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Discussion Starter #1
Hi everyone! I have a question about my basement walls. Do you put plastic against the block walls before studding out or not. I put some on one wall and it caused water to form on the outside of the plastic, which I think would get inside my studded wall after it is finished. I took the plastic off and the wall is dry now. So I am confused I have 2 coats of Drylock on all block walls. Do I even need plastic, cause it seems it is going to cause more trouble, Thanks!
 

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Concrete & Masonry
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I think it really depends on your region, as vapor barrier technology changes fairly often nowadays. In my area, you ABSOLUTELY cannot use a vapor barrier on below grade basement walls. It is required on above grade wood walls in a basement on a partial or full exposure basement though. BTW, don't put too much trust into the Drylok, for if you had foundation leakage problems before, they will surface again even with the Drylok.
 

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listen to him :yes: below-grade negative-side damp-proofing appears to have no rhyme or reason for success,,, if moisture appear'd between the vapor barrier & the wall, that silver bullet obviously didn't work,,, sounds as if the 1 layers of dry-lock'll be the final finish to me.
 

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Agreed, plastic is rarely a good idea in any part of a wall assembly.

Furthermore, if you insulate your stud walls the paper face of the insulation is a vapor barrier. With it and plastic in the same wall you're creating a sandwich, which is just not a good idea.

If your walls are allowing moisture to permeate, you really need to give some thought to fixing that problem before considering a basement finish.
 

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Discussion Starter #5
Thanks, I'm leaning that the plastic is just itself creating condensation, the basement is very dry, drain tiled around the footers well and waterproofed on the outside during construction and all slopes and gutters are running away from the house as well as 2 coats of drylok on inside. It has 9' ceiling height which I love, seems as dry as basements come, this was confusing to me because the water was forming on the plastic, not the wall, cause when I removed the plastic the wall was dry behind it, sort of like the plastic was making the wall sweat if that makes any sense.
 

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The cooler temps of the wall may have caused condensation of the air's moisture on the plastic, just like a cold soda can has condensation on it.
 

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Unless you live in a very cold area, do not use plastic. Kraft paper is a Class 2 vapor retarder. Some moisture can pass through it as this article brings out: http://www.buildingscience.com/docu...rol-for-new-residential-buildings?full_view=1

Notice the different wall assemblies and different locations. The beginning explains where the water vapor comes from. Also there are the different classes of vapor retarders, and there types. Figures towards the end show various basement systems with different wall construction. Be safe, G
 

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Wire Chewer
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I've been told you have to put plastic and i've seen unfinished basements with plastic, but yeah not sure how the moisture is kept out from between the brick and plastic. Indoor weeping tiles? LOL

Just don't put studs/insulation right against the cement or it may cause mold over time, depends how damp the basement is. I've been toying with the idea of studding my crawlspace but these are all things I need to take into consideration.
 

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Discussion Starter #11
Hi Red Squirrel, that was what made this so confusing is I was told that as well , anyway good thing I caught it before I put the walls in. Go figure.
 

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Discussion Starter #12
Me again, I'm still studying this out and I think I will stud out with treated wood and use densboard(paperless) drywall and just stain and seal the concrete floors and use large area rugs. Seems simpler in basement. Does anyone know if they make a mold/mildew inhibitor/blocker that I could spray on the block and studs before I densboard that way I would'nt have to worry about any mildew getting inside the walls?
 

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'waterproofing' is a system which includes walls, footers, toe drains, sump, & vapor barrier under the floor,,, several top-notch bldrs even have a rubberized asphalt membrane applied to the walls protected by pvc dimpleboard,,, you refer to what's commonly known as 'dampproofing',,, as i recall, rolling on a 3mil thickness of apron store asphalt emulsion meets that spec,,, as 'mite notes, building to the MINIMUM standard's easy & often leads to expensive repairs later.

your moisture test proves there's water,,, wet runs to dry as surely as cold runs to heat - hi school physics ! ! ! sometimes we're just not supposed to live below the waterline.
 
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