With Quote
Old 01-15-2011, 02:25 PM   #2
Chicago, IL
Michael Thomas's Avatar
Join Date: Jan 2008
Location: Chicago, IL
Posts: 1,037
Rewards Points: 500

Unless the manufacturer specifies a shorter length, insulation, hard pipe, or no reversed pitch, they are unfortunately allowed and I frequently see poorly functioning installations as a result:

Typically the installation instructions only say something like:

"The unit will operate most quietly and efficiently when located where the shortest possible duct run and minimum number of elbows will be needed."

One exception is Panasonic, their instructions prohibit some of these installation techniques:

Occasionally an AHJ will impose other restrictions, for example in some areas where I inspect they prohibit direct attachment for flex vent to the exterior termination and instead require had pipe through the wall or ceiling, so it may be worth checking with the local building department.


Home Inspections, Infrared (Thermal Imaging) Leak Identification and Inspection Services, Roof, Attic, Building, Basement and Foundation Moisture Intrusion and Water Leak Inspections, Troubled Building Consultations - Serving Chicago and Suburbs

Last edited by Michael Thomas; 01-15-2011 at 03:35 PM.
Michael Thomas is offline   Reply With Quote
Old 01-15-2011, 04:18 PM   #3
Join Date: Dec 2006
Posts: 17,158
Rewards Points: 6,652

They do make units, where the fan is actually remote, and would be one vent out of the building. Would be quieter and may be the better way, unless you have a light in the vent fans. Take a picture of the units and post back.
gregzoll is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
bathroom exhaust fan code AndyH24 General DIY Discussions 25 12-27-2010 08:33 PM
Can bathroom exhaust and dryer share same outside duct? benze HVAC 17 09-08-2010 02:24 PM
New wiring and switch for bathroom exhaust fan looking4help75 Electrical 9 06-27-2008 04:15 PM
Bathroom Exhaust Fan Ducting drtpdee HVAC 1 03-03-2008 06:47 PM
Bathroom exhaust question Horace HVAC 4 07-27-2006 07:54 AM

Top of Page | View New Posts


Search Engine Friendly URLs by vBSEO 3.6.1