Any reason not to vent shower out soffit?


  #1  
Old 05-31-24, 08:16 AM
F
Member
Thread Starter
Join Date: Aug 2023
Posts: 35
Received 1 Upvote on 1 Post
Question Any reason not to vent shower out soffit?

Hi there, hope you're all doing well. Woke up to water coming through ceiling and confirmed it's from a sagging shower vent corrugated pipe that's old. It also runs about 20' and vents out the side of the house. I'm going to replace and whole vent and realized that it's only about 3' from the fan if I just vent out the bottom of the soffit instead.

Any reason not to do this? Searching around, some folks suggest that it could allow the shower moisture to then be sucked back up into the soffit and roof. Is that likely or any way around that?

Thanks for your time.
 

Top Answer

 
05-31-24, 05:07 PM
XSleeper's Avatar
XSleeper
XSleeper is offline
Group Moderator
Join Date: Dec 2004
Posts: 27,311
Received 1,975 Upvotes on 1,771 Posts
Assuming you have a building code where you live, section M1501.1, M1502.3 and M1504.3 specifically covers this. No to venting in soffits. But we don't know the exact code in your area... however that would not pass where I live for the exact reason you mention. Exhaust vents must be 3 feet from openings that might otherwise suck that air right back into the house. Like venting out your soffit would do.
 
  #2  
Old 05-31-24, 08:18 AM
F
Member
Thread Starter
Join Date: Aug 2023
Posts: 35
Received 1 Upvote on 1 Post
Forgot to mention: the soffit is the common vinyl vented (lots of tiny holes in it).
 
  #3  
Old 05-31-24, 08:28 AM
P
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 28,352
Received 2,319 Upvotes on 2,064 Posts
What specifically are you calling a vent? Is it the plumbing vent or are you talking about the ducting for the ventilation fan?

Bathroom exhaust fans can vent under soffits. The code says it cannot discharge into the attic but there is no prohibition against the vent being in the soffit. If you have vented soffit I don't think it is a good idea but it is not prohibited. If your soffits are solid then it's not an issue since the air can't get into the attic.

If it's a plumbing vent that should be vented vertically through the roof if any way possible.
 
  #4  
Old 05-31-24, 02:34 PM
F
Member
Thread Starter
Join Date: Aug 2023
Posts: 35
Received 1 Upvote on 1 Post
Thanks, I'm referring to the exhaust fan vent, apologies for the confusion. Appreciate the feedback about it not working great if the soffit is vented, which this one is.
 
  #5  
Old 05-31-24, 04:54 PM
Tolyn Ironhand's Avatar
Group Moderator
Join Date: Nov 2007
Location: United States
Posts: 14,484
Received 914 Upvotes on 772 Posts
A lot of times there is a barrier that holds the insulation back in the attic and prevents it from falling into the soffit. That barrier can be cardboard, OBS, or plywood.

Depending on the truss design there may not be enough room between the top wall plate and the roof sheathing for an insulated exhaust vent.

Even if you run the vent to the soffit you still need to cut a hole and install a vent cap. You can't just stuff the vent into the soffit and call it good.

Long story short: The best option is to install a roof vent.
 
FieldNotes voted this post useful.
  #6  
Old 05-31-24, 05:07 PM
XSleeper's Avatar
Group Moderator
Join Date: Dec 2004
Posts: 27,311
Received 1,975 Upvotes on 1,771 Posts
Assuming you have a building code where you live, section M1501.1, M1502.3 and M1504.3 specifically covers this. No to venting in soffits. But we don't know the exact code in your area... however that would not pass where I live for the exact reason you mention. Exhaust vents must be 3 feet from openings that might otherwise suck that air right back into the house. Like venting out your soffit would do.
 
FieldNotes, Tolyn Ironhand voted this post useful.
  #7  
Old 06-03-24, 07:39 PM
F
Member
Thread Starter
Join Date: Aug 2023
Posts: 35
Received 1 Upvote on 1 Post
Thanks everyone, you helped steer me clear of the soffit, appreciate the quick advice. Have a good week.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: