# Air sealing near dryer vent?



## Windows on Wash (Aug 30, 2011)

Tape all the seams with proper foil tape. 

Spray for for seal at the wall where it goes through. I would put a bit of roxul in the hole and spray over it so it does expand to outside. 

I would spray foam where it touches the concrete or is adjacent, and roxul the rest.


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## Red Squirrel (Jun 29, 2009)

So it's ok for the spray foam to be in contact with it? Since that is an awkward area to tape vapour barrier (for the inside part) I might just spray foam the whole thing then just vapour barrier up to the next 2x4. Then just tape the face of the 2x4 so tape is on the insulation too, that should provide a half decent seal. Going above and beyond ensuring everything is sealed as tight as possible, my upstairs is done terribly and I freeze in winter because of it so may as well do the basement as best as I can, so eventually I might redo the upstairs. That would involve taking all the drywall out, so a pretty messy job. 

Basically I have a few of these "odd" areas that I am reserving for after I'm done foaming the rim joists, whatever I have left over in the canisters will go to these areas so I can keep using it until I run out. You only get one go at it so may as well make the most of it. 

I might also move some of that pipe over a bit to make it easier to work around. Once I open up that side wall it will make it easier to route it better. That whole wall is kinda awkwardly built.


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## Red Squirrel (Jun 29, 2009)

Did some cleanup with that wall to make it easier to tie in vapour barrier from one side to the next if I go that route, ended up being easier to just take that whole section of drywall out. It has wallpaper anyway, probably easier to redrywall than to take wallpaper off.  






So here's what I'm thinking, I'm not comfortable having foam touching that pipe so I'll stick to a standard batt insulation + vapour barrier now that I made the wall easier to work with, but regular plastic would melt (or would it?), so for the section in red, I need to use a different kind of material that is heat/fire resistant.


(pic is a somewhat edited to take out the partition wall to make it easier to visualize)

Is there a product I can use as a vapour barrier for the red section, that won't melt from the dryer pipe? I'm thinking a section of sheet metal or some kind of heavy duty tin foil, but not really sure where to buy that. The reason I'm covering such a large area is that it will just be easier to tie in the regular plastic for the rest of the basement as there is something solid to staple/tape to. I only really need it near the actual pipe and where it will have to seal with it. I will just use duct tape (like for actual ducts) to tie to the actual pipe. The way this dryer vent exits is awkward so it makes it a bit harder to work with.


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## Bud9051 (Nov 11, 2015)

Thread too long to read the entire post, but I saw "vapor barrier" and think it implied it was going over the basement wall. Apology for not reading, really busy. If you are not using a vapor barrier, skip this post. If you are, why?

Bud


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## Red Squirrel (Jun 29, 2009)

It's to air seal, otherwise you get drafts etc. Insulation alone will not stop drafts. The vapour barrier goes on the warm side (inside).


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## mikegp (Jul 17, 2011)

Are you afraid of what will happen if a lint fire ignites or are you under the impression that dryer vents get very hot? With such a short straight run, you should be able to keep that vent clear. They also make fire rated spray foam. Get some of that and be done with it.


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## Red Squirrel (Jun 29, 2009)

Mostly because it will get hot and melt the plastic or cause tape to unstick, but also if there is a lint fire it would be bad too. Though I don't think lint is too much of an issue for me from when I inspected it, there was only a fine dust.

I was thinking about that fire foam too, might do that. Just need to build out a frame around it so I can foam the frame then tie the plastic to the frame, so it's a continuous seal. Probably going to end up doing that. The laundry room in general is going to be tricky as I also need to redo the electrical panel so I can do a proper insulation job (need to bring it out so I can insulate behind) and also need to redo plumbing as I went and did it in the wall not thinking that I need to insulate it. So that whole room will probably go as another project later on.


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## Red Squirrel (Jun 29, 2009)

I was looking at it further as I was finalizing the vapour barrier on the left side of the wall, and decided I'm just going to move where it exits the house and put it under the other pipe that exits (that one is for a fan). Going to make things so much easier as I can have the pipe come straight out instead of that awkward angle. I have spare bricks, so I can fix the hole that will be left by removing the old one. I'm thinking I could use a collar for a wood stove and tie vapour barrier to that, or maybe just a piece of sheet metal and aluminium tape as the vapour barrier for around the pipe. I think by the time the heat spreads throughout the sheet metal it will be cool enough that it won't melt the vapour barrier that it meets with. Think that should work and be safe?


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## Bud9051 (Nov 11, 2015)

Vapor barriers go to the inside (if used at all) when the wall assembly can dry to the outside. Your drywall can be your air barrier. I'm just suggesting you allow the wall to dry to the inside, the amount of moisture would be minimal and it avoids possible accumulation in the area behind the wall.

Bud


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## BIG Johnson (Apr 9, 2017)

Red Squirrel said:


> I was looking at it further as I was finalizing the vapour barrier on the left side of the wall, and decided I'm just going to move where it exits the house and put it under the other pipe that exits (that one is for a fan). Going to make things so much easier as I can have the pipe come straight out instead of that awkward angle. I have spare bricks, so I can fix the hole that will be left by removing the old one. I'm thinking I could use a collar for a wood stove and tie vapour barrier to that, or maybe just a piece of sheet metal and aluminium tape as the vapour barrier for around the pipe. I think by the time the heat spreads throughout the sheet metal it will be cool enough that it won't melt the vapour barrier that it meets with. Think that should work and be safe?


That dwg is how you do a DV gas fireplace, never seen it for a clothes dryer. I don't think they get that hot.


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