Unfaced insulation
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Unfaced insulation
How difficult is it to find unfaced r-13 insulation? I'm insulating my basement walls with 2" rigid foam then stud walls, then unfaced fiberglas. Home Depot only carries kraft-faces r-13. Anyone???
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What's the point of putting poly over the studs, if I'm using unfaced fiberglass insulation? The whole point of the styrofoam boards is to raise the surface temperature of the foundation walls so moisture doesn't condense on it, but at the same time allowing moist air to pass through the styro, thus not becoming trapped and risking mold/mildew problems. The poly would prevent the moisture from evaporating.
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So the warm air with all the moisture in it cant get to that cool cement wall from the room now and in summer. We hang a V/B on the cement wall then the studs with insulation then a poly then the drywall. Dont forget the bottom plate has to be P/T. Have did it this way for over 30 years been back on some and no mold
ED

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The cement wall is not cold; it is covered with 2 inches of styrofoam, so moist air won't condense on it. If you hang poly over the cement wall, how does any moisture coming from the ground outside evaporate since it can't get through the poly? It won't go back out the way it came. It will just sit there, forming mold and mildew between the cement and the poly.
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If you have a small polystyrene ice box put some ice and water in it let it sit on the cement floor You will find that the floor will get wet. Also the walls are cool in the summer.and with just the air in the room they will sweat. Its not from out side in it from inside out. Have also built some earthcontact home they have all been dry and no mold . Been there done that ED

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If you GLUED the cooler to the floor, you would not get any moisture on the floor. The moisture comes from the air between the bottom of the cooler and the floor condensing onto the floor, which has had its temperature lowered by the cooler. Read this article: http://www.buildingscience.com/resou...on_systems.pdf
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Sorry try it the floor will get wet. In the summer that wall is cooler than the air so you get water on it. Like I said have been building homes for over 30 years and have did it this way with no mole .
we do use 2" or 3"polystyrene on the walls of the crawl space and seal it but thats the only time or place. Good luck
ED
we do use 2" or 3"polystyrene on the walls of the crawl space and seal it but thats the only time or place. Good luck
