Forums | Home Repair | Home Improvement | Painting | Interior Decorating | Remodeling | Landscaping


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

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 01-25-2013, 11:24 AM   #1
Member
 
Join Date: Dec 2011
Location: Southern Illinois
Posts: 123
Share |
Default

Bathroom Vent Condensation staining ceiling


Hello Experts.

Bought a 30 y.o. house last winter and did extensive remodeling. Today we were dismayed to find a water stain adjoining the bathroom ceiling fan.

Last year I installed a Broan fan which attached to the existing aluminium flexible duct. You can see from the photo, where is a bit of a sag and I did feel a bit of water there.

The roof was replaced a couple of years ago and this is how they chose to connect the ducting. Nice, huh? Each bath routs to a Tee, then out to a covered vent. I never liked the setup, but chose not to address it. That side of the house faces the street and I was hoping to not blemish the clean roof by installing a vent.

I was wondering about installing a sideways vent, but you can see from the third photo that I would probably have to have a down-turn right at the wall.

So folks, would you have any suggestions? First, I would like to know the best practices for installing a bathroom vent. Is the flexible foil standard?

Second, drifting away from best practices, do you see any other way to handle this, so I don't have to cut a hole in the front of the roof?

Thank you very much.

Murph.
Attached Thumbnails
Bathroom Vent Condensation staining ceiling-image00002.jpg   Bathroom Vent Condensation staining ceiling-image00004.jpg   Bathroom Vent Condensation staining ceiling-image00003.jpg  

Last edited by MurphyMan; 01-25-2013 at 11:46 AM.
MurphyMan is offline   Reply With Quote
Old 01-25-2013, 11:31 AM   #2
Roofmaster
 
Join Date: Oct 2012
Location: Maryland
Posts: 3,406
Default

Bathroom Vent Condensation staining ceiling


why don't you pipe it with rigid PVC right in the attic floor, under insulation and out the soffit? You are getting condensation in the attic, and you have run that flex duct way too far, and with dips in it to pond water.
__________________
" A lot of men build things, and a lot of things fall down "

jagans is offline   Reply With Quote
The Following 2 Users Say Thank You to jagans For This Useful Post:
joecaption (01-25-2013), MurphyMan (01-25-2013)
Old 01-25-2013, 01:17 PM   #3
Member
 
Join Date: Dec 2011
Location: Southern Illinois
Posts: 123
Default

Bathroom Vent Condensation staining ceiling


Quote:
Originally Posted by jagans View Post
why don't you pipe it with rigid PVC right in the attic floor, under insulation and out the soffit? You are getting condensation in the attic, and you have run that flex duct way too far, and with dips in it to pond water.
Won't that cause the warm moist exhaust air to be sucked up into the soffit vents?
MurphyMan is offline   Reply With Quote
Old 01-25-2013, 01:41 PM   #4
Member
 
Join Date: Dec 2011
Location: Southern Illinois
Posts: 123
Default

Bathroom Vent Condensation staining ceiling


Here is a photo of the soffit. The photo is taken, just outside of the entryway vestibule.

It's hard to see, but the soffit is not parallel to the ground. It is plywood and has the same slant as the roof line, forming kind of an umbrella effect, I think. Actually, I think the existing soffit vents aren't big enough, but that is another issue, I guess.
Attached Thumbnails
Bathroom Vent Condensation staining ceiling-image00005.jpg   Bathroom Vent Condensation staining ceiling-01.jpg  
MurphyMan is offline   Reply With Quote
Old 01-25-2013, 03:19 PM   #5
Roofmaster
 
Join Date: Oct 2012
Location: Maryland
Posts: 3,406
Default

Bathroom Vent Condensation staining ceiling


Well, I have a ranch, and mine is vented like that and I have never had a problem, but you sure dont want to dump poopie smelling air out into your entrance foyer. Can you go the other way?

You are correct re soffit venting. You don't have enough to make any difference at all.

Nice house though!

Forgive my saying so, but have you had problems with ice damming? The sheathing near the eaves looks really discolored. Im pretty sure you need to fix your eaves venting on this home. I dont get the half baked wood blocking of the edges of the sheathing either. Just saying.
__________________
" A lot of men build things, and a lot of things fall down "


Last edited by jagans; 01-25-2013 at 03:29 PM.
jagans is offline   Reply With Quote
Old 01-25-2013, 03:41 PM   #6
Member
 
Join Date: Dec 2011
Location: Southern Illinois
Posts: 123
Default

Bathroom Vent Condensation staining ceiling


Quote:
Originally Posted by jagans View Post
Well, I have a ranch, and mine is vented like that and I have never had a problem, but you sure dont want to dump poopie smelling air out into your entrance foyer. Can you go the other way?

You are correct re soffit venting. You don't have enough to make any difference at all.

Nice house though!

Forgive my saying so, but have you had problems with ice damming? The sheathing near the eaves looks really discolored. Im pretty sure you need to fix your eaves venting on this home.
Thanks - we like the new place. We moved from a little ranch house right next to busy train tracks. We are in southern Illinois and typically only get about 6" of snow for the whole winter. Having said that, we got about 12" just after Christmas. Last year we only had about 1/2" total.

I saw somewhere the attic vent should be: area of the attic divided by 150. Then split the result between the ridge vent and the soffit vents. The soffit should be equal to, or larger, than the ridge vent. Does this sound correct?

I haven't measured the attic yet. The spacing for the ridge vent only appears to be about 1" on either side to the center beam. Last summer, during the heat wave, my digital thermometer was reading 140 F in the attic, and I suspect that was the upper limit for the device. I had one roofing guy come out and he glanced at the vents and said they were adequate. Of course, he wasn't there when it was 140 degrees in there.
MurphyMan is offline   Reply With Quote
Old 01-25-2013, 03:44 PM   #7
Member
 
Join Date: Dec 2011
Location: Southern Illinois
Posts: 123
Default

Bathroom Vent Condensation staining ceiling


Quote:
Originally Posted by jagans View Post

Forgive my saying so, but have you had problems with ice damming? The sheathing near the eaves looks really discolored. Im pretty sure you need to fix your eaves venting on this home. I dont get the half baked wood blocking of the edges of the sheathing either. Just saying.
I have had several people comment on the half-baked wood blocking. We had a huge storm in our area about 4 years ago and every other home got a new roof. I imagine that blocking was done at that time.

Yes, it's a nice house, but there are several areas were the builder cut corners. Code enforcement isn't real strong in a lot of these parts.
MurphyMan is offline   Reply With Quote
Old 01-25-2013, 04:22 PM   #8
Member
 
Join Date: Nov 2011
Location: Hartfield VA
Posts: 24,528
Default

Bathroom Vent Condensation staining ceiling


There's not even close to enough venting in those soffits.
joecaption is offline   Reply With Quote
Old 01-25-2013, 06:22 PM   #9
Roofmaster
 
Join Date: Oct 2012
Location: Maryland
Posts: 3,406
Default

Bathroom Vent Condensation staining ceiling


The real fact about eaves venting is that you need all that you can get. I always recommend throwing the calculator in the lake and go continuous vented eaves. The fact is that eaves venting gets about 60 % clogged with insects, pollen, atmospheric dirt and misplaced insulation very fast, and all those wonderful calculations go to aunt Marys House. You need continuous vented soffit and ridge venting, and baffles at the eaves. What you have is simply inadequate, and should have been picked up during your home inspection, if you had one. The blocking should have been picked up too, IMO.
__________________
" A lot of men build things, and a lot of things fall down "

jagans is offline   Reply With Quote
Old 01-25-2013, 06:37 PM   #10
Registered User
 
Join Date: Mar 2009
Posts: 9,886
Default

Bathroom Vent Condensation staining ceiling


I'd go out the gable end, first, second out the roof, and last the soffit. You don't want/need bathroom moist air in the attic space. Definitely change the ducting to straight pipe as said. Try to use 45* elbows rather than 90's. Foil tape the joints, including the individual elbow ones, support with metal hangers. INSULATE per code (or more) when passing through an unconditioned space (attic) to prevent/diminish condensation. Go one size up when using flex;http://rockwallcontrols.com/Resident...ag=air-ducting Best not to use it at all for air flow. With all the folds (supposed to be fully stretched when used) to catch extra condensation and restricted air flow, and easy to restrict diameter with sags, sharp turns, supports required per code; I'm surprised it has a market... what is the distance run to the gable?

Gary
__________________
Clothes taking longer to dry?
Clean the dryer screen in HOT water if using fabric softener sheets.
They leave a residue that impedes air-flow, costing you money.
Clean the ducting in the last six months? 17,000 dryer fires annually!
Gary in WA is offline   Reply With Quote
Old 01-25-2013, 08:29 PM   #11
Roofmaster
 
Join Date: Oct 2012
Location: Maryland
Posts: 3,406
Default

Bathroom Vent Condensation staining ceiling


Gary is probably correct here, maybe. A bathroom (My Bathrooms Anyway) do not generally produce the level of condensation that would be cause for concern to me. It is not like a gas fired appliance wherein constant steam and condensate can be expected. I have had no problems at all in MD, your mileage may differ.
__________________
" A lot of men build things, and a lot of things fall down "

jagans is offline   Reply With Quote
Old 01-26-2013, 02:45 PM   #12
Registered User
 
Join Date: Mar 2009
Posts: 9,886
Default

Bathroom Vent Condensation staining ceiling


Maybe, lol. Family of four with 10 minute showers = up to a pint of moisture per day; http://www.buildingscience.com/docum...and-rot-houses

Clear up to 2003, code didn't require bathroom vent to terminate outdoors (someone correct me if wrong); http://publicecodes.cyberregs.com/ic..._15_par011.htm

2006 had to exhaust bath fans outside, not into an attic as we see plenty of members with moisture problems from that; http://publicecodes.cyberregs.com/ic..._15_sec001.htm

Important enough to amend in the IRC (from moisture problems, not smell), I feel it's important enough to add in an answer. I hope this clears it up some for you.

Gary
PS are you opening a window also? Are you taking cold showers/baths? Are you taking -2 minute showers?
__________________
Clothes taking longer to dry?
Clean the dryer screen in HOT water if using fabric softener sheets.
They leave a residue that impedes air-flow, costing you money.
Clean the ducting in the last six months? 17,000 dryer fires annually!

Last edited by Gary in WA; 01-27-2013 at 11:30 AM. Reason: Added questions.
Gary in WA is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
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
Installing a plumbing vent on a basement bathroom Breadmaker Plumbing 4 09-21-2012 08:18 PM
ceiling paint in bathroom gorilla325 Painting 15 09-10-2012 06:07 PM
bathroom vent fan - condensation problem jaspar General DIY Discussions 16 03-23-2012 10:54 AM
Help with basement bathroom vent satchfan Plumbing 3 12-26-2010 09:35 PM
Birds bathroom vent mess Wheats General DIY Discussions 0 11-28-2010 08:04 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.