What kind of insulation here??

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Billbill84

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IMG_1042.PNG IMG_1043.PNG Hey guys. Just wondering what kind of insular should I put up over this vapor barrier plastic? I plan on leaving the area wall open like in the photos so I can keep the sump discharge line warm to the warm basement air as the basement is the hottest place in the winter a grizzly could hibernate lol. Already had the sump line freeze when it was fully finished in this area and had a mess in that wall prior to tearing it all out, so a little insulation behind the PVC wouldn't be a bad idea I don't think. I'm thinking some R30 up to the subfloor past the rimmer and calling it a day as the pipes will benefit from my warm basement temp and I can monitor it throughout winter. Spray foam is out of the question because per code, id have to have that drywall barrier reinstalled and i don't want drywall in this area. Any ideas?
 
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R30 will stick out into the space about 6", so why not pipe wrap insulation or R13 unfaced, or at the most R19 unfaced, which will only protrude about 3"?
 
R30 will stick out into the space about 6", so why not pipe wrap insulation or R13 unfaced, or at the most R19 unfaced, which will only protrude about 3"?
How good is that pipe wrap insulation? Will that work for 1.5" pvc? Also is there a benefit to using unfaced? I would of thought to use faced but I don't really know much about the difference
 
I assume you currently have insulation behind that poly vapour barrier.

You don't have much room if trying to keep insulation behind the pipe, so I would go with something high R value per inch. Of the common insulations, that would be XPS. That would be the heavier, colored styrofoam. Its also more expensive than some other options, but looks like you don't need much.

Edit -- oh you don't want to drywall it. I think you would have to per code. So otherwise, I would suggest rockwool.
 
I agree with Steve. If you are going to leave that area unfinished use fire rated rock wool insulation. Do not use faced insulation. Frozen pipes make a mess but nothing like a fire even if we weren't talking about your family's safety.
 
I haven't read everything here but understanding the system you have would be good start.
The sheet poly here is not considered a VB in the normal way. It is there to capture water that might leak or wick thru the concrete and send it to below the floor to the drain, Keeping the inside of the wall cold with insulation stops the wicking .
Warm mobil 4.png ist air getting to the cold surface will condense and with a little dirt the mold can and will grow.
The sump pump discharge is wrong.
It should go up into the ceiling and out the rim joist on a slope to the outside thru the insulation.
That way when the check valve holds water anything that might freeze drains to the outside and is gone.
The should be freeze flare on the outside in case the drain in the ground freezes up the water can still be discharged.
 
I assume you currently have insulation behind that poly vapour barrier.

You don't have much room if trying to keep insulation behind the pipe, so I would go with something high R value per inch. Of the common insulations, that would be XPS. That would be the heavier, colored styrofoam. Its also more expensive than some other options, but looks like you don't need much.

Edit -- oh you don't want to drywall it. I think you would have to per code. So otherwise, I would suggest rockwool.
No from what I can see they just put up that plastic over the foundation wall then insulation over that. It's a 1400sqft basement I'm just wondering now after tearing that part of wall out (discharge line fracture) if they even finished the basement properly back in 2003 when they said they completed it. It's nice and well insulated, cold in summer, hot in winter.
 

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In northern climates, vapor barrier goes in the "warm in winter" side of the insulation. Must not be a VB, as Neal suggested.
 
I haven't read everything here but understanding the system you have would be good start.
The sheet poly here is not considered a VB in the normal way. It is there to capture water that might leak or wick thru the concrete and send it to below the floor to the drain, Keeping the inside of the wall cold with insulation stops the wicking .
Warm moView attachment 22880 ist air getting to the cold surface will condense and with a little dirt the mold can and will grow.
The sump pump discharge is wrong.
It should go up into the ceiling and out the rim joist on a slope to the outside thru the insulation.
That way when the check valve holds water anything that might freeze drains to the outside and is gone.
The should be freeze flare on the outside in case the drain in the ground freezes up the water can still be discharged.
From what I can tell my system is the foundation covered with that plastic then a yellow colored insulation with white plastic faced over the insulation itself in the walls (that's what I ripped out of the area pictured anyway). I plan on redoing that discharge like you say but did it like this to keep most of the pipe in the warm air and didn't want to pop another hole in my wall. Last few nights been cold and I went in there and felt the discharge line that runs along the rim and it's been warm.
 
The sheet poly here is not considered a VB in the normal way. It is there to capture water that might leak or wick thru the concrete and send it to below the floor to the drain,
So wait a minute, not to be off topic here but maybe the mysterious white pvc pipe that goes to my sump pit is just that, the inside floor weep drain? I even posted about it before. I've never known what its purpose was because I've never seen anything come out of it. Maybe it's the end of the inside wall perimeter drain
 

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In northern climates, vapor barrier goes in the "warm in winter" side of the insulation. Must not be a VB, as Neal suggested.
I did not suggest that that poly was a vapour barrier, it is a drain plane only. if it is done here a vapour barrier is still installed on the warm side of the wall.
 
New guy jumping in without reading all posts.

The mystery pipe from your sump pit might be a radon collector.
It can be passive, just venting by chimney action, or it can go to a pump outside or in the attic.
 
New guy jumping in without reading all posts.

The mystery pipe from your sump pit might be a radon collector.
It can be passive, just venting by chimney action, or it can go to a pump outside or in the attic.
Hi there. Are you saying it could be collecting any radon from the sump pit and venting out somewhere else?
 
Hi Bill,

Radon collection systems often have a pipe that penetrates the basement slab, and draws radon gas from the ground that collects in the gravel layer down there.

But another method is to put a collection pipe into the sump pit, because the sump pit sits under the slab and has access to trapped radon that gets in from around the perimeter drain pipe opening, or up through a gravel covered bottom.
The pit then has a cover placed over it.

The collection pipe then normally runs up and out the roof, not combined with any plumbing venting.
Or it can leave out the side of the house and go up to the roof height.
Some systems have a fan that pulls the air forcefully, others just let the radon rise by a natural chimney effect.

It might not be a radon pipe, but I just mentioned it since you were otherwise stumped.
 
Hi Bill,

Radon collection systems often have a pipe that penetrates the basement slab, and draws radon gas from the ground that collects in the gravel layer down there.

But another method is to put a collection pipe into the sump pit, because the sump pit sits under the slab and has access to trapped radon that gets in from around the perimeter drain pipe opening, or up through a gravel covered bottom.
The pit then has a cover placed over it.

The collection pipe then normally runs up and out the roof, not combined with any plumbing venting.
Or it can leave out the side of the house and go up to the roof height.
Some systems have a fan that pulls the air forcefully, others just let the radon rise by a natural chimney effect.

It might not be a radon pipe, but I just mentioned it since you were otherwise stumped.
Good possibility. Thanks for the insight. I'm going to look into this further.
 

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