Bathroom Exhaust Line Tear

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thapranksta

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I also posted this in the Plumbing section because I wasn't sure of where this goes exactly. This was discovered while working on studs and subfloor so maybe it goes here.

To sum up, we are replacing subfloor upstairs and applying BIN primer in an attempt to get rid of the smell of cat urine in our home. Upon opening up the floor, we noticed that there was a white duct line which seems to be the exhaust line for our downstairs bathroom. The duct line has a tear below it and we can see what appears to be new signs of water leakage on a piece of framing. There is also a tiny sliver of blackness (1/16'' to 1/8'') on the edge of an I-joist on the wall where the exhaust line exits the house. I have pictures below.

I do not believe we did anything in particular to cause this as we only removed subfloor but this was visible soon after we removed the subfloor. Not sure if it is just a coincidence and we are lucky we happened to be opening the subfloor at this time. I was wondering if we need to call in a professional to fix this or this is something easy we can repair. What alarms me is that there appears to be mildew on the exhaust line as well and I have no idea how extensive it is.



damage on board where exhaust exits house at the top of the picture
IMAG1691.jpg


mildew
IMAG1692.jpg


kinda hard to see but this the tear under the line
IMAG1693.jpg


exhaust exit
IMAG1690.jpg


Thanks.
 
If this were my house, I'd remove the cheap plastic line and replace it with metal pipe. Just my :2cents:
 
The exhaust line runs from my first floor half bath up to the second floor under the subfloor. Complete replacement would be my preference but it looks as though I would have to do a lot of work.
 
When's the next time you will have access open again? I think it will be a while till you're this close again. If it's torn where you can see, what's hidden you don't see?
 
I doubt I would have a reason anytime soon to reopen. I cannot see the full path it takes to get to the bathroom. I only have a small section of my upstairs open. Looking under the subfloor with a flashlight I can see it go straight for maybe 6 or 7 feet and then it veers to the side and takes some route I cannot see to the downstair bath.
 
Change whart you can see now evan remove some more subfloor and change as much as possible.
 
Is it common to direct the bathroom fan exhaust out the side of the house like that instead of the roof?
 
Yes and it is better if it is insulated so the air stays warm until it gets outside, Or moisture will condence in the duct work.
 
Thanks guys. Now I need to decide if I should hire someone to do this for me or should I attempt this myself.

The only insulation was on the wall right at the exit point.

Edit: Looks like I will need a ladder to reach the vent outside on the brick wall.
 
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If you can get to to inside where it enters the brick you may not need to reach the outside at all.
 
If you took out the subfloor yourself, then you have the hard part under control. Replacing the vent pipe should be pretty easy, as long as you can access it.
By taking a good look at both ends - where the bathroom fan is, and where the vent is on the outside - you can pretty well figure out the route of the pipe and the length. I don't think you have to rip out your whole floor to do this. You can probably just open a hole where the pipe turns and work it from there.
 
Just to be clear they do use a flexable insulated duct, they like it because there are no joins so if you are using hard duct, tape the joints.
 
Is the insulated flexible vent line the best one to use or the rigid variety? There are a few hangers in the subfloor that the current line is tied to and I may not be able to reach them if I don't open up more of the floor. Yes, I have successfully removed subfloor, the problem is I have not had a chance to install any yet.

I was getting ready to try to create supports for attaching the new subfloor panels around the wall using boxes when I noticed this. As far as attaching to the existing flooring perpendicular to the joists and away from the walls, I cut pieces of 3/4'' OSB into 3.5'' wide strips and attached them between the joists under the existing subfloor leaving half exposed to attach the new subfloor panels. I wanted the surface area of 2x4s but they seemed too heavy for the situation. It's not tongue and groove obviously but it seems as though it would be pretty solid.

I think it would be easier if my wife and kids were out of town for about a week. There'd be no one making me second guess every piece of demolition work that needs to get done and making this stressful.
 
Any time we don't have T&G we use 2x4 blocks to make the joint with glue. Better air flow in straght pipe on a long run.
 
Ok, so you're saying it might be fine to lay the pipe flat under the subfloor without suspending it at all and that the hangers already installed didn't really help.

2x4s and glue between joints...I can still do it that way if it will create a stronger hold. On the strips of OSB, I just used screws and no glue but I have no secured any new subfloor to it yet. I could remove the OSB strips pretty easily at this point by just unscrewing it.
 
You are saying OSB can we suspect you mean Adventech flooring or something like that, that looks like OSB. That will work fine. Glue just makes it better or at least later when it squeeks you can say , it was glued!!
 
Yes, I mean Advantech. I am still learning all the terminology. As far as attaching the subfloor right by the walls, are the boxes I am building the way to go or can that area be attached safely with blocks too?
 
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It was T&G but I cut those edges off with a circular saw because I thought it would just weaken the connections to the existing subfloor. I cut two pieces of subfloor to fit in the cutout shown in the pictures.

My main question right now is really what is the best way to stabilize the subfloor near the wall as I had to cut out a corner? I will post pictures later to illustrate further.

Thanks guys.
 

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