# Bathroom Exhaust Line Tear



## thapranksta

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






mildew





kinda hard to see but this the tear under the line





exhaust exit





Thanks.


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## oldognewtrick

If this were my house, I'd remove the cheap plastic line and replace it with metal pipe. Just my :2cents:


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## thapranksta

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.


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## oldognewtrick

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?


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## thapranksta

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.


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## nealtw

Change whart you can see now evan remove some more subfloor and change as much as possible.


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## thapranksta

Is it common to direct the bathroom fan exhaust out the side of the house like that instead of the roof?


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## nealtw

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.


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## thapranksta

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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## nealtw

If you can get to to inside where it enters the brick you may not need to reach the outside at all.


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## slownsteady

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.


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## nealtw

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.


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## thapranksta

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.


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## nealtw

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.


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## slownsteady

The hangers usually create choke points in flexible pipe as the pipe sags around them.


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## thapranksta

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.


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## nealtw

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!!


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## thapranksta

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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## nealtw

So this is T&G, do you need instruction on how to start, where to glue, and so on?


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## thapranksta

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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## thapranksta

Whole cutout






Two pieces of Advantech with T&G sawed off placed inside cutout





Pieces of Advantech currently screwed to existing floor between joists.





Box I built to support edge of new subfloor by the wall parallel to joists.





Is the box parallel to the floor joists a good idea?  It is a size where I have to apply a little pressure to wedge it in there.  A little less than half of the top of the box (1.5'' or so) will be exposed for screwing down the subfloor.  If the box is a good idea, do I need to build boxes for the wall perpendicular to the wall as well or can I use strips of the flooring like I did for the part connecting to the middle of the floor?  Hope I'm making sense.


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## slownsteady

you might find this video helpful, although your hole is a bit bigger:
https://youtu.be/LI7VUyzYA6U

I see one end of the box is resting on framing, is the other end resting on framing too?


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## thapranksta

Yeah, the other end will be resting on the frame as well.  It isn't in the picture.


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## nealtw

You do need solid blocking on both sides every space, Longer screws, screw down thru the wall plate for you blocking against the wall.


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## thapranksta

I've gone forward with this project.  I opened up more of the subfloor.  I planned to put the same subfloor back down in those places since it didn't need replacement but a small layer on top of the I-joists came up when I removed one part of the subfloor and I may have to install a totally new piece for that one.  I've got 4'' insulated R6 flexible ducting.  I am not sure if I will be able to install all the ducting from the inside of the house as the exit hole seems as though it is not the cleanest job and the mildewed ducting completely extends through the hole. I will attempt to post pictures later.


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## slownsteady

We like to hear about progress. Just curious, Why did you stick with flexible pipe?


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## thapranksta

I stuck with flexible pipe because it was readily available insulated and it would be easier to try to snake through the existing holes..


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## thapranksta

Here are more pics as promised.  I have more of a dilemma on my hand now as you will see below.  I cut cavities that will allow me to access all the ducting in the upstairs bonus room where it is routed under the subfloor and exits the house.

Picture of fan opening in 1st floor bathroom ceiling (7.5'' x 7.5'')





Pictures of floor cavities and Subfloor pieces removed










This is the end of the line for the venting from the room upstairs where the flexible ducting exits the house.  On the other side of the wall at the top of the picture is a tiled bathroom unfortunately and the 1st floor bathroom that the ducting runs from appears right below it.






Seems like I have three options:  1) try to cut a large enough hole in the 1st floor bath ceiling to remove the current fan box and install a new one, 2) try to cut a larger access hole in the I-joist in the bonus room which seems like it could start affecting the structural integrity, or 3) gut the bathroom floor above it, removing the tile and subfloor and creating a much larger project but having direct access to the area above the bathroom fan.

Ugh.


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## thapranksta

I went ahead and replaced the duct vent outside.  I found that the flexible pipe was screwed directly to the outside vent itself.  Later I found out why besides the cost reduction.  The hole was much too small for a straight pipe to fit completely through it.  I did use a straight pipe after much effort sanding and forcing the pipe through the exit hole. [Someone with  a dirty mind might have fun with my wording.  lol.]  I also found that the vent and end of the flexible piping was home to bugs at one point in time.  I suspect rodents might have also been through there.

Now I can't get the vent outside to sit flush with the house because the collar will not fit through the hole. Is there any way to cover this gap and make it look more aesthetically pleasing without renting masonry hole cutting tools.


No way to stop bugs from getting in there.





This came out as soon as I disconnected the vent from the pipe.





Straight pipe inside





Outside - new vent with a flap to keep bugs out and also a pest guard. The gap around it is a little unsightly.  I applied caulk but there's no way it could ever reach it.


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## thapranksta

I fixed the gap problem with a masonry chisel I went to pick up.  I put more caulk behind it.  Inside where there are gaps between the straight pipe and wood wall, I plan to put steel wool and put caulk on top of it.  Then there will be insulation placed around the pipe as well.  I've still got to figure out how to get to the bathroom fan duct connection safely though before I can change out the whole thing.  A small victory in the grand scheme of things but a victory nonetheless.


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## nealtw

You have a smooth ceiling in the bathroom, you could just cut a bigger hole in the drywall and patch after the new fan is installed. Sorry for the delay I missed your posts.


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## thapranksta

It pays to measure instead of "eyeballing".  I discovered I did not need to worry about ripping up the bathroom on the other side of the wall.  I found that the bathroom fan was actually located over a hallway leading into an upstairs bedroom.

BINGO!





Duct's Route over 1st floor bathroom ceiling





Uninsulated, mildewed duct removed





Flexible 4'' R6 Insulated Duct (Replacement Candidate)





Now I've got some more decisions to finalize.  Do I need to worry about using a hangar over the plumbing in the bathroom ceiling or could I just lay insulated duct right on top of it with no problems?  Is the insulated flexible duct really the way to go or would rigid uninsulated duct really be best?


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## buffalo

A straight peice of flexible duct , compared to a rigid duct the same length , has 5x the restriction. At the same time a rigid uninsulated duct could condensate. I would be more worried about condensation so long as the fan is adequately venting the room with the flexable. I guess insulated rigid would be the best , but maybe that's just overkill? 

 I'm wondering  , is that insulated duct you posted going to fit through the existing holes in the lumber? Also , I could be wrong but the white flexible duct is what I have seen used for exhaust fans and dryer vents , the flex you posted is what I see for hot air supply ductworks. Thier may or may not be a differance , but I'm thinking thier is.


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## thapranksta

The flexible insulated duct does not fit into the existing holes without forcing it through.  I would have to enlarge the holes in order for it to fit without restrictions.


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## oldognewtrick

Get a couple of metal 4" 90* elbows to go through the existing hole. Attach the flex to them and pull the insulation over them and secure with sheet metal screws.


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## slownsteady

Just letting the duct rest on the drywall ceiling is probably not going to cause any issues. It is a better choice than tying it up with string. If you want to support it off the drywall, you need to find a wide base to rest the duct on. And you want to avoid the dips and sags between the supports. You could staple up something like chicken wire or some kind of fabric to act like a hammock for the duct, but by the time you factor in the extra labor and the cost of the materials, you can see why rigid ducts have an advantage.


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## thapranksta

In terms of rigid duct, is PVC as good as metal?


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## buffalo

Bassett hangers , they are telescopic and you nail them into the joists.

In all honesty  , your over killing it. Get more 4" round white flex and rerun it.


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## slownsteady

buffalo said:


> Bassett hangers , they are telescopic and you nail them into the joists.
> 
> In all honesty  , your over killing it. Get more 4" round white flex and rerun it.



I'd rather use string than pay $30/per for a support that won't solve anything.
But after all this, Buffalo makes a point: this isn't a dryer vent that's subject to lint collection, and a 4 inch duct should supply enough air flow, even if it's not perfectly straight.


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## buffalo

slownsteady said:


> I'd rather use string than pay $30/per for a support that won't solve anything.
> But after all this, Buffalo makes a point: this isn't a dryer vent that's subject to lint collection, and a 4 inch duct should supply enough air flow, even if it's not perfectly straight.



Yea , you can buy those hangers from an hvac shop cheap. It was just a link to show what's out there , not the best price. I would never buy anything hvac from a big box store , 4x the price.


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## thapranksta

Guys, 

Ultimately I went with flexible foil.  I know it's not the best option but it avoids the mildew issues I experienced with the plastic.   Right now I have no hangers installed and there is a small sag.  I sealed off the joints with heavy duty duct tape.  No steel wool has been installed around where the duct exits yet but that will be the next step.


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## thapranksta

No steel wool




Steel Wool




Steel Wool w/ caulk




Connection to fan with 3'' to 4'' adapter and duct tape





Figured subfloor is a no traffic area so aluminum wouldn't be much of a liability


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## thapranksta

4'' flexible aluminum running under subfloor


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## slownsteady

You must have used a whole tube of caulk : No worries, looks like it'll hold. I would want to check that duct tape every so often though.


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## thapranksta

Thanks for the subtle suggestion.  I never knew 'duct' tape isn't recommended for ducts.  I wish I had known sooner.  &#128542;


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## thapranksta

Updates:  switched out duct tape for foil tape


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## thapranksta

I haven't updated in a while but I thought I'd mention that I am going to go with 2x4 and 2x6 blocking along the walls.  The boxes seem like overkill.

EDIT: Part of the reason I hadn't finished yet is I am trying to see if the mildew smell will subside first but it seems pretty stubborn.


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## nealtw

Do a closer inspection for mold growth somewhere .


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## slownsteady

After all this, it would be a bummer if it wasn't coming from the duct at all......but the possibility has to be considered.


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## oldognewtrick

Looking back at your first set of pics, the brick wall where the vent exits, are there any voids in the mortar above or around the exhaust vent?


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## thapranksta

It appears to be no voids in the mortar around the exhaust vent from an outside view. Inside I can't see anymore since it is stuffed with steel wool and caulked.

Yes, the duct may not have been the source but mildew was definitely growing on the duct and the duct had a big hole in it.  So the duct had to go anyway you look at it.  

Now you guys got me thinking though.  Seems like there would be two key areas to examine - right where the hole was in the vent and where the bathroom fan connects to it.


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## oldognewtrick

The wall pic showed what looked like voids higher on the wall, could be shadows. Voids will allow water to enter.


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## thapranksta

Haven't had the chance to figure out the mildew smell still but I am blocking up the other corner I removed to replace the subfloor.  I plan to cut some insulation afterward, apply subfloor caulk for squeaks and secure down subfloor with screws.


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## thapranksta

And pics...the remaining corner has a screw protruding below it which I will have to cut or break off before I can install the last block.


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## nealtw

Your blocking looks mor perfect than needed, actually it looks great. You are just trying to replicate the strength of the T&G so that any flexing in one peice will tranfer to the other sheet so shorter blocks screwed to both sheets will do the job. I'm not knocking your job, it looks great.


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## Snoonyb

No matter which ducting material you use, you will have condensation, because you are exhausting moisture laden air, and the way to mitigate that, is to continue the vent operation until the air in the bathroom balances with that of the dwelling.

The volumetric inefficiency of the wire reinforces flexible venting material, while easier to install, inherently lends itself to condensation.

In over 35yrs. of practice, I've never used flexible ducting in the wall, under the floor or in the attic.

And a point of clarification, there are different grades of duct tape. I use that which has the greatest thread count and have returned after 25yrs. for another kitchen remodel and had to cut the tape to remove it.

Quality begets quality.


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## thapranksta

What type of rigid ducting do you primarily use Snoonyb?  Metal or PVC?

I have attached a picture of a dry fitting for the subfloor. My concern now has been whether or not expansion and contraction will become an issue if I don't have enough space between the pieces.

The small strip is because of a mistake I made in measuring.  I ended up replacing the 2x4 blocking in that area with 2x6 so I could attach both pieces tothe existing subfloor.


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## Snoonyb

thapranksta said:


> What type of rigid ducting do you primarily use Snoonyb?  Metal or PVC?
> 
> I have attached a picture of a dry fitting for the subfloor. My concern now has been whether or not expansion and contraction will become an issue if I don't have enough space between the pieces.
> 
> The small strip is because of a mistake I made in measuring.  I ended up replacing the 2x4 blocking in that area with 2x6 so I could attach both pieces tothe existing subfloor.



I use metal, including any special fittings which need to be fabricated.

Since your flooring material is T&G, there should not be any gaps because of the composition of the material, which does not lend itself to expansion or contraction.

The only thing I would add to the blocking you have accomplished, is to pilot a screw in the edge of the 2x blocking too preclude any potential twisting, block to block or block to joist.


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## thapranksta

Pilot a screw in the edge?


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## Snoonyb

thapranksta said:


> Pilot a screw in the edge?



The edge of the 2x blocking is 1-1/2" and when you drive a #9x4" screw to attach the end to the TJI or another block, depending upon the species of lumber the blocking is, it can split.

Thats why I use a pilot bit and pre-pilot.


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## frodo

http://www.bing.com/images/search?q=4%27%27+snap+lock+duct&view=detailv2&&id=383DCFF026A55F0F64115E8062EE0B0F7EAB0200&selectedIndex=7&ccid=%2fkx4xnxH&simid=607986508808257767&thid=OIP.Mfe4c78c67c473e97cb564593852e5429o0

http://www.bing.com/images/search?q=metal+duct+tape&view=detailv2&&id=37CA3F0981E2A688BC7895A77729A973799C2928&selectedIndex=7&ccid=BJjEm5h2&simid=608018549255570892&thid=OIP.M0498c49b98768a417b22871a6446419ao0


http://www.bing.com/images/search?q=duct+crimper+tool&view=detailv2&&id=ABC4C8B272250ABC39311BBC6831A98ED41BE4A1&selectedIndex=10&ccid=4oygT29L&simid=608039994025512691&thid=OIP.Me28ca04f6f4b629b0ce62711e768dbc1o0


http://www.bing.com/images/search?q=duct+insulation+wrap&view=detailv2&&id=2DEA4C91B0DBB85957DBBE879B5781018B0531DE&selectedIndex=0&ccid=EL1X7Mtf&simid=608006871246505438&thid=OIP.M10bd57eccb5fc1c95e2dd9bcdedd0af8H0


the above items,  snap lock duct 
                        hvac metal tape
                      crimpers
                     insulation
use these items,  to run that exhaust vent,  what you curently have is not ment for what it is being used for

that is a dryer vent,,


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## thapranksta

It's been over a year and half since I posted on this thread.  This project still isn't completely done.  I know that's bad but hey, what can I say....life happens.

I thought I'd give some updates however. The flexible foil venting I installed was still intact when I revisited the subfloor but I decided I only wanted to do this once and do it the right way even if it was a little pricey.  So I actually followed some of the possible "overkill" advice and the last post from frodo above.  I already started installing rigid duct.  And so far it has gone ok.

But there is a very important thing that I encountered when I started running this duct and this was just basic logic about the air flow.  With rigid duct, the way you run the duct does make a difference.  By this I mean, the crimped end of each pipe segment should be in the same direction as the air flow because otherwise, there is a higher chance of leakage at the joints.  I figured this out a little under halfway through after I had already run the pipe ends in the wrong direction and so I had to cut off a crimped edge I made manually on the small piece of pipe that exits my house and basically start over.

Will add pictures later.


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## nealtw

thapranksta said:


> It's been over a year and half since I posted on this thread.  This project still isn't completely done.  I know that's bad but hey, what can I say....life happens.
> 
> I thought I'd give some updates however. The flexible foil venting I installed was still intact when I revisited the subfloor but I decided I only wanted to do this once and do it the right way even if it was a little pricey.  So I actually followed some of the possible "overkill" advice and the last post from frodo above.  I already started installing rigid duct.  And so far it has gone ok.
> 
> But there is a very important thing that I encountered when I started running this duct and this was just basic logic about the air flow.  With rigid duct, the way you run the duct does make a different.  By this I mean, the crimped end of each pipe segment should be in the same direction as the air flow because otherwise, there is a higher chance of leakage at the joints.  I figured this out a little under halfway through after I had already run the pipe ends in the wrong direction and so I had to cut off a crimped edge I made manually on the small piece of pipe that exits my house and basically start over.
> 
> Will add pictures later.



Oops, it not the kind of thing the pros will think of saying, good catch.


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## thapranksta

I am still deciding on whether or not I need to add insulation.  Also it is a long run and there will be at least 8 elbows (which seems like a LOT) using the existing route the plastic flex followed through the i-joist webbing.  I am using sheet metal screws and aluminum tape to secure each joint.


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## joecaption

That's way too many elbows!
There's going to be almost no air flow.
Figure out how to run it a different way to make it a shorter run.


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## thapranksta

I had a feeling that might be the case.  I will take some pictures tomorrow hopefully to show what I have so far before I go the route of ripping a lot of stuff out.  If I do try to eliminate the elbows I will have to cut some more holes in the I joist and possibly seal some of the existing holes.  I am aware that there are certain rules to follow as far as size and how far apart the holes can be from each other.  Sigh...


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## nealtw

If you can find the makers tag for the joists, they will supply instructions for hole but they are all similar.
[ame]https://www.youtube.com/watch?v=mndPt8qV5wg[/ame]


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## Snoonyb

Your local building dept. will also provide you with a chart similar to this, that they have adopted as their standard;http://www.ahjengineers.com/wp-cont...lowed-hole-charts-for-Trus-Joist-products.pdf


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## thapranksta

Pictures of current state of things as mentioned before:

Best shot I could get of run I already installed






Where vent exits





a mid point in the run





current end





As mentioned before, it would be 8 elbows with the current plan I have.  The total estimated length of the completed run is ~25 feet.  The longest run is 10'8'' and the shortest would be right where it connects to the bathroom fan box because it is a sharp angle - 2 90 degree elbows put together.  Looks like I've got some more undoing and planning to do.  Hopefully I can re-use a lot of my bad connections thus far instead of going to buy more new duct.  I also hope I don't have to open up more subfloor.


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## nealtw

I didn't go back and read the refresher course. I there no way to go up and out.


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## Snoonyb

Elbows are "adjustable" from 0 to 90, and using them as close to "0" as you can will reduce their limiting effect upon air flow.

You can accomplish this by the appropriate elongating of the holes in the joists, thereby eliminating elbows.


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## thapranksta

OK.  I think I follow.  I have two possible plans right now.  One of them has 6 joints with angles of 45 degrees or less.  The other plan has 5 angles but one would be a 90 degree.

Neither plan really eliminates 90 degree turns altogether because I basically have to turn 180 degrees to reach the fan box opening.  I am just widening the curves. I am not sure if rotating the fan box is feasible but it doesn't seem like something to fiddle around with.

I am leaning toward the first plan with 6 joints of 45 degrees or less and leaving the fan box as is.


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## oldognewtrick

What about the possibility of changing the exit to daylight? Is there a straighter option? Just thinking out loud.....


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## thapranksta

Unfortunately, there isn't a straighter option without ripping up a good bit of subfloor and also cutting out rim board and siding. Also would have to pull up carpet and padding in a bedroom. This would change the exit to the rear of my house (vinyl siding) instead of the side (brick).  Then there is no telling what I will encounter as I have learned so far.


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## oldognewtrick

What about verticle?


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## Snoonyb

Your plan A will decrease the resistance, IE., back pressure, also, if you have the room, use 2, 45's instead of a 90, for the 90 degree change.


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## thapranksta

The bathroom is on the first floor which means I'd have to get it up through the 2nd floor and to the attic to run it vertically.  There is a wall cavity near where the vent fan is housed but if I am thinking about this correctly, a 4'' pipe will not fit in a wall cavity because the max depth is only 3.5'' because of the 2x4 studs.  Sounds like it is some questionable code stuff with that as well.    Edit:  I guess I could always just leave the pipe completely exposed instead of routing through the walls even though that isn't aesthetically pleasing.

I have been implementing Plan A and reduced 4 of the 90 degree joints into two 45 degree joints by taking a more direct path diagonally.  I'm not done yet obviously but near the bath fan box, I plan to make the widest bend I can make within the joist bays to make a 180 degree angle.  That will be four 45 degree joints (to make two wide 90 degree joints) and a couple of short straight lengths. This is how I came up with a total of six 45 degree angles Snoonyb.  I wish I could make a graphic or something to give a better idea of what I mean because I can't take pictures of the entire length.


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## thapranksta

I have the whole pipeline complete and just about finished adding insulation except I realize that I have not overlapped the insulation anywhere.  I just have coverage on all the pipe except the elbow joints that go through holes in the joists.

Do I need to overlap the insulation?  It seems like this would be more of an issue if I was venting through the attic instead of under the 2nd floor of my house but I have no idea how much temperature variance happens there.  This room is not over the garage though which I know is a problematic area.

Please tell me I don't need to start this over again.  *face palm*


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## oldognewtrick

Are you taping the seams?


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## thapranksta

Yep.  I am taping the seams.  Practically every seam has sheet metal screws as well as tape.

I am using two types of insulation - fiberglass and self adhesive.  












Edit: Kinda hard to capture the whole run especially since some of it is hidden by subfloor but a couple more shots.  I have to go back and make sure that seam in the first picture has tape.

A snake through joist





At fan box


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